Development of Apremilast Nanoemulsion-Loaded Chitosan Gels: In Vitro Evaluations and Anti-Inflammatory and Wound Healing Studies on a Rat Model

Formulation development of nanostructured lipid carrier-based nanogels encapsulating tacrolimus for sustained therapy of psoriasis

The goal of this study was to formulate tacrolimus nanogel based on nanostructured lipid carrier (NLC) in order to improve the efficacy, aesthetic, and patient compliance for the treatment of psoriasis. The microemulsion method was used to create phase diagrams and NLCs were prepared using points obtained from the microemulsion region and characterized. The gelling agent carbopol was used to develop an NLC-based nanogel. The pH, drug assay, viscosity, spreadability, and in vitro release of the nanogel, were evaluated. Ex vivo cytotoxicity of the formulation was assessed in murine fibroblast cells. Oxazolone and imiquimod models of psoriasis were used to assess the effectiveness of the nanogel. The NLCs exhibited a submicron particle size of 320 ± 10 nm, a low polydispersity index (<0.3), and a zeta potential of -19.4 mV. Morphological analysis revealed spherical nanoparticles with an encapsulation efficiency of 60 ± 3 %. The nanogel maintained a pH of 6.0 ± 0.5 and possessed a remarkable drug content of 99.73 ± 1.4 %. It exhibited pseudoplastic flow behaviour, ensuring easy spreadability, and demonstrated sustained drug release exceeding 90 % over a 24-hr period. Ex vivo cytotoxicity assessments revealed that the nanogel was safe because no cell death was induced. Nanogel resolved psoriatic blisters, was non-irritating and improved skin elasticity. The favorable properties, safety profile, and remarkable efficacy show the potential of the nanogel as a patient-friendly and effective therapeutic option for psoriasis treatment.

Conversion of liquid chitosan-based nanoemulsions into inhalable solid microparticles: Process challenges with polysaccharide

Solid particles ≤5 μm are essential to allow lower lung deposition and macrophage phagocytosis of anti-tubercular drugs. Decorating liquid nanoemulsion of anti-tubercular drug with macrophage-specific chitosan and chitosan-folate conjugate and spray drying the nanoemulsion with lactose produced oversized solid particles due to polysaccharide binding effects. This study designed solid nanoemulsion using lactose as the primary solid carrier and explored additives and spray-drying variables to reduce the binding and particle growth effects of chitosan. Deposition of magnesium stearate on lactose negated chitosan-inducible excessive lactose-liquid nanoemulsion binding and solid particle growth. Moderating the adhesion of chitosan-decorated liquid nanoemulsion onto lactose produced smooth-surface solid microparticles (size: 5.45 ± 0.26 μm; roughness: ∼80 nm) with heterogeneous size (span: 1.87 ± 1.21) through plasticization of constituent materials of nanoemulsion and lactose involving OH/N-H, C-H, CONH and/or COO moieties. Smaller solid particles could attach onto the larger particles with minimal steric hindrance by smooth surfaces. Together with round solid particulate structures (circularity: 0.919 ± 0.002), good pulmonary inhalation beneficial for treatment of pulmonary tuberculosis as well as other diseases is conferred.

Enhanced Apigenin Dissolution and Effectiveness Using Glycyrrhizin Spray-Dried Solid Dispersions Filled in 3D-Printed Tablets

This study aimed to prepare glycyrrhizin-apigenin spray-dried solid dispersions and develop PVA filament-based 3D printlets to enhance the dissolution and therapeutic effects of apigenin (APN); three formulations (APN1-APN3) were proportioned from 1:1 to 1:3. A physicochemical analysis was conducted, which revealed process yields of 80.5-91% and APN content within 98.0-102.0%. FTIR spectroscopy confirmed the structural preservation of APN, while Powder-XRD analysis and Differential Scanning Calorimetry indicated its transformation from a crystalline to an amorphous form. APN2 exhibited improved flow properties, a lower Angle of Repose, and Carr's Index, enhancing compressibility, with the Hausner Ratio confirming favorable flow properties for pharmaceutical applications. In vitro dissolution studies demonstrated superior performance with APN2, releasing up to 94.65% of the drug and revealing controlled release mechanisms with a lower mean dissolution time of 71.80 min and a higher dissolution efficiency of 19.2% compared to the marketed APN formulation. This signified enhanced dissolution and improved therapeutic onset. APN2 exhibited enhanced antioxidant activity; superior cytotoxicity against colon cancer cells (HCT-116), with a lower IC50 than APN pure; and increased antimicrobial activity. A stability study confirmed the consistency of APN2 after 90 days, as per ICH, with an f2 value of 70.59 for both test and reference formulations, ensuring reliable pharmaceutical development. This research underscores the potential of glycyrrhizin-apigenin solid dispersions for pharmaceutical and therapeutic applications, particularly highlighting the superior physicochemical properties, dissolution behavior, biological activities, and stability of APN2, while the development of a 3D printlet shell offers promise for enhanced drug delivery and therapeutic outcomes in colon cancer treatment, displaying advanced formulation and processing techniques.

Bilateral punctate keratitis and hurricane keratopathy following apremilast therapy

Purpose

To report a unique case of bilateral punctate keratitis consistent with hurricane keratopathy during apremilast therapy.

Observations

A 49-year-old female presented with severe, painful, bilateral, punctate keratitis following five months of apremilast therapy. The past ocular history was noncontributory. The past medical history included psoriasis refractory to topical corticosteroids. The patient subsequently received systemic apremilast therapy and noted improvement in her psoriatic rash. Five months later the patient presented to an outside eye care provider complaining of three weeks of progressive photophobia associated with pain and redness in both eyes. On examination, the patient had decreased visual acuity with diffuse conjunctival injection and punctate epithelial erosions in a whorl-like pattern in both eyes. The remainder of the ophthalmic exam was unremarkable. The patient was started on topical moxifloxacin drops, erythromycin ointment, and preservative free artificial tears, but did not improve. Apremilast was then discontinued and topical prednisolone was added once per day. Ten weeks after discontinuation of apremilast and topical steroid therapy, the patient had recovered normal vision with an intact and normal corneal epithelium.

Conclusions and Importance

This is the first case report of cornea epithelial keratitis resembling hurricane keratopathy associated with apremilast treatment and should be recognized as a possible side effect of therapy with this class of drug.

Carboxymethyl cellulose/poloxamer gels enriched with essential oil and Ag nanoparticles: promising wound dressings

Aim: Essential oils are promising antibacterial and wound-healing agents that should be explored for the design of wound dressings. Materials & methods: Topical gels prepared from a combination of carboxymethyl cellulose and poloxamer were incorporated with tea tree and lavender oil together with Ag nanoparticles. In vitro release, cytotoxicity, antibacterial, and wound healing studies were performed. Results: The gels displayed good spreadability with viscosity in the range of 210-1200 cP. The gels displayed promising antibacterial activity against selected Gram-positive and Gram-negative bacteria used in the study. The % cell viability of the gels was more than 90.83%. Conclusion: The topical gels displayed excellent wound closure in vitro revealing that they are potential wound dressings for bacteria-infected wounds.

Diosmin-Loaded Nanoemulsion-Based Gel Formulation: Development, Optimization, Wound Healing and Anti-Inflammatory Studies

The wound-healing process is complex and prone to interruption or failure, which can result in the development of chronic wounds that never heal. This can be overcome by seeking prompt medical attention, which will reduce the likelihood of complications and speed up the healing of the cutaneous wound. It has been established that functionalized engineered biomaterials are a possible strategy for starting skin wound care. The purpose of the current study is to develop a diosmin (DSM)-loaded nanoemulsion (NE)-based gel formulation and to investigate its wound healing and anti-inflammatory activity on rats. The DSM-loaded NEs (F1-F17) were developed and optimized with the help of Box-Behnken Design Expert. The DSM-Nes were developed using lauroglycol 90 (LG90^®) as oil, Tween-80 as surfactant and transcutol-HP (THP) as co-surfactant. The optimized Nes showed globule size (41 ± 0.07 nm), polydispersity index (PDI) (0.073 ± 0.008) and percentage of entrapment efficiency (%EE) (87 ± 0.81%). This optimized DSM-loaded NEs (F1) was further evaluated and incorporated into 1% carbopol 940 gel. F1-loaded gel was then characterized for drug content, spreadability, in vitro release, wound healing, and anti-inflammatory studies. The developed gel of DSM was found to show significantly better (p < 0.05) wound-healing and anti-inflammatory activity.

Design and Evaluation of Solid Lipid Nanoparticles Loaded Topical Gels: Repurpose of Fluoxetine in Diabetic Wound Healing

The current study aimed to prepare a topical gel containing solid lipid nanoparticles (SLNs) encapsulating fluoxetine for diabetic wound healing effects. Fluoxetine (FX) was loaded into SLNs by employing an emulsion solvent evaporation technique using stearic acid as a lipid, and soya lecithin as a surfactant. SLNs were then evaluated for particle size, polydispersity index (PDI), zeta potential (ZP), percent entrapment efficiency (%EE), percent drug loading (%DL), and in vitro drug release. The optimized SLN (FS3) composed of FX (100 mg), SA (150 mg), and SA (100 mg) displayed mean particle size (467.3 ± 2.2nm), PDI (0.435 ± 0.02), ZP (-32.2 ± 4.47mV), EE (95.8 ± 3.38%), and DL (16.4 ± 2.4%). FTIR and DSC studies denote drug-polymer compatibility and the amorphous nature of FX in the SLNs. The drug release at 24 h was found to be (98.89 ± 2.57%) which followed the fickian diffusion mechanism. SLN (FS3) was further loaded into carbopol gel and tested for pH, spreadability, and extrudability of pharmaceutical parameters. In-vitro release of FX from the SLN gel and plain gel was compared, diabetic wound healing gel (DWH) showed sustained drug delivery. An in vivo study was also performed for DWH gel in streptozotocin-induced diabetic rats. Histopathological examination exhibited DWH gel-treated wounds have increased hydroxyproline, cellular proliferation, a rise in the number of blood vessels, and the level of collagen synthesis. Thus, DWH gel-loaded SLN encapsulated with FX could be a potential carrier for the effective treatment and management of diabetic wounds.

Nanoemulsion-Based Hydrogels and Organogels Containing Propolis and Dexpanthenol: Preparation, Characterization, and Comparative Evaluation of Stability, Antimicrobial, and Cytotoxic Properties

Recently, nanoemulsion-based gels have become very popular for dermal drug delivery, overcoming the disadvantages of conventional semi-solid drug forms. The aim of this study is to prepare and characterize nanoemulsion-based hydrogels and organogels containing combined propolis and dexpanthenol, and to compare their stability, antimicrobial, and cytotoxicity properties. Within the scope of characterization studies, organoleptic properties, drug content, morphology, pH, gel-sol conversion temperature, spreadability, viscosity, FT-IR, and release properties were evaluated in hydrogels and organogels. The characterization studies carried out were subjected to short-term stability evaluation at room temperature and refrigerator for 3 months. While no phase separation was observed in any of the formulations kept in the refrigerator, phase separation was observed in four formulations kept at room temperature. The release study successfully obtained an extended release for propolis and dexpanthenol. In the antimicrobial susceptibility study, Hydrogel 1 showed activity against S. aureus, while Organogel 1 showed activity against both S. aureus and S. epidermidis. In the cytotoxicity study against HDFa cells, both Hydrogel 1 and Organogel 1 were found to be nontoxic at low doses. These hydrogels and organogels, which contain propolis and dexpanthenol in combination for the first time, are promising systems that can be used in wound and burn models in the future.

Crisaborole Loaded Nanoemulsion Based Chitosan Gel: Formulation, Physicochemical Characterization and Wound Healing Studies

The development of an effective gel capable of treating eczema remains a challenge in medicine. Because of its greater retention in the affected area, good absorption of wound exudates, and induction of cell growth, nanogel is widely investigated as a topical preparation. Chitosan gel based on nanoemulsions has received much attention for its use in wound healing. In this study, four formulae (CRB-NE1-CRB-NE4) of crisaborole-loaded nanoemulsions (CRB-NEs) were developed using lauroglycol 90 as an oil, Tween-80 as a surfactant, and transcutol-HP (THP) as a co-surfactant. The prepared NEs (CRB-NE1-CRB-NE4) were evaluated for their physicochemical properties. Based on vesicle size (64.5 ± 5.3 nm), polydispersity index (PDI) (0.202 ± 0.06), zeta potential (ZP, −36.3 ± 4.16 mV), refractive index (RI, 1.332 ± 0.03), and percent transmittance (% T, 99.8 ± 0.12) was optimized and further incorporated into chitosan (2%, w/w) polymeric gels. The CRB-NE1-loaded chitosan gel was then evaluated for its drug content, spreadability, in-vitro release, flux, wound healing, and anti-inflammatory studies. The CRB-NE1-loaded chitosan gel exhibited a flux of 0.211 mg/cm²/h, a drug release of 74.45 ± 5.4% CRB released in 24 h with a Korsmeyer-Peppas mechanism release behavior. The CRB-NE1-loaded gel exhibited promising wound healing and anti-inflammatory activities.