Prednisolone retention in integrated liposomes by chemical approach and pharmaceutical approach

Development of hyaluronic acid hydrogel containing prednisolone-encapsulated nonphospholipid liposomes for the treatment of rheumatoid arthritis

Rheumatoid arthritis (RA) requires therapeutic approaches that alleviate symptoms and inhibit the progression of joint damage. Glucocorticoids (GCs) have been a cornerstone of RA treatment, yet their use is often limited by side effects. Recent advancements suggest that liposome-based delivery systems can improve GC biodistribution, minimizing toxicity. This study introduces an innovative tool for RA treatment using prednisone-encapsulated nonphospholipid liposomes (NPLs) in combination with a hyaluronic acid (HA) hydrogel. Our methodology involved incorporating prednisone (PR) with palmitic acid and cholesterol to formulate stable NPLs using a thin-film hydration technique. The synthesized PR-NPLs, characterized by a mean size of 150 nm, demonstrated uniform distribution and higher drug encapsulation in comparison with conventional phospholipid liposomes. In vitro assays revealed that PR-NPL markedly reduced inflammatory responses in macrophages. Additionally, we successfully incorporated PR-NPL into an HA hydrogel, employing a photoinitiated cross-linking process. This novel composite offered modulable PR release, governed by the degree of hydrogel cross-linking. The developed system presents a promising advancement in RA management, especially suited for intraarticular injections. It potentially enables targeted, controlled drug release with a reduced risk of side effects, signifying a significant improvement over existing RA therapies.

Dexamethasone Palmitate Encapsulated in Palmitic Acid Modified Human Serum Albumin Nanoparticles for the Treatment of Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic inflammatory joint condition characterized by symmetric, erosive synovitis leading to cartilage erosion and significant disability. Macrophages, pivotal in disease progression, release pro-inflammatory factors upon activation. We developed a nanoparticle delivery system (DXP-PSA NPs), based on palmitic acid modified human serum albumin (PSA), to deliver dexamethasone palmitate (DXP) directly to sites of inflammation, enhancing treatment effectiveness and minimizing possible side effects. The system actively targets scavenger receptor-A on activated macrophages, achieving selective accumulation at inflamed joints. In vitro effect and preliminary targeting abilities were investigated on LPS-activated RAW264.7 cells. The in vivo efficacy and safety were evaluated and compared side to side with commercially available lipid emulsion Limethason® in an advanced adjuvant-induced arthritis rat model. DXP-PSA NPs offer a novel approach to RA treatment and presents promising prospects for clinical translation.

Quality by Design for Optimizing a Novel Liposomal Jojoba Oil-Based Emulgel to Ameliorate the Anti-Inflammatory Effect of Brucine

One of the recent advancements in research is the application of natural products in developing newly effective formulations that have few drawbacks and that boost therapeutic effects. The goal of the current exploration is to investigate the effect of jojoba oil in augmenting the anti-inflammatory effect of Brucine natural alkaloid. This is first development of a formulation that applies Brucine and jojoba oil int a PEGylated liposomal emulgel proposed for topical application. Initially, various PEGylated Brucine liposomal formulations were fabricated using a thin-film hydration method. (2²) Factorial design was assembled using two factors (egg Phosphatidylcholine and cholesterol concentrations) and three responses (particle size, encapsulation efficiency and in vitro release). The optimized formula was incorporated within jojoba oil emulgel. The PEGylated liposomal emulgel was inspected for its characteristics, in vitro, ex vivo and anti-inflammatory behaviors. Liposomal emulgel showed a pH of 6.63, a spreadability of 48.8 mm and a viscosity of 9310 cP. As much as 40.57% of Brucine was released after 6 h, and drug permeability exhibited a flux of 0.47 µg/cm²·h. Lastly, % of inflammation was lowered to 47.7, which was significant effect compared to other formulations. In conclusion, the anti-inflammatory influence of jojoba oil and Brucine was confirmed, supporting their integration into liposomal emulgel as a potential nanocarrier.

Nanoscale Lipophilic Prodrugs of Dexamethasone with Enhanced Pharmacokinetics

The encapsulation of glucocorticoids, such as dexamethasone, in nanoparticles (NPs) faces two main issues: a low drug loading and the destabilization of the nanoparticle suspension due to drug crystallization. Here, we successfully formulated a prodrug of dexamethasone, dexamethasone palmitate (DXP), into nanoparticles stabilized by the sole presence of distearoyl- sn-glycero-3-phosphoethanolamine- N-[methoxy(poly(ethylene glycol))-2000] (DSPE-PEG₂₀₀₀). Two formulation processes, nanoprecipitation and emulsion-evaporation, allowed the formation of stable nanoparticles. By adjusting the drug/lipid ratio and the DXP concentration, nanoparticles of DXP (DXP-NPs) with a size between 130 and 300 nm can be obtained. Owing to the presence of DSPE-PEG₂₀₀₀, a high drug entrapment efficiency of 98% w/w was reached for both processes, corresponding to a very high equivalent dexamethasone drug loading of around 50% w/w in the absence of crystallization upon storage at 4 °C. The anti-inflammatory activity of DXP-NPs was preserved when incubated with macrophages activated with lipopolysaccharide. Pharmacokinetics parameters were evaluated after intravenous (IV) injection of DXP-NPs to healthy mice. The release of DXM from DXP-NPs in plasma was clearly controlled up to 18 h compared with the free drug, which was rapidly eliminated from plasma after administration. In conclusion, a novel type of nanoparticle combining the advantages of prodrugs and nanoparticles was designed, easy to produce with a high loading efficiency and leading to modified pharmacokinetics and tissue distribution after IV administration.

Dexamethasone palmitate nanoparticles: An efficient treatment for rheumatoid arthritis

Rheumatoid arthritis (RA) is a prevalent autoimmune disease characterized by joint inflammation, bone and cartilage erosion. The use of glucocorticoids in the treatment of RA is hampered by significant side effects induced by their unfavorable pharmacokinetics. Delivering glucocorticoids by means of nanotechnologies is promising but the encapsulation of highly crystalline and poorly water-soluble drugs results in poor loading and low stability. We report here the design of 130 nm nanoparticles made of solely dexamethasone palmitate, stabilized by polyethylene glycol-linked phospholipids displaying a negative zeta potential (-55 mV), high entrapment efficiency and stability over 21 days under storage at 4 °C. X ray diffraction showed no crystallization of the drug. When incubated in serum, nanoparticles released free dexamethasone which explains the in vitro anti-inflammatory effect on LPS-activated RAW 264.7 macrophages. Moreover, we demonstrate in a murine collagen-induced arthritis model the improved therapeutic efficacy of these nanoparticles. Their passive accumulation in arthritic joints leads to disease remission and recovery of the joint structure at a dose of 1 mg/kg dexamethasone, without any adverse effects. Dexamethasone palmitate nanoparticles are promising in the treatment of inflammation in rheumatoid arthritis with a very significant difference occurring at the late stage of inflammation allowing to prevent the progression of the disease.

Nano-engineering of biomedical prednisolone liposomes: evaluation of the cytotoxic effect on human colon carcinoma cell lines

Objectives

Liposomes have attracted the attention of researchers due to their potential to act as drug delivery systems for cancer treatment. The present investigation aimed to develop liposomes loaded with prednisolone base and the evaluation of the antiproliferative effect on human colon carcinoma cell lines.

Methods

Liposomes were elaborated by following a reproducible thin film hydration technique. The physicochemical characterization of liposomes included photon correlation spectroscopy, microscopy analysis, Fourier transform infrared spectroscopy, rheological behaviour and electrophoresis. On the basis of these data and drug loading values, the best formulation was selected. Stability and drug release properties were also tested.

Key findings

Resulting liposomes exhibited optimal physicochemical and stability properties, an excellent haemocompatibility and direct antiproliferative effect on human colon carcinoma T-84 cell lines.

Conclusions

This study shows direct antitumour effect of prednisolone liposomal formulation, which opens the door for liposomal glucocorticoids as novel antitumour agents.

Comparative Effects of Span 20 and Span 40 on Liposomes Release Properties

Liposomes are known as convenient carriers for a broad range of actives. The release rate of actives can be adjusted/controlled by the addition of different surfactants. The aim of this study was to compare the effects of two surfactants, Span 20 and Span 40, on liposomes release properties. In particular, the study shows how the membrane modification affects the mass transfer resistances and liposome size compared with the common liposomes. The aqueous extract of thyme was used as a model substance. It is a valuable source of natural antioxidants – polyphenols. The diffusion of polyphenols from native thyme extract (un-encapsulated) and from different types of liposomes was conducted using Franz diffusion cell. The results were approximated with Fick’s second law and they implied that liposomes modified with Span 20 provided the slowest release of polyphenolic compounds due to the highest value of mass transfer resistance (2.523 × 106s/m).

Antioxidant potential of all-trans retinoic acid (ATRA) and enhanced activity of liposome encapsulated ATRA against inflammation and tumor-directed angiogenesis

The purpose of this study was to investigate whether all-trans retinoic acid (ATRA) has antioxidant property. The study was also focused on its inhibitory effect on the acute and chronic inflammation and tumor-associated capillary formation in terms of angiogenesis in C57BL/6 mice after incorporated in liposome composed of distearoylphosphatidylcholine (DSPC/cholesterol). ATRA possesses a number of important biologic activities including oncostatic, antioxidant and immunostimulatory actions. Our study was designed to evaluate the antioxidant activity of free ATRA by nitric oxide scavenging, superoxide radical scavenging, hydroxyl radical scavenging and lipid peroxide scavenging assays. The ATRA showed significant scavenging activities in all these antioxidant assays comparable to the standard antioxidant. We have also evaluated the activity of encapsulated ATRA against anti-inflammatory activity in C57BL/6 mice. The paw oedema inhibition was found in carrageenan model as 55.56% and 66.67% for free ATRA and encapsulated ATRA treatment respectively and for formaldehyde model it was found to be 60.87% and 69.57% respectively compared with saline treated control mice. Encapsulated ATRA inhibited the tumor-associated capillary formation in mice induced by highly metastatic B16F10 melanoma cells significantly than the free ATRA did. In this study the inhibition of tumor-directed capillary formation was found to be 56.25% and 62.50% for free ATRA and encapsulated ATRA treatment respectively. In conclusion, ATRA showed a significant antioxidant property in vitro. Free ATRA has anti-inflammatory activity as proved by us in animal model of acute and chronic inflammation and antiangiogenesis activity. Furthermore, its activity was boosted by encapsulation in liposome.

Recent applications of liposomes in ophthalmic drug delivery

Liposomal formulations were significantly explored over the last decade for the ophthalmic drug delivery applications. These formulations are mainly composed of phosphatidylcholine (PC) and other constituents such as cholesterol and lipid-conjugated hydrophilic polymers. Liposomes are biodegradable and biocompatible in nature. Current approaches for topical delivery of liposomes are focused on improving the corneal adhesion and permeation by incorporating various bioadhesive and penetration enhancing polymers. In the case of posterior segment disorders improvement in intravitreal half life and targeted drug delivery to the retina is achieved by liposomes. In this paper we have attempted to summarize the applications of liposomes in the field of ophthalmic drug delivery by citing numerous investigators over the last decade.

Enhanced anti-inflammation of inhaled dexamethasone palmitate using mannosylated liposomes in an endotoxin-induced lung inflammation model

Inhalation of bacterial endotoxin induces pulmonary inflammation by activation of nuclear factor kappaB (NFkappaB), production of cytokines and chemokines, and neutrophil activation. Although glucocorticoids are the drugs of choice, administration of free drugs results in adverse effects as a result of a lack of selectivity for the inflammatory effector cells. Because alveolar macrophages play a key role in the inflammatory response in the lung, selective targeting of glucocorticoids to alveolar macrophages offers efficacious pharmacological intervention with minimal side effects. We have demonstrated previously the selective targeting of mannosylated liposomes to alveolar macrophages via mannose receptor-mediated endocytosis after intratracheal administration. In this study, the anti-inflammatory effects of dexamethasone palmitate incorporated in mannosylated liposomes (DPML) at 0.5 mg/kg via intratracheal administration were investigated in lipopolysaccharide-induced lung inflammation in rats. DPML significantly inhibited tumor necrosis factor alpha, interleukin-1beta, and cytokine-induced neutrophil chemoattractant-1 levels, suppressed neutrophil infiltration and myeloperoxidase activity, and inhibited NFkappaB and p38 mitogen-activated protein kinase activation in the lung. These results prove the value of inhaled mannosylated liposomes as powerful targeting systems for the delivery of anti-inflammatory drugs to alveolar macrophages to improve their efficacy against lung inflammation.

Nanoparticles containing anti-inflammatory agents as chemotherapy adjuvants: optimization and in vitro characterization

The pre-administration of dexamethasone (DEX) has previously been shown to enhance the anti-tumor efficacy of chemotherapeutic agents. The delivery of anti-inflammatory agents specifically to tumors via nanoparticle carriers is expected to promote the effectiveness of chemotherapeutic agents while avoiding systemic toxicities. The process for preparing solid lipid nanoparticles containing anti-inflammatory agents using the nanotemplate engineering method was optimized. Due to the solubilization of DEX in the bulk aqueous phase, its more lipophilic palmitate ester was synthesized and incorporated in nanoparticles that included a pegylating agent, PEG6000 mono-stearate, as part of the formulation. The stealth properties of these nanoparticles were demonstrated to be enhanced compared to latex particles by measuring the adsorption of radioiodinated IgG (185 microg vs. 6.7 microg IgG/mg NP). In addition, the uptake of (14)C-labeled nanoparticles by murine macrophages was shown to decrease from 36.6% to 14.7% of the nanoparticles/mg cell protein as the amount of pegylating agent in the formulation increased from 0 to 4 mg/mL. The high loading values and low burst effect observed for these DEX palmitate-containing nanoparticles in addition to their stealth properties are expected to allow for the delivery of sufficient amounts of DEX to tumors to enhance the uptake of chemotherapeutic agents.

Inhibition of pulmonary metastasis in mice by all-trans retinoic acid incorporated in cationic liposomes

The purpose of this study was to investigate whether all-trans retinoic acid (ATRA), an active metabolite of retinal, incorporated in cationic liposomes composed of 1,2 dioleoyl-3-trimethylammonium propane (DOTAP)/cholesterol could inhibit established metastatic lung tumors by delivery to the pulmonary tumor site after intravenous injection. After intravenous injection in mice, the highest lung accumulation of [(3)H]ATRA was observed by the DOTAP/cholesterol liposomes formulation, while other formulations including [(3)H]ATRA dissolved in serum or [(3)H]ATRA incorporated in distearoyl-l-phosphatidylcholine (DSPC)/cholesterol liposomes produced little accumulation in the lung. In mice used as a model of lung cancer metastasis, ATRA incorporated in DOTAP/cholesterol liposomes, injected intravenously, reduced the number of tumor nodules compared with free ATRA or ATRA incorporated in DSPC/cholesterol liposomes. These results suggest that ATRA incorporated in cationic liposomes would be an effective strategy for differentiation therapy of lung cancer metastasis.

Prolonged blood concentration of prednisolone after intravenous injection of liposomal palmitoyl prednisolone

We compared the pharmacokinetic behavior of drugs after an intravenous administration of prednisolone (PLS), palmitoyl prednisolone (Pal-PLS), and liposomal Pal-PLS in rats. Pal-PLS showed higher lipophilicity and higher binding to plasma protein than PLS, and PLS regeneration in rat blood and liver homogenates. After the intravenous administration of Pal-PLS solution in polyethylene glycol (PEG) 400 to rats, Pal-PLS disappeared from the blood in a two-phase mode and PLS was rapidly regenerated. Pal-PLS showed a significantly higher accumulation than PLS in the liver and lung. The administration of Pal-PLS incorporated into egg yolk phosphatidylcholine (EggPC)/cholesterol (Chol) liposomes enhanced Pal-PLS concentrations in the blood, liver, and lung compared to that of Pal-PLS solution in PEG 400, suggesting the rapid removal of liposomes by the mononuclear phagocytic system. Pal-PLS incorporated into PEGylated liposomes constituted with EggPC/Chol/1% L-alpha-distearoylphosphatidylethanolamine (DSPE)-PEG 2000 and EggPC/Chol/10% DSPE-PEG 2000 decreased the initial distribution of Pal-PLS, and successfully maintained the blood concentrations of Pal-PLS and PLS. Thus, we could change the pharmacokinetics of PLS by introducing the palmitoyl function into the molecule and its liposomal formulation including PEGylation. This is the first study to evaluate liposomal PLS constituted with a lipophilic derivative and PEG lipids.

Induction of apoptosis in A549 human lung cancer cells by all-trans retinoic acid incorporated in DOTAP/cholesterol liposomes

All-trans retinoic acid (ATRA) has been shown to exert anti-cancer activities in a number of types of cancer cells. However, it has been reported that many NSCLC exhibited resistance to ATRA treatment. In the present study, we hypothesized that intracellular delivery of ATRA would overcome the ATRA resistance in A549 cells. Here, we investigated the induction of apoptosis by ATRA incorporated in cationic liposomes composed of DOTAP/cholesterol in A549 human lung cancer cells, which are insensitive (resistant) to the growth inhibitory effects of ATRA. The zeta potentials of DOTAP/cholesterol liposomes and DSPC/cholesterol liposomes were about +50 and -3 mV. In A549 cells, [(3)H]ATRA incorporated in DOTAP liposomes showed increased cellular association compared with [(3)H]ATRA or [(3)H]ATRA incorporated in DSPC/cholesterol liposomes. ATRA incorporated in DOTAP/cholesterol liposomes showed much higher cytotoxic effects and apoptosis-inducing activity compared with ATRA or ATRA incorporated in DSPC/cholesterol liposomes. The enhanced expression of TIG3 mRNA tumor suppressor gene by ATRA incorporation into DOTAP/cholesterol liposomes might partly explain the mechanism of enhanced cytotoxicity and/or apoptosis. These observations provide valuable information to help in the design of differentiation therapy by ATRA in non-small cell lung carcinoma.

PEGylated Liposomes Loading Palmitoyl Prednisolone for Prolonged Blood Concentration of Prednisolone

We investigated the pharmacokinetic behavior of palmitoyl prednisolone (Pal-PLS) and its liposomes with L-alpha-distearoylphosphatidylcholine (DSPC) and cholesterol (Chol) with or without L-alpha-distearoylphosphatidylethanolamine-polyethylene glycol 2000 (DSPE-PEG 2000) after their intravenous administration in rats. Pal-PLS rapidly disappeared from the systemic circulation and prednisolone (PLS) was regenerated after the administration of DSPC/Chol liposomes. PEGylated liposomes including DSPE-PEG 2000, however, successfully maintained high blood concentrations of Pal-PLS and PLS. The blood profiles of drugs after the administration of liposomal Pal-PLS were analyzed according to a two-compartment model. The larger content of DSPE-PEG 2000 in DSPC/Chol liposomes showed a lower first order elimination rate constant from the central compartment (K(el)) and clearance (CL). The area under the concentration-time curve (AUC) of Pal-PLS and PLS in PEGylated liposomes was larger than DSPC/Chol liposomes. The mean resident time (MRT) of Pal-PLS and PLS was also prolonged by PEGylated liposomes. Although DSPC/Chol liposomes showed a high distribution of Pal-PLS in the liver and spleen, PEGylated liposomes significantly decreased the liver distribution of Pal-PLS. The biliary and urinary excretions of drugs for 240 min after drug administration were less than 1% of the administrated dose in any formulations. In conclusion, PEGylated liposomes, including Pal-PLS, are useful for maintain the PLS concentration in the blood after intravenous administration.

Biodistribution characteristics of all-trans retinoic acid incorporated in liposomes and polymeric micelles following intravenous administration

The aim of this study was to investigate the biodistribution characteristics of all-trans retinoic acid (ATRA) incorporated in liposomes and polymeric micelles following intravenous administration. [3H] ATRA were incorporated in distearoylphosphatidylcholine (DSPC)/cholesterol (6:4) liposomes. Two types of block copolymers, poly (ethylene glycol)-b-poly-(aspartic acid) derivatives with benzyl (Bz-75) groups, were synthesized to prepare the polymeric micelles for [(3)H]ATRA incorporation. ATRA were dissolved in mouse serum to analyze their inherent distribution. After intravenous administration, the blood concentration of [3H] ATRA in liposomes and polymeric micelles (Bz-75) was higher than that of inherent [3H]ATRA, suggesting that liposomes and polymeric micelles (Bz-75) control the distribution of ATRA. Pharmacokinetic analysis demonstrated that [3H]ATRA incorporated in polymeric micelles (Bz-75) exhibit the largest AUC(blood) and lowest hepatic clearance of ATRA, suggesting that polymeric micelles (Bz-75) are an effective ATRA carrier system for acute promyelocytic leukemia (APL) therapy. These results have potential implications for the design of ATRA carriers for APL patients.

Lipid Carrier Systems for Targeted Drug and Gene Delivery

For effective chemotherapy, it is necessary to deliver therapeutic agents selectively to their target sites, since most drugs are associated with both beneficial effects and side effects. The use of lipid dispersion carrier systems, such as lipid emulsions and liposomes, as carriers of lipophilic drugs has attracted particular interest. A drug delivery system can be defined as a methodology for manipulating drug distribution in the body. Since drug distribution depends on the carrier, administration route, particle size of the carrier, lipid composition of the carrier, electric charge of the carrier and ligand density of the targeting carrier, these factors must be optimized. Recently, the lipid carrier system has also been applied to gene delivery systems for gene therapy. However, in both drug and gene medicine cases, a lack of cell-selectivity limits the wide application of this kind of drug and/or gene therapy. Therefore, lipid carrier systems for targeted drug and gene delivery must be developed for the rational therapy. In this review, we shall focus on the progress of research into lipid carrier systems for drug and gene delivery following systemic or local injection.