Rational design of mixed nanomicelle eye drops with structural integrity investigation

A review on revolutionizing ophthalmic therapy: Unveiling the potential of chitosan, hyaluronic acid, cellulose, cyclodextrin, and poloxamer in eye disease treatments

Ocular disorders, encompassing both common ailments like dry eye syndrome and more severe situations for instance age-related macular degeneration, present significant challenges to effective treatment due to the intricate architecture and physiological barriers of the eye. Polysaccharides are emerging as potential solutions for drug delivery to the eyes due to their compatibility with living organisms, natural biodegradability, and adhesive properties. In this review, we explore not only the recent advancements in polysaccharide-based technologies and their transformative potential in treating ocular illnesses, offering renewed optimism for both patients and professionals but also anatomy of the eye and the significant obstacles hindering drug transportation, followed by an investigation into various drug administration methods and their ability to overcome ocular-specific challenges. Our focus lies on biological adhesive polymers, including chitosan, hyaluronic acid, cellulose, cyclodextrin, and poloxamer, known for their adhesive characteristics enhancing drug retention on ocular surfaces and increasing bioavailability. A detailed analysis of material designs used in ophthalmic formulations, such as gels, lenses, eye drops, nanofibers, microneedles, microspheres, and nanoparticles, their advantages and limitations, the potential of formulations in improving therapeutic outcomes for various eye conditions. Moreover, we underscore the discovery of novel polysaccharides and their potential uses in ocular drug delivery.

Current perspectives and trend of computer-aided drug design: a review and bibliometric analysis

AIM

Computer-aided drug design (CADD) is a drug design technique for computing ligand-receptor interactions and is involved in various stages of drug development. To better grasp the frontiers and hotspots of CADD, we conducted a review analysis through bibliometrics.

METHODS

A systematic review of studies published between 2000 and 20 July 2023 was conducted following the PRISMA guidelines. Literature on CADD was selected from the Web of Science Core Collection. General information, publications, output trends, countries/regions, institutions, journals, keywords, and influential authors were visually analyzed using software such as Excel, VOSviewer, RStudio, and CiteSpace.

RESULTS

A total of 2031 publications were included. These publications primarily originated from 99 countries or regions led by the U.S. and China. Among the contributors, MacKerell AD had the highest number of articles and the greatest influence. The Journal of Medicinal Chemistry was the most cited journal, whereas the Journal of Chemical Information and Modeling had the highest number of publications.

CONCLUSIONS

Influential authors in the field were identified. Current research shows active collaboration between countries, institutions, and companies. CADD technologies such as homology modeling, pharmacophore modeling, quantitative conformational relationships, molecular docking, molecular dynamics simulation, binding free energy prediction, and high-throughput virtual screening can effectively improve the efficiency of new drug discovery. Artificial intelligence-assisted drug design and screening based on CADD represent key topics that will influence future development. Furthermore, this paper will be helpful in better understanding the frontiers and hotspots of CADD.

Targeted delivery of MerTK protein via cell membrane engineered nanoparticle enhances efferocytosis and attenuates atherosclerosis in diabetic ApoE-/- Mice

BACKGROUND

Clearance of apoptotic cells by efferocytosis is crucial for prevention of atherosclerosis progress, and impaired efferocytosis contributes to the aggravated atherosclerosis.

RESULTS

In this study, we found that diabetic ApoE-/- mice showed aggravated atherosclerosis as hyperglycemia damaged the efferocytosis capacity at least partially due to decreased expression of Mer tyrosine kinase (MerTK) on macrophages. To locally restore MerTK in the macrophages in the plaque, hybrid membrane nanovesicles (HMNVs) were thus developed. Briefly, cell membrane from MerTK overexpressing RAW264.7 cell and transferrin receptor (TfR) overexpressing HEK293T cell were mixed with DOPE polymers to produce nanovesicles designated as HMNVs. HMNVs could fuse with the recipient cell membrane and thus increased MerTK in diabetic macrophages, which in turn restored the efferocytosis capacity. Upon intravenous administration into diabetic ApoE-/- mice, superparamagnetic iron oxide nanoparticles (SMN) decorated HMNVs accumulated at the aorta site significantly under magnetic navigation, where the recipient macrophages cleared the apoptotic cells efficiently and thus decreased the inflammation.

CONCLUSIONS

 Our study indicates that MerTK decrease in macrophages contributes to the aggravated atherosclerosis in diabetic ApoE-/- mice and regional restoration of MerTK in macrophages of the plaque via HMNVs could be a promising therapeutic approach.

Nanomicellar eye drops: a review of recent advances

INTRODUCTION

Research on nanotechnology in medicine has also involved the ocular field and nanomicelles are among the applications developed. This approach is used to increase both the water solubility of hydrophobic drugs and their penetration/permeation within/through the ocular tissues since nanomicelles are able to encapsulate insoluble drug into their core and their small size allows them to penetrate and/or diffuse through the aqueous pores of ocular tissues.

AREAS COVERED

The present review reports the most significant and recent literature on the use of nanomicelles, made up of both surfactants and amphiphilic polymers, to overcome limitations imposed by the physiology of the eye in achieving a high bioavailability of drugs intended for the therapeutic areas of greatest commercial interest: dry eye, inflammation, and glaucoma.

EXPERT OPINION

The results of the numerous studies in this field are encouraging and demonstrate that nanomicelles may be the answer to some of the challenges of ocular therapy. In the future, new molecules self-assembling into micelles will be able to meet the regulatory requirements for marketing authorization for their use in ophthalmic formulations.

Challenges and strategies for ocular posterior diseases therapy via non-invasive advanced drug delivery

Posterior segment diseases, such as age-related macular degeneration (AMD) and diabetic retinopathy (DR) are vital factor that seriously threatens human vision health and quality of life, the treatment of which poses a great challenge to ophthalmologists and ophthalmic scientists. In particular, ocular posterior drug delivery in a non-invasive manner is highly desired but still faces many difficulties such as rapid drug clearance, limited permeability and low drug accumulation at the target site. At present, many novel non-invasive topical ocular drug delivery systems are under development aiming to improve drug delivery efficiency and biocompatibility for better therapy of posterior segment oculopathy. The purpose of this review is to present the challenges in the noninvasive treatment of posterior segment diseases, and to propose strategies to tackle these bottlenecks. First of all, barriers to ocular administration were introduced based on ocular physiological structure and behavior, including analysis and discussion on the influence of ocular structures on noninvasive posterior segment delivery. Thereafter, various routes of posterior drug delivery, both invasive and noninvasive, were illustrated, along with the respective anatomical obstacles that need to be overcome. The widespread and risky application of invasive drug delivery, and the need to develop non-invasive local drug delivery with alternative to injectable therapy were described. Absorption routes through topical administration and strategies to enhance ocular posterior drug delivery were then discussed. As a follow-up, an up-to-date research advances in non-invasive delivery systems for the therapy of ocular fundus lesions were presented, including different nanocarriers, contact lenses, and several other carriers. In conclusion, it seems feasible and promising to treat posterior oculopathy via non-invasive local preparations or in combination with appropriate devices.

In vitro and in vivo assessment of structural integrity for HPCD complex@Liposome nanocomposites from ocular surface to the posterior segment of the eye

Investigating the structural integrity of carriers in transit from ocular surface to ocular posterior segment is essential for an efficient topical drug delivery system. In this study, dual-carrier hydroxypropyl-β-cyclodextrin complex@Liposome (HPCD@Lip) nanocomposites were developed for the efficient delivery of dexamethasone. Förster Resonance Energy Transfer with near-infrared I fluorescent dyes and in vivo imaging system were used to investigate the structural integrity of HPCD@Lip nanocomposites after crossing Human conjunctival epithelial cells (HConEpiC) monolayer and in ocular tissues. The structural integrity of inner HPCD complexes was monitored for the first time. The results suggested that 23.1 ± 6.4 % of nanocomposites and 41.2 ± 4.3 % of HPCD complexes could cross HConEpiC monolayer with an intact structure at 1 h. 15.3 ± 8.4 % of intact nanocomposites could reach at least sclera and 22.9 ± 1.2 % of intact HPCD complexes could reach choroid-retina after 60 min in vivo, which showed that the dual-carrier drug delivery system could successfully deliver intact cyclodextrin complexes to ocular posterior segment. In conclusion, in vivo assessment of structural integrity of nanocarriers is greatly significant for guiding the rational design, higher drug delivery efficiency and clinical transformation for topical drug delivery system to the posterior segment of the eye.

Carbohydrate polymer-based bioadhesive formulations and their potentials for the treatment of ocular diseases: A review

Eyes are directly exposed to the outer environment and susceptible to infections, leading to various ocular disorders. Local medication is preferred to treat eye diseases due to its convenience and compliance. However, the rapid clearance of the local formulations highly limits the therapeutic efficacy. In the past decades, several carbohydrate bioadhesive polymers (CBPs), such as chitosan and hyaluronic acid, have been used in ophthalmology for sustained ocular drug delivery. These CBP-based delivery systems have improved the treatment of ocular diseases to a large extent but also caused some undesired effects. Herein, we aim to summarize the applications of some typical CBPs (including chitosan, hyaluronic acid, cellulose, cyclodextrin, alginate and pectin) in treating ocular diseases from the general view of ocular physiology, pathophysiology and drug delivery, and to provide a comprehensive understanding of the design of the CBP-based formulations for ocular use. The patents and clinical trials of CBPs for ocular management are also discussed. In addition, a discussion on the concerns of CBPs in clinical use and the possible solutions is presented.

Recent Progress of Solid Lipid Nanoparticles and Nanostructured Lipid Carriers as Ocular Drug Delivery Platforms

Sufficient ocular bioavailability is often considered a challenge by the researchers, due to the complex structure of the eye and its protective physiological mechanisms. In addition, the low viscosity of the eye drops and the resulting short ocular residence time further contribute to the observed low drug concentration at the target site. Therefore, various drug delivery platforms are being developed to enhance ocular bioavailability, provide controlled and sustained drug release, reduce the number of applications, and maximize therapy outcomes. Solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) exhibit all these benefits, in addition to being biocompatible, biodegradable, and susceptible to sterilization and scale-up. Furthermore, their successive surface modification contributes to prolonged ocular residence time (by adding cationic compounds), enhanced penetration, and improved performance. The review highlights the salient characteristics of SLNs and NLCs concerning ocular drug delivery, and updates the research progress in this area.

Nano-based eye drop: Topical and noninvasive therapy for ocular diseases

Eye drops are the most accessible therapy for ocular diseases, while inevitably suffering from their lower bioavailability which highly restricts the treatment efficacy. The introduction of nanotechnology has attracted considerable interest as it has advantages over conventional ones such as prolonged ocular surface retention time and enhanced ocular barrier penetrating properties, and achieving higher bioavailability and improved treatment efficacy. This review describes various ocular diseases treated with eye drops as well as the physiological and anatomical ocular barriers faced with through drug administration. It also summarizes the recent advances regarding the utilization of nanotechnology in developing eye drops, and how to optimize the nanocarrier-based ocular drug delivery systems. The prospective future research directions for nano-based eye drops are also discussed here.

Design of an L-Valine-Modified Nanomicelle-Based Drug Delivery System for Overcoming Ocular Surface Barriers

The incidence of ocular surface disease (OSD) is increasing, with a trend towards younger ages. However, it is difficult for drugs to reach the deep layers of the cornea due to ocular surface barriers, and bioavailability is less than 5%. In this study, DSPE-PEG2000 was modified with L-valine (L-Val), and an HS15/DSPE-PEG2000-L-Val nanomicelle delivery system containing baicalin (BC) (BC@HS15/DSPE-PEG2000-L-Val) was constructed using thin-film hydration, with a high encapsulation rate, small particle size and no irritation to the ocular surface. Retention experiments on the ocular surface of rabbits and an in vivo corneal permeation test showed that, compared with the control, nanomicelles not only prolonged retention time but also enhanced the ability to deliver drugs to the deep layers of the cornea. The results of a protein inhibition and protein expression assay showed that nanomicelles could increase uptake in human corneal epithelial cells (HCEC) through energy-dependent endocytosis mediated by clathrin, caveolin and the carrier pathway mediated by PepT1 by inhibiting the overexpression of claudin-1 and ZO-1 and suppressing the expression of PepT1-induced by drug stimulation. These results indicate that BC@HS15/DSPE-PEG2000-L-Val is suitable for drug delivery to the deep layers of the ocular surface, providing a potential approach for the development of ocular drug delivery systems.