Transdermal applications of ethosomes - a detailed review

Revolutionizing rheumatoid arthritis treatment with emerging cutaneous drug delivery systems: overcoming the challenges and paving the way forward

Rheumatoid arthritis (RA) is a chronic inflammatory disorder of the articulating joints. Though considerable progress has been made in understanding the disease in the past 50 years, its pathogenesis remains unclear. The therapies for RA, such as nonsteroidal anti-inflammatory drugs, disease-modifying antirheumatic drugs, and glucocorticoids through conventional therapeutic delivery systems by percutaneous, intra-articular, intraperitoneal, oral, and intravenous administration, have shown their own disadvantages, which eventually reduce patient compliance for long-term therapy. Recently, drug delivery via a topical or transdermal route has gained attention as an alternative to the conventional approach. Though skin acts as a barrier for the delivery of drugs due to its structure, various permeation pathways are manipulated to enhance the drug delivery across or into the skin. However, poor skin retention is the reason for the failure of many conventional topical dosage forms, such as gels, sprays, and creams. Hence, there is an urgent need for conquering the skin boundary to improve skin partitioning. Nanotechnology is a developing and dynamic field gaining popularity in the nanoscale design. This review extensively describes the potential of various nanoformulations, such as vesicular systems, lipid nanoparticles, and polymeric nanoparticles, with a targeted approach to deliver the drugs to the inflamed joint region. Limelight has also been provided to next-generation approaches like surface modification, stimuli-responsive formulations, multifunctional carrier systems, microneedles, and microsponge systems. Physical methods for enhancing the transdermal delivery, such as electroporation and sonophoresis, and emerging treatment therapies, such as gene therapy, photothermal therapy, and photodynamic therapy, have been evaluated to enhance the treatment efficacy. The clinical status, patents and current challenges associated with nanotechnology and the future prospects of targeted drug delivery have also been discussed.

Transdermal delivery of natural products against atopic dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin condition. Natural products have gained traction in AD treatment due to their accessibility, low toxicity, and favorable pharmacological properties. However, their application is primarily constrained by poor solubility, instability, and limited permeability. The transdermal drug delivery system (TDDS) offers potential solutions for transdermal delivery, enhanced penetration, improved efficacy, and reduced toxicity of natural drugs, aligning with the requirements of modern AD treatment. This review examines the application of hydrogels, microneedles (MNs), liposomes, nanoemulsions, and other TDDS-carrying natural products in AD treatment, with a primary focus on their effects on penetration and accumulation in the skin. The aim is to provide valuable insights into the treatment of AD and other dermatological conditions.

Ethosomes as a carrier for transdermal drug delivery system: methodology and recent developments

Transdermal drug delivery systems (TDDS) have received significant attention in recent years. TDDS are flexible systems that transport active components to the skin for either localized or systemic delivery of drugs through the skin. Among the three main layers of skin, the outermost layer, called the stratum corneum (SC), prevents the entry of water-loving bacteria and drugs with a high molecular weight. The challenge lies in successfully delivering drugs through the skin, which crosses the stratum corneum. The popularity of lipid-based vesicular delivery systems has increased in recent years due to their ability to deliver both hydrophilic and hydrophobic drugs. Ethosomes are specialized vesicles made of phospholipids that can store large amounts of ethanol. Ethosome structure and substance promote skin permeability and bioavailability. This article covers ethosome compositions, types, medication delivery techniques, stability, and safety. In addition to this, an in-depth analysis of the employment of ethosomes in drug delivery applications for a wide range of diseases has also been discussed. This review article highlights different aspects of ethosomes, such as their synthesis, characterization, marketed formulation, recent advancements in TDDS, and applications.

Transdermal delivery of iguratimod and colchicine ethosome by dissolving microneedle patch for the treatment of recurrent gout

This study introduces a novel approach of repetitive modeling to simulate the pathological process of recurrent gout attacks in humans. This methodology addresses the instability issues present in rat models of gout, providing a more accurate representation of the damage recurrent gout episodes inflict on human skeletal systems. A soluble nanoneedle system encapsulating colchicine and iguratimod ethosomal formulations was developed. This system aims to modulate inflammatory cytokines and inhibit osteoclast activity, thereby treating inflammatory pain and bone damage associated with recurrent gout. Additionally, a comprehensive evaluation of the microneedles' appearance, morphology, mechanical properties, and penetration capability confirmed their effectiveness in penetrating the stratum corneum. Dissolution tests and skin irritation assessments demonstrated that these microneedles dissolve rapidly without irritating the skin. In vitro permeation studies indicated that transdermal drug delivery via these microneedles is more efficient and incurs lower drug loss compared to traditional topical applications. In vivo pharmacodynamic assessments conducted in animal models revealed significant analgesic and anti-inflammatory effects when both types of microneedles were used together. Further analyses, including X-ray imaging, hematoxylin and eosin (H&E) staining, Safranin-O/fast green staining, tartrate-resistant acid phosphatase staining, and quantification of osteoclasts, confirmed the bone-protective effects of the microneedle combination. In conclusion, the findings of this research underscore the potential of this novel therapeutic approach for clinical application in the treatment of recurrent gout.

Karanjin-loaded soya lecithin-based ethosomal nanogel for the therapeutic intervention of psoriasis: formulation development, factorial design based-optimization,in vitroandin vivoassessment

This study aimed to develop and optimize karanjin-loaded ethosomal nanogel formulation and evaluate its efficacy in alleviating symptoms of psoriasis in an animal model induced by imiquimod. These karanjin-loaded ethosomal nanogel, were formulated to enhance drug penetration into the skin and its epidermal retention. Karanjin was taken to formulate ethosomes due to its potential ani-psoriatic activity. Ethosomes were formulated using the cold method using 32full factorial designs to optimize the formulation components. 9 batches were prepared using two independent variablesX1: concentration of ethanol andX2: concentration of phospholipid whereas vesicle size (Y1) and percentage entrapment efficiency (Y2) were selected as dependent variables. All the dependent variables were found to be statistically significant. The optimized ethosomal suspension (B3) exhibited a vesicle size of 334 ± 2.89 nm with an entrapment efficiency of 94.88 ± 1.24% and showed good stability. The morphology of vesicles appeared spherical with smooth surfaces through transmission electron microscopy analysis. X-ray diffraction analysis confirmed that the drug existed in an amorphous state within the ethosomal formulation. The optimized ethosome was incorporated into carbopol 934 to develop nanogel for easy application on the skin. The nanogel underwent characterization for various parameters including spreadability, viscosity, pH, extrudability, and percentage drug content. The ethosomal formulation remarkably enhanced the skin permeation of karanjin and increased epidermal retention of the drug in psoriatic skin compared to marketed preparation and pure drug. A skin retention study showed that ethosomal nanogel formulation has 48.33% epidermal retention in 6 h.In vivo,the anti-psoriatic activity of karanjin ethosomal nanogel demonstrated significant improvement in psoriasis, indicated by a gradual decrease in skin thickness and scaling as reflected in the Psoriasis Severity Index grading. Therefore, the prepared ethosomal nanogel is a potential vehicle for improved topical delivery of karanjin for better treatment of psoriasis.

Feeding the Body Through the Skin: Ethosomes and Transethosomes as a New Topical Delivery System for Bioactive Compounds

Because the feeding of our body through the oral route can be associated with many drawbacks due to the degradation of natural molecules during transit in the gastrointestinal tract, a transdermal delivery strategy, usually employed in the pharmaceutical field, can present an effective alternative for delivery of bioactives and nutrients from foods. In this review, the chance to feed the body with nutritive and bioactive molecules from food through transdermal administration is discussed. Various nanotechnological devices employed for topical and transdermal delivery of bioactive compounds are described. In addition, mechanisms underlying their potential use in the delivery of nutritive molecules, as well as their capability to efficaciously reach the dermis and promote systemic distribution, are detailed.

Application of biomacromolecule-based passive penetration enhancement technique in superficial tumor therapy: A review

Transdermal drug delivery (TDD) has shown great promise in superficial tumor therapy due to its noninvasive and avoidance of the first-pass effect. Especially, passive penetration enhancement technique (PPET) provides the technical basis for TDD by temporarily altering the skin surface structure without requiring external energy. Biomacromolecules and their derived nanocarriers offer a wide range of options for PPET development, with outstanding biocompatibility and biodegradability. Furthermore, the abundant functional groups on biomacromolecule surfaces can be modified to yield functional materials capable of targeting specific sites and responding to stimuli. This enables precise drug delivery to the tumor site and controlled drug release, with the potential to replace traditional drug delivery methods and make PPET-related personalized medicine a reality. This review focuses on the mechanism of biomacromolecules and nanocarriers with skin, and the impact of nanocarriers' surface properties of nanocarriers on PPET efficiency. The applications of biomacromolecule-based PPET in superficial tumor therapy are also summarized. In addition, the advantages and limitations are discussed, and their future trends are projected based on the existing work of biomacromolecule-based PPET.

Reassembly of the vesicular structure of niosomes after their destruction in a mechanical field

This paper presents, for the first time, evidence for vesicle destruction and payload loss at the stage of purification of niosome dispersions by centrifugation, an important operation in the assembly of vesicular materials. The ability of niosomes of different compositions to reassemble, i.e., to restore the vesicular structure after destruction in the field of centrifugal forces, was demonstrated by dynamic light scattering and fluorescence spectroscopy. The kinetics of reassembly of vesicular structures is determined by the strength of the centrifugal field and the composition of niosomes. In contrast to ternary compositions, where particle size and modality are essentially unchanged after redispersion of the precipitate resulting from centrifugation, niosome dispersions containing anionic dicetyl phosphate includes micron-sized particles after redispersion, which vary in size over a wide range throughout the observation period. The reassembly process is complicated by the presence of charge on the surface of the niosomes. Elastic niosomes - ethosomes have been synthesised which, due to the high deformability of the shells, are less susceptible to destruction in the centrifugal field and retain the contents of the aqueous core. Using the "energy landscape" approximation, it is shown that vesicular structures assembled during hydration and reassembled after their centrifugation occupy different positions in the energetic pathway of their preparation. The results obtained should also be taken into account when determining the entrapment efficiency, since this procedure uses centrifugation to separate the load. It is important to note that the physical stability of niosomes, which is usually considered in terms of the functional activity of particles, is manifest and should be considered at the material preparation stage.

Ethosomes: a potential nanovesicular carrier to enhancing the drug delivery against skin barriers

Ethosomes, which are liposomes like structures, mainly composed primarily of ethanol, have attracted considerable attention due to their potential to enhance the drug permeation via skin. The article discusses the formulation and preparation methods of ethosomes, offering insights into the various factors that influence their size, shape, and stability. Moreover, it explores the techniques used to assess the physicochemical properties of ethosomes and their impact on drug delivery effectiveness. The article also elucidates the mechanism by which ethosomes enhance skin permeation, emphasising their ability to modify the lipid structure and fluidity of the stratum corneum. Additionally, the review investigates the applications of ethosomes in diverse drug delivery scenarios, including the delivery of small molecules, peptides, and phytoconstituents. It highlights the potential of ethosomes to improve drug bioavailability, extend drug release, and achieve targeted delivery to specific skin layers or underlying tissues.

Engineering aspects of lipid-based delivery systems: In vivo gene delivery, safety criteria, and translation strategies

Defects in the genome cause genetic diseases and can be treated with gene therapy. Due to the limitations encountered in gene delivery, lipid-based supramolecular colloidal materials have emerged as promising gene carrier systems. In their non-functionalized form, lipid nanoparticles often demonstrate lower transgene expression efficiency, leading to suboptimal therapeutic outcomes, specifically through reduced percentages of cells expressing the transgene. Due to chemically active substituents, the engineering of delivery systems for genetic drugs with specific chemical ligands steps forward as an innovative strategy to tackle the drawbacks and enhance their therapeutic efficacy. Despite intense investigations into functionalization strategies, the clinical outcome of such therapies still needs to be improved. Here, we highlight and comprehensively review engineering aspects for functionalizing lipid-based delivery systems and their therapeutic efficacy for developing novel genetic cargoes to provide a full snapshot of the translation from the bench to the clinics. We outline existing challenges in the delivery and internalization processes and narrate recent advances in the functionalization of lipid-based delivery systems for nucleic acids to enhance their therapeutic efficacy and safety. Moreover, we address clinical trials using these vectors to expand their clinical use and principal safety concerns.

Transdermal administration of farnesol-ethosomes enhances the treatment of cutaneous candidiasis induced by Candida albicans in mice

Cutaneous candidiasis, caused by Candida albicans, is a severe and frustrating condition, and finding effective treatments can be challenging. Therefore, the development of farnesol-loaded nanoparticles is an exciting breakthrough. Ethosomes are a novel transdermal drug delivery carrier that incorporates a certain concentration (10-45%) of alcohols into lipid vesicles, resulting in improved permeability and encapsulation rates compared to conventional liposomes. Farnesol is a quorum-sensing molecule involved in morphogenesis regulation in C. albicans, and these ethosomes offer a promising new approach to treating this common fungal infection. This study develops the formulation of farnesol-loaded ethosomes (farnesol-ethosomes) and assesses applications in treating cutaneous candidiasis induced by C. albicans in vitro and in vivo. Farnesol-ethosomes were successfully developed by ethanol injection method. Therapeutic properties of farnesol-ethosomes, such as particle size, zeta potential, and morphology, were well characterized. According to the results, farnesol-ethosomes demonstrated an increased inhibition effect on cells' growth and biofilm formation in C. albicans. In Animal infection models, treating farnesol-ethosomes by transdermal administration effectively relieved symptoms caused by cutaneous candidiasis and reduced fungal burdens in quantity. We also observed that ethosomes significantly enhanced drug delivery efficacy in vitro and in vivo. These results indicate that farnesol-ethosomes can provide future promising roles in curing cutaneous candidiasis.

IMPORTANCE

Cutaneous candidiasis attributed to Candida infection is a prevalent condition that impacts individuals of all age groups. As a type of microbial community, biofilms confer benefits to host infections and mitigate the clinical effects of antifungal treatments. In C. albicans, the yeast-to-hypha transition and biofilm formation are effectively suppressed by farnesol through its modulation of multiple signaling pathway. However, the characteristics of farnesol such as hydrophobicity, volatility, degradability, and instability in various conditions can impose limitations on its effectiveness. Nanotechnology holds the potential to enhance the efficiency and utilization of this molecule. Treatment of farnesol-ethosomes by transdermal administration demonstrated a very remarkable therapeutic effect against C. albicans in infection model of cutaneous candidiasis in mice. Many patients suffering fungal skin infection will benefit from this study.

Engineering nanosystems for transdermal delivery of antihypertensive drugs

To control hypertension, long-term continuous antihypertensive therapeutics are required and five classes of antihypertensive drugs are frequently involved, including diuretics, β-blockers, calcium channel blockers, angiotensin II receptor blockers, and angiotensin-converting enzyme inhibitors. Although with demonstrated clinical utility, there is still room for the improvement of many antihypertensive drugs in oral tablet or capsule dosage form, in terms of reducing systemic side effects and first-pass hepatic drug uptake. Meanwhile, nanocarrier-mediated transdermal drug delivery systems have emerged as a powerful tool for various disease treatments. With benefits such as promoting patient compliance for long-time administration, enhancing skin permeability, and reducing systemic side effects, these systems are reasonably investigated and developed for the transdermal delivery of multiple antihypertensive drugs. This review aims to summarize the literature relating to nanosystem-based transdermal antihypertensive drug delivery and update recent advances in this field, as well as briefly discuss the challenges and prospects of engineering transdermal delivery nanosystems for hypertension treatment.

Nutlin-3 Loaded Ethosomes and Transethosomes to Prevent UV-Associated Skin Damage

The skin's protective mechanisms, in some cases, are not able to counteract the destructive effects induced by UV radiations, resulting in dermatological diseases, as well as skin aging. Nutlin-3, a potent drug with antiproliferative activity in keratinocytes, can block UV-induced apoptosis by activation of p53. In the present investigation, ethosomes and transethosomes were designed as delivery systems for nutlin-3, with the aim to protect the skin against UV damage. Vesicle size distribution was evaluated by photon correlation spectroscopy and morphology was investigated by cryogenic transmission electron microscopy, while nutlin-3 entrapment capacity was evaluated by ultrafiltration and HPLC. The in vitro diffusion kinetic of nutlin-3 from ethosomes and transethosomes was studied by Franz cell. Moreover, the efficiency of ethosomes and transethosomes in delivering nutlin-3 and its protective role were evaluated in ex vivo skin explants exposed to UV radiations. The results indicate that ethosomes and transethosomes efficaciously entrapped nutlin-3 (0.3% w/w). The ethosome vesicles were spherical and oligolamellar, with a 224 nm mean diameter, while in transethosome the presence of polysorbate 80 resulted in unilamellar vesicles with a 146 nm mean diameter. The fastest nutlin-3 kinetic was detected in the case of transethosomes, with permeability coefficients 7.4-fold higher, with respect to ethosomes and diffusion values 250-fold higher, with respect to the drug in solution. Ex vivo data suggest a better efficacy of transethosomes to promote nutlin-3 delivery within the skin, with respect to ethosomes. Indeed, nutlin-3 loaded transethosomes could prevent UV effect on cutaneous metalloproteinase activation and cell proliferative response.

Unlocking the potential of cosmetic dermal delivery with ethosomes: A comprehensive review

BACKGROUND

In a world where hair loss, acne, and skin whitening are common concerns, ethosomes emerge as a captivating breakthrough in cosmetic drug delivery.

METHOD

This review provides a comprehensive overview of the ethosomal system and assesses its potential as an effective nanocarrier for delivering active ingredients to the skin. The focus is on exploring their applications in various pathologies, particularly skin disorders such as acne, hair loss, and skin pigmentation.

RESULTS

Ethosomes are a novel type of vesicular nanocarrier composed of high concentrations of ethanol (20-45%) and phospholipids. Their unique structure and composition make them an ideal choice for transporting active ingredients through the skin, offering targeted and effective treatment. The inclusion of ethanol in ethosomes' composition gives them distinctive properties, including flexibility, deformability, and stability, facilitating deep penetration into the skin and enhancing medication deposition. Moreover, ethosomes improved theoverall drug-loading capacity, and specificity of target treatment CONCLUSION: Ethosomes represent a unique and suitable approach for delivering active cosmetic ingredients in the treatment of hair loss, acne, and skin whitening, presenting a versatile alternative to traditional dermal delivery systems. Despite the challenges associated with their complex preparation and sensitivity to temperature and humidity, the remarkable potential benefits of ethosomes cannot be ignored. Further research is crucial to unlock their full potential, understand their limitations, and refine their formulations and administration methods. Ethosomes hold the promise of transforming the way we address these cosmetic concerns, offering an exciting glimpse into the future of advanced skincare solutions.

Recent advances in delivery of transdermal nutrients: A review

Nutrients provide vital functions in the body for sustained health, which have been shown to be related to the incidence, prevention and treatment of disease. However, limited bioavailability, loss of targeting specificity and the increased hepatic metabolism limit the utilization of nutrients. In this review, we highlight transdermal absorption of nutrients, which represents an opportunity to allow great use of many nutrients with promising human health benefits. Moreover, we describe how the various types of permeation enhancers are increasingly exploited for transdermal nutrient delivery. Chemical penetration enhancers, carrier systems and physical techniques for transdermal nutrient delivery are described, with a focus on combinatorial approaches. Although there are many carrier systems and physical techniques currently in development, with some tools currently in advanced clinical trials, relatively few products have achieved full translation to clinical practice. Challenges and further developments of these tools are discussed here in this review. This review will be useful to researchers interested in transdermal applications of permeation enhancers for the efficient delivery of nutrients, providing a reference for supporting the need to take more account of specific nutritional needs in specific states.

Designed Fabrication of Phloretin-Loaded Propylene Glycol Binary Ethosomes: Stability, Skin Permeability and Antioxidant Activity

Binary ethosome vesicles have been developed as flexible lipid vesicles for the enhanced physicochemical stability and skin delivery of drugs. This work aimed to prepare phloretin-loaded propylene glycol ethosomes (PHL-PGEs) to improve their stability, skin permeability and antioxidant activity. PHL-PGEs were prepared via the ethanol injection method and optimized using different weight ratios of ethanol to propylene glycol (PG). When the ethanol/PG mass ratio changed from 10:0 to 0:10, the encapsulation efficiency and stability of ethosomes increased. At a PHL concentration of 1mg/mL, the EE% was 89.42 ± 2.42 and the DL% was 4.21 ± 0.04, which exhibited their highest values. The encapsulation of the PHL in the PHL-PGEs was strengthened via XRD analysis and FTIR analysis. The results of the in vitro percutaneous permeability test demonstrated that the combined use of ethanol and PG exhibited a notable enhancement in skin permeability, and the skin retention of PHL-PGEs was 1.06 times that of PHL-ethosomes (PHL-Es) and 2.24 times that of the PHL solution. An in vitro antioxidant activity study indicated that solubility and antioxidant activity was potentiated via the nanoencapsulation of phloretin. Therefore, these results confirm the potential of this nanocarrier to enhance physicochemical stability, skin permeability and antioxidant activity.

Nanotechnology-Based Drug Delivery Systems in the Transdermal Treatment of Melanoma

The incidence rate of melanoma is dramatically increasing worldwide, raising it to the fifth most common cancer in men and the sixth in women currently. Resistance generally occurs to the agents used in chemotherapy; besides their high toxicity destroys the normal cells. This study reviewed a detailed summary of the structure, advantages, and disadvantages of nanotechnology-based drug delivery systems in the treatment of melanoma, as well as some nanocarrier applications in animal models or clinical studies. Respective databases were searched for the target keywords and 93 articles were reviewed and discussed. A close study of the liposomes, niosomes, transferosomes, ethosomes, transethosomes, cubosomes, dendrimers, cyclodextrins, solid lipid nanoparticles, and carbon nanotubes (CNTs) was conducted. It was found that these nanocarriers could inhibit metastasis and migration of melanoma cells and decrease cell viability. Conclusively, some nanocarriers like liposomes, niosomes, and transferosomes have been discussed as superior to conventional therapies for melanoma treatment.

Transethosomes: Cutting edge approach for drug permeation enhancement in transdermal drug delivery system

The skin is a major route of drug administration. Despite the high surface area of the skin, drug delivery via the skin route is problematic due to its physiological obstacles. The formulation scientist has developed a vesicular system to enhance the skin's absorption of bioactive substances. Among numerous vesicular systems, concept of transethosomes (TEs) introduced in 2012 are being tested for drug delivery to the dermis. When transferosomes and ethosomes interact, TEs are produced. It consists of water, ethanol, phospholipids, and an edge activator. Ethanol and the edge activator increase the absorption of medication through the skin. In the presence of ethanol and an edge activator, skin permeability can increase. The advantages of TEs include increased patient compliance, bypassing first-pass metabolism, including non-toxic raw components, being a noninvasive method of drug delivery, being more stable, biocompatible, biodegradable, and administered in semisolid form. TEs can be produced through the use of hot, cold, mechanical dispersion, and conventional techniques. The morphology, shape, size, zeta potential, drug loading efficiency, vesicle yield, biophysical interactions, and stability of TEs define them. Recent studies reported successful transdermal distribution of antifungal, antiviral, anti-inflammatory, and cardiovascular bioactive while using ethosomes with significant deeper penetration in skin. The review extensively discussed various claims on TEs developed by researchers, patents, and marketed ethosomes. However, till today no patens being granted on TEs. There are still lingering difficulties related to ethanol-based TEs that require substantial research to fix.

Study of the skin-penetration promoting effect and mechanism of combined system of curcumin liposomes prepared by microfluidic chip and skin penetrating peptides TD-1 for topical treatment of primary melanoma

The transdermal drug delivery system (TDDS) is an effective strategy for the treatment of melanoma with fewer side effects and good biocompatible, but the skin penetration of drugs should be further promoted. Here, we proposed a new system that combined curcumin liposomes (Cur-Lips) with skin-penetrating peptides to promote skin penetration ability. However, the preparation of Cur-Lips has drawbacks of instability and low entrapment efficiency by the traditional methods. We thus innovatively designed and applied a microfluidic chip to optimize the preparation of Cur-Lips. Cur-Lips exhibited a particle size of 106.22 ± 4.94 nm with a low polydispersity index (＜0.3) and high entrapment efficiency of 99.33 ± 1.05 %, which were prepared by the microfluidic chip. The Cur-Lips increased the skin penetration capability of Cur by 2.76 times compared to its solution in vitro skin penetration experiment. With the help of skin-penetrating peptide TD-1, the combined system further promoted the skin penetration capability by 4.48 times. The (TD-1 + Cur-Lips) system also exhibited a superior inhibition effect of the tumor to B16F10 in vitro. Furthermore, the topical application of (TD-1 + Cur-Lips) gel suppressed melanoma growth in vivo, and induced tumor cell apoptosis in tumor tissues. The skin-penetration promotion mechanism of the system was investigated. It was proved that the system could interact with the lipids and keratin on the stratum corneum to promote the Cur distribute into the stratum corneum through hair follicles and sweat glands. We proved that the microfluidic chips had unique advantages for the preparation of liposomes. The innovative combined system of liposomes and biological transdermal enhancers can effectively promote the skin penetration effect of drugs and have great potential for the prevention and treatment of melanoma.

Exploring Nanocarriers as Treatment Modalities for Skin Cancer

Cancer is a progressive disease of multi-factorial origin that has risen worldwide, probably due to changes in lifestyle, food intake, and environmental changes as some of the reasons. Skin cancer can be classified into melanomas from melanocytes and nonmelanoma skin cancer (NMSC) from the epidermally-derived cell. Together it constitutes about 95% of skin cancer. Basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (CSCC) are creditworthy of 99% of NMSC due to the limited accessibility of conventional formulations in skin cancer cells of having multiple obstacles in treatment reply to this therapeutic regime. Despite this, it often encounters erratic bioavailability and absorption to the target. Nanoparticles developed through nanotechnology platforms could be the better topical skin cancer therapy option. To improve the topical delivery, the nano-sized delivery system is appropriate as it fuses with the cutaneous layer and fluidized membrane; thus, the deeper penetration of therapeutics could be possible to reach the target spot. This review briefly outlooks the various nanoparticle preparations, i.e., liposomes, niosomes, ethosomes, transferosomes, transethosomes, nanoemulsions, and nanoparticles technologies tested into skin cancer and impede their progress tend to concentrate in the skin layers. Nanocarriers have proved that they can considerably boost medication bioavailability, lowering the frequency of dosage and reducing the toxicity associated with high doses of the medication.

Strategies for targeted gene delivery using lipid nanoparticles and cell-derived nanovesicles

Gene therapy is a promising approach for the treatment of many diseases. However, the effective delivery of the cargo without degradation in vivo is one of the major hurdles. With the advent of lipid nanoparticles (LNPs) and cell-derived nanovesicles (CDNs), gene delivery holds a very promising future. The targeting of these nanosystems is a prerequisite for effective transfection with minimal side-effects. In this review, we highlight the emerging strategies utilized for the effective targeting of LNPs and CDNs, and we summarize the preparation methodologies for LNPs and CDNs. We have also highlighted the non-ligand targeting of LNPs toward certain organs based on their composition. It is highly expected that continuing the developments in the targeting approaches of LNPs and CDNs for the delivery system will further promote them in clinical translation.

Hyaluronic Acid-Based Nanosystems for CD44 Mediated Anti-Inflammatory and Antinociceptive Activity

The nervous and immune systems go hand in hand in causing inflammation and pain. However, the two are not mutually exclusive. While some diseases cause inflammation, others are caused by it. Macrophages play an important role in modulating inflammation to trigger neuropathic pain. Hyaluronic acid (HA) is a naturally occurring glycosaminoglycan that has a well-known ability to bind with the cluster of differentiation 44 (CD44) receptor on classically activated M1 macrophages. Resolving inflammation by varying the molecular weight of HA is a debated concept. HA-based drug delivery nanosystems such as nanohydrogels and nanoemulsions, targeting macrophages can be used to relieve pain and inflammation by loading antinociceptive drugs and enhancing the effect of anti-inflammatory drugs. This review will discuss the ongoing research on HA-based drug delivery nanosystems regarding their antinociceptive and anti-inflammatory effects.

An overview of topical lipid-based and polymer-based nanocarriers for treatment of psoriasis

Psoriasis is a consistently recurring, inflammatory skin disease, affecting about 2 - 5 % of the world population. Different types of psoriasis can be observed such as guttate psoriasis, pustular psoriasis, psoriatic arthritis, scalp psoriasis, flexural psoriasis etc. Several therapeutic approaches are available for the treatment of psoriasis. However, none of them are entirely safe and effective to treat the disease without compromising patient compliance. The traditional treatment plan is associated with harmful side effects such asimmune system suppression and damage of essential organs at high doses, which poses a challenge to treat psoriasis. Novel drug delivery systems are being developed to replace traditional therapy in order to address these shortcomings. Currently, nanoformulations have gained widespread application for treatment of psoriasis. Researchers have developed different types of lipid-based nanoparticles like liposomes, niosomes, ethosomes, transethosomes, nanostructured lipid carriers and solid lipid nanoparticles. These innovative formulations provide advantages in terms of reduction in dose, dosing frequency, dose-dependency with enhanced efficacy, improved encapsulation efficiency, controlled release, increased surface area, high bioavailability and greater stratum corneum permeability. This review highlights detailed and comparative discussion of lipid-based and polymer-based nanoparticles for psoriasis along with the pathophysiology and other treatments of psoriasis.

Transethosomes: A Promising Challenge for Topical Delivery Short Title: Transethosomes for Topical Delivery

Skin provides an excellent barrier to molecular transport, as the stratum corneum is the most formidable barrier to the passage of most pharmaceuticals. Various attempts have been made to improve drug administration into the body through intact skin. Though very few routes are as attractive as the topical route, drug transport through the skin is challenging. To overcome the challenges, researchers have found a system in which the drug is encapsulated into the vesicle, penetrating deeper into the skin to hit the target site. Vesicular systems like transethosome, an ultra- deformable vesicle (UDV), tend to accumulate in the skin layers. Since transethosomes have small particle size and can easily alter the shape of vesicles compared to other vesicular systems, they can penetrate through the layers of skin. Hence, the drug encapsulated into transethosomes can easily reach the target site. Transethosomes consist of ethanol and phospholipids along with an edge activator. Ethanol and edge activator help to enhance the skin permeation of transethosomes. Various methods of preparation of transethosomes, comparison of transethosomes with other lipid vesicles, characterization of transethosomes, and application of transethosomes have been covered in this review. Transethosomes can deliver a different variety of drugs, such as anticancer, corticosteroids, proteins and peptides, analgesics.

A Comprehensive Overview of Epidemiology, Pathogenesis and the Management of Herpes Labialis

Herpes labialis remains exceedingly prevalent and is one of the most common human viral infections throughout the world. Recurrent herpes labialis evolves from the initial viral infection by herpes simplex virus type 1 (HSV-1) which subsequently presents with or without symptoms. Reactivation of this virus is triggered by psychosocial factors such as stress, febrile environment, ultraviolet light susceptibility, or specific dietary inadequacy. This virus infection is also characterized by uninterrupted transitions between chronic-latent and acute-recurrent phases, allowing the virus to opportunistically avoid immunity and warrant the transmission to other vulnerable hosts simultaneously. This review comprehensively evaluates the current evidence on epidemiology, pathogenesis, transmission modes, clinical manifestations, and current management options of herpes labialis infections.

Ex Vivo Evaluation of Ethosomes and Transethosomes Applied on Human Skin: A Comparative Study

In this study, the transdermal fate of vesicular nanosystems was investigated. Particularly, ethosomes based on phosphatidylcholine 0.9% w/w and transethosomes based on phosphatidylcholine 0.9 or 2.7% w/w plus polysorbate 80 0.3% w/w as an edge activator were prepared and characterized. The vesicle mean size, morphology and deformability were influenced by both phosphatidylcholine and polysorbate 80. Indeed, the mean diameters of ethosome were around 200 nm, while transethosome's mean diameters were 146 or 350 nm in the case of phosphatidylcholine 0.9 or 2.7%, w/w, respectively. The highest deformability was achieved by transethosomes based on phosphatidylcholine 0.9%, w/w. The three types of vesicular nanosystems were applied on explanted human skin maintained in a bioreactor. Transmission electron microscopy demonstrated that all vesicles were able to enter the skin, keeping their structural integrity. Notably, the vesicle penetration capability was influenced by their physical-chemical features. Indeed, ethosomes reached keratinocytes and even the dermis, phosphatidylcholine 0.9% transethosomes were found in keratinocytes and phosphatidylcholine 2.7% transethosomes were found only in corneocytes of the outer layer. These findings open interesting perspectives for a differentiated application of these vesicles for transdermal drug delivery as a function of the cutaneous pathology to be addressed.

Overcoming skin barriers through advanced transdermal drug delivery approaches

Upon exhaustive research, the transdermal drug delivery system (TDDS) has appeared as a potential, well-accepted, and popular approach to a novel drug delivery system. Ease of administration, easy handling, minimum systemic exposure, least discomfort, broad flexibility and tunability, controlled release, prolonged therapeutic effect, and many more perks make it a promising approach for effective drug delivery. Although, the primary challenge associated is poor skin permeability. Skin is an intact barrier that serves as a primary defense mechanism to preclude any foreign particle's entry into the body. Owing to the unique anatomical framework, i.e., compact packing of stratum corneum with tight junction and fast anti-inflammatory responses, etc., emerged as a critical physiological barrier for TDDS. Fusion with other novel approaches like nanocarriers, specially designed transdermal delivery devices, permeation enhancers, etc., can overcome the limitations. Utilizing such strategies, some of the products are under clinical trials, and many are under investigation. This review explores all dimensions that overcome poor permeability and allows the drug to attain maximum potential. The article initially compiles fundamental features, components, and design of TDDS, followed by critical aspects and various methods, including in vitro, ex vivo, and in vivo methods of assessing skin permeability. The work primarily aimed to highlight the recent advancement in novel strategies for effective transdermal drug delivery utilizing active methods like iontophoresis, electroporation, sonophoresis, microneedle, needleless jet injection, etc., and passive methods such as the use of liposomes, SLN, NLC, micro/nanoemulsions, dendrimers, transferosomes, and many more nanocarriers. In all, this compilation will provide a recent insight on the novel updates along with basic concepts, the current status of clinical development, and challenges for the clinical translation of TDDS.

Latest on biomaterial-based therapies for topical treatment of psoriasis

Psoriasis is an autoimmune inflammatory disease which is fundamentally different from dermatitis. Its treatments include topical medications and systemic drugs depending on different stages of the disease. However, these commonly used therapies are falling far short of clinical needs due to various drawbacks. More precise therapeutic strategies with minimized side effects and improved compliance are highly demanded. Recently, the rapid development of biomaterial-based therapies has made it possible and promising to attain topical psoriasis treatment. In this review, we briefly describe the significance and challenges of the topical treatment of psoriasis and emphatically overview the latest progress in novel biomaterial-based topical therapies for psoriasis including microneedles, nanoparticles, nanofibers, and hydrogels. Current clinical trials related to each biomaterial are also summarized and discussed.

Ethosomes as dermal/transdermal drug delivery systems: applications, preparation and characterization

Transdermal drug delivery systems (TDDSs) have gained substantial attention during the last decade. TDDS are versatile delivery systems in which active components are delivered to skin for local effects or systemic delivery of active pharmaceutical through the skin. Overcoming stratum corneum is the most challenging step of delivering drugs through the skin. Lipid-based vesicular delivery systems due to the capability of the delivery of both hydrophilic and hydrophobic drugs are becoming more popular during the recent years. Ethosomes are innovative, biocompatible, biodegradable and non-toxic form of lipid-based vesicles that efficiently enable to entrap drugs of various physicochemical properties. These are other forms of liposome which contain high amounts of ethanol in their structure that enabling ethosomes to efficiently penetrate through deeper layers of skin. Ethosomes have various compositions based on their type but are mainly composed of phospholipids, ethanol, water and the active components. Ethosomes are easily manufactured and they are superior compared to liposomes in terms of different aspects due to the presence of ethanol. The purpose of this review is to thoroughly focus on various aspects of ethosomes, including mechanism of penetration, advantages and disadvantages, characterisation and applications.

Formulation and Characterization of Metformin-Loaded Ethosomes for Topical Application to Experimentally Induced Skin Cancer in Mice

To achieve the best treatment of skin cancer, drug penetration inside the deepest layers of the skin is an important scientific interest. We designed an ethosome formulation that serves as a carrier for metformin and measured the in vitro skin permeation. We also aimed to measure the antitumor activity of the optimal ethosomal preparation when applied topically to chemically induced skin cancer in mice. We utilized a statistical Box-Behnken experimental design and applied three variables at three levels: lecithin concentration, cholesterol concentration and a mixture of ethanol and isopropyl alcohol concentrations. All formulations were prepared to calculate the entrapment efficiency %, zeta potential, size of the vesicles and drug release % after 1, 2, 4, 8 and 24 h. The size of the vesicles for the formulations was between 124 ± 14.2 nm and 560 ± 127 nm, while the entrapment efficiency was between 97.8 ± 0.23% and 99.4 ± 0.24%, and the drug release % after 8 h was between 38 ± 0.82% and 66 ± 0.52%. All formulations were introduced into the Box-Behnken software, which selected three formulations; then, one was assigned as an optimal formula. The in vivo antitumor activity of metformin-loaded ethosomal gel on skin cancer was greater than the antitumor activity of the gel preparation containing free metformin. Lower lecithin, high ethanol and isopropyl alcohol and moderate cholesterol contents improved the permeation rate. Overall, we can conclude that metformin-loaded ethosomes are a promising remedy for treating skin cancers, and more studies are warranted to approve this activity in other animal models of skin cancers.

Rationale utilization of phospholipid excipients: a distinctive tool for progressing state of the art in research of emerging drug carriers

Phospholipids have a high degree of biocompatibility and are deemed ideal pharmaceutical excipients in the development of lipid-based drug delivery systems, because of their unique features (permeation, solubility enhancer, emulsion stabilizer, micelle forming agent, and the key excipients in solid dispersions) they can be used in a variety of pharmaceutical drug delivery systems, such as liposomes, phytosomes, solid lipid nanoparticles, etc. The primary usage of phospholipids in a colloidal pharmaceutical formulation is to enhance the drug's bioavailability with low aqueous solubility [i.e. Biopharmaceutical Classification System (BCS) Class II drugs], Membrane penetration (i.e. BCS Class III drugs), drug uptake and release enhancement or modification, protection of sensitive active pharmaceutical ingredients (APIs) from gastrointestinal degradation, a decrease of gastrointestinal adverse effects, and even masking of the bitter taste of orally delivered drugs are other uses. Phospholipid-based colloidal drug products can be tailored to address a wide variety of product requirements, including administration methods, cost, product stability, toxicity, and efficacy. Such formulations that are also a cost-effective method for developing medications for topical, oral, pulmonary, or parenteral administration. The originality of this review work is that we comprehensively evaluated the unique properties and special aspects of phospholipids and summarized how the individual phospholipids can be utilized in various types of lipid-based drug delivery systems, as well as listing newly marketed lipid-based products, patents, and continuing clinical trials of phospholipid-based therapeutic products. This review would be helpful for researchers responsible for formulation development and research into novel colloidal phospholipid-based drug delivery systems.

Nano-traditional Chinese medicine: a promising strategy and its recent advances

Traditional Chinese Medicine (TCM) has been applied to the prevention and treatment of numerous diseases and has an irreplaceable role in rehabilitation and health care. However, the application of TCMs is drastically limited by their defects, such as single administration, poor water solubility, low bioavailability, and weak targeting capability. Recently, nanoparticles have been extensively used in resolving pharmaceutical obstacles in consideration of their large specific surface area, strong targeting capability, good sustained-release effect, etc. In this review, we first describe the limitations of TCM ingredients and two significant forms of nanotechnology applied in TCM, nanometerization of TCMs and nano-drug delivery systems for TCMs. Then, we discuss the preparation methods of nanometerization: mechanical crushing, spray drying, and high-pressure homogenization, which have been utilized to conquer the various weaknesses of TCMs. Then, recent advances in nano-drug delivery systems for TCM ingredients are discussed, including lipid-based nanocarriers, polymeric nanoparticles, inorganic nanocarriers, hybrid nanoparticles, and TCM self-assembled nanoparticles. Finally, the future challenges and perspectives of TCM formula complexity and the limitations of nanocarriers are also discussed. Better understanding the function of nanotechnology in TCM will help to modernize Chinese medicine and broaden the application of nano-TCM in the clinic.

Suppression of Melanoma Growth in a Murine Tumour Model Using Orthosiphon stamineus Benth. Extract Loaded in Ethanolic Phospholipid Vesicles (Spherosome

BACKGROUND

Orthosiphon stamineus Benth (O.S) is a traditional south-east Asian herb. The extract of O.S is used in the formulation of ethanolic nanolipid vesicle system to have considerable potential for tumour therapeutics.

METHOD

The research objective is to develop and characterise the anticancer and antiangiogenic effect of O.S extract in the form of nano-ethanolic spherosomes (ESP) using phospholipids in melanoma. Spherosomes formulation of O.S was developed using the thin-film re-hydration method and converted to gel using Acrypol 1%. The formulations were subjected to optimisation and physical-chemical characterisations like particle size, surface charge, DSC, FTIR, TEM. Cytotoxicity of O.S and ESP were studied using an endothelial cell line (EA. hy926). Furthermore, anti-melanoma effect of O.S spherosome gel was studied in albino mice after topical administration.

RESULTS

ESP-6 with the ratio of extract (O.S): cholesterol: phospholipid (1: 6: 0.5) showed the highest entrapment efficiency (80.56 ± 0.84%) using ultraviolet spectroscopy. In-vivo permeation/penetration studies revealed deeper absorption of ESP-6 compared with a hydroethanolic gel of O.S. In-vitro and in vivo anti-melanoma studies demonstrated the significant tumour-suppressing effect of ESP-6 on murine melanoma. Percentage inhibition of tumour growth by O.S and ESP-6 at 3000 mg/kg showed 63.98 ± 7.86% and 87.76 ± 7.90%, respectively.

CONCLUSION

Spherosome vesicles were developed with a smooth surface. The results demonstrated that O.S extract showed no toxicity when tested on the endothelial cell line. O.S loaded in spherosomes has the potential to lower the growth of melanoma in mice. The spherosomes loaded with O.S do not promote tumour growth or act as antiangiogenetic in melanoma.

The Optimized Delivery of Triterpenes by Liposomal Nanoformulations: Overcoming the Challenges

The last decade has witnessed a sustained increase in the research development of modern-day chemo-therapeutics, especially for those used for high mortality rate pathologies. However, the therapeutic landscape is continuously changing as a result of the currently existing toxic side effects induced by a substantial range of drug classes. One growing research direction driven to mitigate such inconveniences has converged towards the study of natural molecules for their promising therapeutic potential. Triterpenes are one such class of compounds, intensively investigated for their therapeutic versatility. Although the pharmacological effects reported for several representatives of this class has come as a well-deserved encouragement, the pharmacokinetic profile of these molecules has turned out to be an unwelcomed disappointment. Nevertheless, the light at the end of the tunnel arrived with the development of nanotechnology, more specifically, the use of liposomes as drug delivery systems. Liposomes are easily synthesizable phospholipid-based vesicles, with highly tunable surfaces, that have the ability to transport both hydrophilic and lipophilic structures ensuring superior drug bioavailability at the action site as well as an increased selectivity. This study aims to report the results related to the development of different types of liposomes, used as targeted vectors for the delivery of various triterpenes of high pharmacological interest.

Optimizing and Evaluating the Transdermal Permeation of Hydrocortisone Transfersomes Formulation Based on Digital Analysis of the In Vitro Drug Release and Ex Vivo Studies

BACKGROUND

Transfersomes can be used to enhance transdermal drug delivery due to their flexibility and ability to incorporate various molecules. For example, hydrocortisone (HC), a corticosteroid, is taken by different routes and serves as immunosuppressive, anticancer, and antiallergenic; however, it is poorly absorbed by the skin.

OBJECTIVE

Therefore, the current study suggested HC-loaded transfersomes as an alternative route of administration for reaching deeper skin layers or systemic circulation, to reduce the side effects of HC and improve its bioavailability.

METHODS

HC transfersomes were prepared by the thin-film hydration method and characterized for their vesicular size, zeta potential, drug entrapment efficiency, elasticity, FTIR spectroscopy, in vitro drug release, ex vivo permeation, and irritancy in rabbits. The optimized formulation, F15 (containing HC 20 mg, egg phosphatidylcholine (EPC) 400 mg, and 75 mg of Span 80), was chosen because it showed the highest (p< 0.05) EE% (60.4±0.80) and optimized sustained in vitro drug release (Q8 = 87.9±0.6%).

RESULTS

Extensive analysis of the drug release data from all formulas was performed using the DDSolver software which quantitatively confirmed the successful formulation. The Weibull equation was the best model to fit the release data compared to others, and the release mechanism was Fickian diffusion.

CONCLUSION

The simulated pharmacokinetic parameters showed that F15 had the highest AUC, MDT, and DE. Furthermore, F15 significantly enhanced HC permeation by 12-folds compared to the control through the excised rat's skin. The skin irritancy test has proven F15 safety and skin compatibility.

Mapping hair follicle-targeted delivery by particle systems: What has science accomplished so far?

The importance of the hair follicle in the process of cutaneous drug penetration has been established since this skin appendage was recognized as an entry point for topically applied substances. A comprehensive review on the hair follicle as a target per se is here provided, exploring the current knowledge on both targeted regions and delivery systems that take advantage of this permeation route. The follicular penetration is a complex process, whose effectiveness and efficiency strongly depends on a diversity of different factors including follicular density and size, activity status of hair follicles and physicochemical properties of the topically applied substances. Nanocarriers represent a heterogeneous assembly of molecules organized into particles and they have revolutionized drug delivery in several areas of medicine, pharmacology and cosmetics. As they possess an inherent ability to use the follicular route, they are reviewed here having in perspective the hair follicle zones that they are able to reach as reported. In this way, a follicular road map for the different delivery systems was compiled to assist as a guiding tool for those that have interest in the development and/or application of such delivery systems for hair and skin treatment or care.

Rutin-Loaded Nanovesicles for Improved Stability and Enhanced Topical Efficacy of Natural Compound

Rutin is a natural compound with several pharmacological effects. Among these, antioxidant activity is one of the best known. Despite its numerous benefits, its topical application is severely limited by its physicochemical properties. For this reason, the use of suitable systems could be necessary to improve its delivery through skin, thus enhancing its pharmacological effects. In this regard, the aim of this work is to optimize the ethosomal dispersion modifying both lipid and ethanol concentrations and encapsulating different amounts of rutin. Characterization studies performed on the realized systems highlighted their great stability properties. Studies of encapsulation efficiency and loading degree allowed us to identify a better formulation (EE% 67.5 ± 5.2%, DL% 27 ± 1.7%), which was used for further analyses. The data recorded from in vitro studies showed that the encapsulation into these nanosystems allowed us to overcome the photosensitivity limitation of rutin. Indeed, a markable photostability of the loaded formulation was recorded, compared with that reported from the free rutin solution. The efficacy of the nanosystems was finally evaluated both in vitro on keratinocyte cells and in vivo on human healthy volunteers. The results confirmed the potentiality of rutin-loaded nanosystems for skin disease, mainly related to their anti-inflammatory and antioxidant effects.

The technology of transdermal delivery nanosystems: from design and development to preclinical studies

Transdermal administration has gained much attention due to the remarkable advantages such as patient compliance, drug escape from first-pass elimination, favorable pharmacokinetic profile and prolonged release properties. However, the major limitation of these systems is the limited skin penetration of the stratum corneum, the skin's most important barrier, which protects the body from the insertion of substances from the environment. Transdermal drug delivery systems are aiming to the disruption of the stratum corneum in order for the active pharmaceutical ingredients to enter successfully the circulation. Therefore, nanoparticles are holding a great promise because they can act as effective penetration enhancers due to their small size and other physicochemical properties that will be analyzed thoroughly in this report. Apart from the investigation of the physicochemical parameters, a comparison between the different types of nanoparticles will be performed. The complexity of skin anatomy and the unclear mechanisms of penetration should be taken into consideration to reach some realistic conclusions regarding the way that the described parameters affect the skin permeability. To the best of the authors knowledge, this is among the few reports on the literature describing the technology of transdermal delivery systems and how this technology affects the biological activity.

Lipid Nanoparticulate Drug Delivery Systems: Recent Advances in the Treatment of Skin Disorders

The multifunctional role of the human skin is well known. It acts as a sensory and immune organ that protects the human body from harmful environmental impacts such as chemical, mechanical, and physical threats, reduces UV radiation effects, prevents moisture loss, and helps thermoregulation. In this regard, skin disorders related to skin integrity require adequate treatment. Lipid nanoparticles (LN) are recognized as promising drug delivery systems (DDS) in treating skin disorders. Solid lipid nanoparticles (SLN) together with nanostructured lipid carriers (NLC) exhibit excellent tolerability as these are produced from physiological and biodegradable lipids. Moreover, LN applied to the skin can improve stability, drug targeting, occlusion, penetration enhancement, and increased skin hydration compared with other drug nanocarriers. Furthermore, the features of LN can be enhanced by inclusion in suitable bases such as creams, ointments, gels (i.e., hydrogel, emulgel, bigel), lotions, etc. This review focuses on recent developments in lipid nanoparticle systems and their application to treating skin diseases. We point out and consider the reasons for their creation, pay attention to their advantages and disadvantages, list the main production techniques for obtaining them, and examine the place assigned to them in solving the problems caused by skin disorders.

Do Lipid-based Nanoparticles Hold Promise for Advancing the Clinical Translation of Anticancer Alkaloids?

Since the commercialization of morphine in 1826, numerous alkaloids have been isolated and exploited effectively for the betterment of mankind, including cancer treatment. However, the commercialization of alkaloids as anticancer agents has generally been limited by serious side effects due to their lack of specificity to cancer cells, indiscriminate tissue distribution and toxic formulation excipients. Lipid-based nanoparticles represent the most effective drug delivery system concerning clinical translation owing to their unique, appealing characteristics for drug delivery. To the extent of our knowledge, this is the first review to compile in vitro and in vivo evidence of encapsulating anticancer alkaloids in lipid-based nanoparticles. Alkaloids encapsulated in lipid-based nanoparticles have generally displayed enhanced in vitro cytotoxicity and an improved in vivo efficacy and toxicity profile than free alkaloids in various cancers. Encapsulated alkaloids also demonstrated the ability to overcome multidrug resistance in vitro and in vivo. These findings support the broad application of lipid-based nanoparticles to encapsulate anticancer alkaloids and facilitate their clinical translation. The review then discusses several limitations of the studies analyzed, particularly the discrepancies in reporting the pharmacokinetics, biodistribution and toxicity data. Finally, we conclude with examples of clinically successful encapsulated alkaloids that have received regulatory approval and are undergoing clinical evaluation.

Design of Lipid-Based Nanocarriers via Cation Modulation of Ethanol-Interdigitated Lipid Membranes

Short-chain alcohols (i.e., ethanol) can induce membrane interdigitation in saturated-chain phosphatidylcholines (PCs). In this process, alcohol molecules intercalate between phosphate heads, increasing lateral separation and favoring hydrophobic interactions between opposing acyl chains, which interpenetrate forming an interdigitated phase. Unraveling mechanisms underlying the interactions between ethanol and model lipid membranes has implications for cell biology, biochemistry, and for the formulation of lipid-based nanocarriers. However, investigations of ethanol-lipid membrane systems have been carried out in deionized water, which limits their applicability. Here, using a combination of small- and wide-angle X-ray scattering, small-angle neutron scattering, and all-atom molecular dynamics simulations, we analyzed the effect of varying CaCl₂ and NaCl concentrations on ethanol-induced interdigitation. We observed that while ethanol addition leads to the interdigitation of bulk phase 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) bilayers in the presence of CaCl₂ and NaCl regardless of the salt concentration, the ethanol-induced interdigitation of vesicular DPPC depends on the choice of cation and its concentration. These findings unravel a key role for cations in the ethanol-induced interdigitation of lipid membranes in either bulk phase or vesicular form.

Natural medicine combined with nanobased topical delivery systems: a new strategy to treat psoriasis

Psoriasis, an autoimmune inflammatory skin disorder, is one of the commonest immune-mediated disease conditions affecting individuals globally. At the moment, the conventional methods applied against psoriasis treatment have various drawbacks involving limited efficacy, skin irritation, immunosuppression, etc. Therefore, it is important for scientists to find a more potent and alternative drug approach towards psoriasis therapeutics. Natural medicine still remains an important source for new drug discovery due to its therapeutical significance in various drug administration routes. However, the traditional formulation of topical therapies for psoriasis is limited in efficacy, which limits the use of natural medicine. Based on the aforementioned limitations, the use of nanocarriers in preparation of these topical herbal products could be tremendously beneficial in enhancing the efficacy of topical medications. Growing pieces of evidence have proposed that the utilization of nanocarriers in transdermal preparation as a prospective technique, with regards to better potency, directs drug absorption to site of action, and minimum toxicity effect respectively. In the course of this review, we emphasized the pathological mechanism of psoriasis, natural medicine formula, active components of natural medicine, and nanopreparations used in the treatment of psoriasis.

Comparing the delivery to the hair bulb of two fluorescent molecules of distinct hydrophilicities by different nanoparticles and a serum formulation

The follicular route is an important drug penetration pathway in any topical application, either concerning dermatological and cosmetic skin treatments or any transdermal administration regimen. Efficient transport into follicles will depend on drug inherent properties but also on the chosen vehicle. The main study goal was to compare several systems for the delivery to the hair bulb of two fluorescent molecules of different water affinities: the hydrophobic Nile Red and the quite similar but hydrophilic Nile Blue. Three common nanoparticle types were compared in terms of encapsulation efficiency and stability: liposomes, ethosomes and polymeric nanoparticles. A liquid serum-like formulation was also developed, adjusting the final ethanol amount to the type of dye to be solubilized. Then, this formulation and the nanoparticle systems that successfully passed characterization and stability stages were further studied on their ability to reach the bulb. The serum formulation was able to deliver, both drug models, to deeper follicular regions than nanoparticles. Attending to the envisioned zone target of the follicle, the simplest approach proved to be the best choice from all the systems tested in this work. Nonetheless, nanocarriers and the inherent complexity of their manufacturing processes may be justified under very specific requirements.

Application of physiologically based pharmacokinetic models to promote the development of veterinary drugs with high efficacy and safety

Physiologically based pharmacokinetic (PBPK) models have become important tools for the development of novel human drugs. Food-producing animals and pets comprise an important part of human life, and the development of veterinary drugs (VDs) has greatly impacted human health. Owing to increased affordability of and demand for drug development, VD manufacturing companies should have more PBPK models required to reduce drug production costs. So far, little attention has been paid on applying PBPK models for the development of VDs. This review begins with the development processes of VDs; then summarizes case studies of PBPK models in human or VD development; and analyzes the application, potential, and advantages of PBPK in VD development, including candidate screening, formulation optimization, food effects, target-species safety, and dosing optimization. Then, the challenges of applying the PBPK model to VD development are discussed. Finally, future opportunities of PBPK models in designing dosing regimens for intracellular pathogenic infections and for efficient oral absorption of VDs are further forecasted. This review will be relevant to readers who are interested in using a PBPK model to develop new VDs.

Hexyl-aminolevulinate ethosome-mediated photodynamic therapy against acne: in vitro and in vivo analyses

Biofilm formation by Propionibacterium acnes is known to cause failure of anti-acne treatment. Conventional therapies for acne are typically inadequate. Accordingly, in this study, we evaluated the therapeutic potential of photodynamic therapy (PDT) using hexyl-aminolevulinate (HAL)-loaded ethosomes (ESs) against the biofilms of P. acnes in vitro and P. acnes-induced inflammatory acne model in vivo. The antibacterial effects of HAL ESs were evaluated using XTT colorimetric assays and scanning electron microscopic observations of morphological changes. P. acnes was intradermally injected into the ears of Sprague-Dawley rats, and the anti-inflammatory effects of HAL ESs were measured by determining changes in appearance, histology, and the antibacterial effects by P. acnes abundance in ear tissues compared with blank control ESs, HAL alone, and 5-aminolevulinic acid (ALA) alone. The highest reduction in viability in P. acnes biofilms was observed after treatment with 5 mg/mL HAL ESs. Notably, blank control ESs also showed significant inhibitory effects. Furthermore, HAL ESs had superior therapeutic effects in the rat model compared with HAL or ALA solutions. The observed therapeutic effects of HAL ESs against P. acnes biofilms and P. acnes-induced inflammation suggest that PDT with HAL-loaded ESs may have potential applications in the treatment of acne.

An evaluation of tocotrienol ethosomes for transdermal delivery using Strat-M® membrane and excised human skin

Tocotrienol (TRF) ethosomes were developed and evaluated in vitro for potential transdermal delivery against melanoma. The optimised TRF ethosomal size ranged between 64.9 ± 2.2 nm to 79.6 ± 3.9 nm and zeta potential (ZP) between -53.3 mV to -62.0 ± 2.6 mV. Characterisation of the ethosomes by ATR-FTIR indicated the successful formation of TRF-ethosomes. Scanning electron microscopy (SEM) images demonstrated the spherical shape of ethosomes, and the entrapment efficiencies of all the formulations were above 66%. In vitro permeation studies using full-thickness human skin showed that the permeation of gamma-T3 from the TRF ethosomal formulations was significantly higher (p < 0.05) than from the control. The cumulative amount of gamma-T3 permeated from TRF ethosome after 48 hours was 1.03 ± 0.24 µg cm^-2 with a flux of 0.03 ± 0.01 µg cm^-2 h^-1. Furthermore, the flux of gamma-T3 across the Strat-M ^® and the epidermal membrane was significantly higher than that across full-thickness human skin (p < 0.05). In vitro cytotoxicity studies on HaCat cells showed significantly higher cell viability than the pure drug solution (p < 0.05). The enhanced skin permeation and high cell viability associated with this formulation suggest a promising carrier for transdermal delivery.