Ultraflexible lipid vesicles allow topical absorption of cyclosporin A

Production of liposomes by microfluidics: The impact of post-manufacturing dilution on drug encapsulation and lipid loss

Microfluidic mixing is recognized as a convenient method to produce liposomes for its scalability and reproducibility. Numerous studies have described the effect of process parameters such as flow rate ratios and total flow rate on size and size distribution of vesicles. In this work, we focused our attention on the effect of flow rate ratios on the encapsulation efficiency of liposomes, as we hypothesized that different amount of residual organic solvent could affect the retention of lipophilic drug molecules within the bilayer. In a further step, we investigated how the liposomes integrity and loading were impacted by different methods of solvent removal: direct dialysis and dilution & dialysis. Liposomes were prepared by rapidly mixing an ethanolic solution of lipids and a model drug with buffer in a herringbone micromixer, employing four different flow rate ratios (FRR, 4:1, 7:3, 3:2, 1:1). Quercetin, resveratrol and ascorbyl palmitate were used as model antioxidant drugs with different lipophilicity. Data showed that liposomes produced using lower flow rate ratios (i.e., with more residual ethanol) had lower encapsulation efficiencies as well as a more prominent loss of lipids from the bilayer following purification with direct dialysis. If the amount of residual ethanol was reduced to 5% (dilution & dialysis method), the lipids and drug leakage was prevented. Such effect was correlated with the drug aggregation propensity in different ethanol/water mixtures measured by molecular dynamics simulations. Overall, these results highlight the need to tailor the purification method basing on the molecular properties of the loaded drug to ensure high encapsulation and limit the waste of material.

Recent Advancements and Trends of Topical Drug Delivery Systems in Psoriasis: A Review and Bibliometric Analysis

Psoriasis is an immune-mediated inflammatory skin disease where topical therapy is crucial. While various dosage forms have enhanced the efficacy of current treatments, their limited permeability and lack of targeted delivery to the dermis and epidermis remain challenges. We reviewed the evolution of topical therapies for psoriasis and conducted a bibliometric analysis from 1993 to 2023 using a predictive linear regression model. This included a comprehensive statistical and visual evaluation of each model's validity, literature profiles, citation patterns, and collaborations, assessing R variance and mean squared error (MSE). Furthermore, we detailed the structural features and penetration pathways of emerging drug delivery systems for topical treatment, such as lipid-based, polymer-based, metallic nanocarriers, and nanocrystals, highlighting their advantages. This systematic overview indicates that future research should focus on developing novel drug delivery systems characterized by enhanced stability, biocompatibility, and drug-carrying capacity.

Unraveling Atopic Dermatitis: Insights into Pathophysiology, Therapeutic Advances, and Future Perspectives

Atopic dermatitis (AD) is an inflammatory skin condition that frequently develops before the onset of allergic rhinitis or asthma. More than 10% of children are affected by this serious skin condition, which is painful for the sufferers. Recent research has connected the environment, genetics, the skin barrier, drugs, psychological factors, and the immune system to the onset and severity of AD. The causes and consequences of AD and its cellular and molecular origins are reviewed in this paper. The exploration of interleukins and their influence on the immunological pathway in AD has been facilitated by using relevant biomarkers in clinical trials. This approach enables the identification of novel therapeutic modalities, fostering the potential for targeted translational research within the realm of personalized medicine. This review focuses on AD's pathophysiology and the ever-changing therapeutic landscape. Beyond the plethora of biologic medications in various stages of approval or development, a range of non-biologic targeted therapies, specifically small molecules, have emerged. These include Janus kinase (JAK) inhibitors like Baricitinib, Upadacitinib, and Abrocitinib, thus expanding the spectrum of therapeutic options. This review also addresses the latest clinical efficacy data and elucidates the scientific rationale behind each targeted treatment for atopic dermatitis.

Recent Advances in Nanocarrier-based Approaches to Atopic Dermatitis and Emerging Trends in Drug Development and Design

Atopic dermatitis (AD), commonly known as Eczema, is a non-communicable skin condition that tends to become chronic. The deteriorating immunological abnormalities are marked by mild to severe erythema, severe itching, and recurrent eczematous lesions. Different pharmacological approaches are used to treat AD. The problem with commercial topical preparations lies in the limitation of skin atrophy, systemic side effects, and burning sensation that decreases patient compliance. The carrier-based system promises to eliminate these shortcomings; thus, a novel approach to treating AD is required. Liposomes, microemulsions, solid lipid nanoparticles (SLNs), nanoemulsions, etc., have been developed recently to address this ailment. Despite extensive research in the development method and various techniques, it has been challenging to demonstrate the commercial feasibility of these carrier- based systems, which illustrates a gap among the different research areas. Further, different soft wares and other tools have proliferated among biochemists as part of a cooperative approach to drug discovery. It is crucial in designing, developing, and analyzing processes in the pharmaceutical industry and is widely used to reduce costs, accelerate the development of biologically innovative active ingredients, and shorten the development time. This review sheds light on the compilation of extensive efforts to combat this disease, the product development processes, commercial products along with patents in this regard, numerous options for each step of computer-aided drug design, including in silico pharmacokinetics, pharmacodynamics, and toxicity screening or predictions that are important in finding the drug-like compounds.

Effect of invasome composition on membrane fluidity, vesicle stability and skin interactions

Invasomes have been widely exploited to enhance the percutaneous permeation of drugs. On the other hand, few studies have been dedicated to evaluating how their composition impacts the interaction with the skin, vesicle rigidity and stability, which was the focus of this investigation. Light scattering and spectroscopic techniques were considered for vesicle characterization. The addition of cholesterol (CHOL) into the phosphatidylcholine (PC) vesicles led to increased membrane rigidity (from PC:CHOL 5:0.5) and a concentration-dependent disorder effect on skin domains. Nevertheless, these vesicles were showed to be less stable. Ethanol, in turn, resulted in larger and more flexible vesicles, which can be attributed to its preferential distribution in headgroups of PC. The effect of limonene on membrane rigidity was dependent on the vesicle composition. It reduced the rigidity when few constituents were considered, but an opposite effect was observed for vesicles containing PC, CHOL, ethanol and limonene. Competitive effects of limonene and CHOL by the same domains in PC could explain these findings. Limonene was crucial to obtaining more monodisperse vesicles and it showed a synergistic action with CHOL in the disruption of lipid domains in the skin. Invasomes were more stable than liposomes. CHOL-free invasomes showed to be stable for up to 40 days at room temperature.

Emerging nanotechnology backed formulations for the management of atopic dermatitis

Atopic dermatitis is a prevalent chronic skin inflammation affecting 2.1 to 4.1% of adults globally. The complexity of its pathogenesis and the relapsing nature make it challenging to treat. Current treatments follow European Academy of Dermatology and Venerology guidelines, but advanced cases with recurring lesions lack effective therapies. To address this gap, researchers are exploring nanotechnology for targeted drug delivery. Nanoparticles offer benefits such as improved drug retention, stability, controlled release and targeted delivery through the disrupted epidermal barrier. This integrated review evaluates the current state of AD treatment and highlights the potential of novel nano-formulations as a promising approach to address the disease.

Microneedle-assisted transdermal delivery of nanoparticles: Recent insights and prospects

Transdermal delivery of drugs offers an interesting alternative for the administration of molecules that present certain troubles when delivered by the oral route. It can produce systemic effects or perform a local action when the formulation exerts an optimal controlled drug release or a targeted delivery to the specific cell type or site. It also avoids several inconveniences of the oral administration such as the hepatic first pass effect, gastric pH-induced hydrolysis, drug malabsorption because of certain diseases or surgeries, and unpleasant organoleptic properties. Nanomedicine and microneedle array patches (MAPs) are two of the trendiest delivery systems applied to transdermal research nowadays. However, the skin is a protective barrier and nanoparticles (NPs) cannot pass through the intact stratum corneum. The association of NPs and MAPs (NPs@MAPs) work synergistically, since MAPs assist NPs to bypass the outer skin layers, and NPs contribute to the system providing controlled drug release and targeted delivery. Vaccination and tailored therapies have been proposed as fields where both NPs and MAPs have great potential due to inherent characteristics. MAPs conception and easy use could allow self-administration and therefore facilitate mass vaccination campaigns in undeveloped areas with weak healthcare services. Additionally, nanomedicine is being explored as a platform to personalize therapies in such an important field as oncology. In this work we show recent insights that prove the benefits of NPs@MAPs association and analyze the prospects and the discrete interest of the industry in NPs@MAPs, evaluating different limiting steps that restricts NPs@MAPs translation to the clinical practice. This article is categorized under: Nanotechnology Approaches to Biology > NA Therapeutic Approaches and Drug Discovery > NA.

Skin drug delivery using lipid vesicles: A starting guideline for their development

Lipid vesicles can provide a cost-effective enhancement of skin drug absorption when vesicle production process is optimised. It is an important challenge to design the ideal vesicle, since their properties and features are related, as changes in one affect the others. Here, we review the main components, preparation and characterization methods commonly used, and the key properties that lead to highly efficient vesicles for transdermal drug delivery purposes. We stand by size, deformability degree and drug loading, as the most important vesicle features that determine the further transdermal drug absorption. The interest in this technology is increasing, as demonstrated by the exponential growth of publications on the topic. Although long-term preservation and scalability issues have limited the commercialization of lipid vesicle products, freeze-drying and modern escalation methods overcome these difficulties, thus predicting a higher use of these technologies in the market and clinical practice.

'Transfersome-embedded-gel' for dual-mechanistic delivery of anti-psoriatic drugs to dermal lymphocytes

AIM

Develop a platform for co-delivering clobetasol propionate (CP) and cyclosporine (CyA) to the epidermis and dermis to treat psoriasis.

METHODS

The transfersomes were prepared by thin-film hydration method. Transfersomes were characterised by dynamic light scattering and transmission electron microscope (TEM). Then, the gel stability, viscosity, pH, and spreadability were measured. Cytotoxicity of the CyA-loaded transfersome embedded in CP-dispersed gel (TEG-CyA-CP) was assessed on both human keratinocyte cell line (HaCaT) and Jurkat cells. In vitro cellular uptake and ex vivo dermal distribution was measured. The expression of inflammatory markers was assessed by reverse-transcription PCR (RT-PCR).

RESULTS

Nanoscale (<150 nm) transferosomes with high CyA encapsulation efficiency (>86%) were made. TEG-CyA-CP demonstrated higher viscosity (4808.8 ± 12.01 mPas), which may help control dual drug release. Ex vivo results showed TEG-CyA-CP ability to deliver CyA in the dermis and CP in the epidermis. RT-PCR studies showed the optimised formulation helps reduce the tumour necrosis factor (TNF-α) and interleukin-1 (IL-1) levels to relieve psoriasis symptoms.

CONCLUSION

The developed TEG-CyA-CP represents a promising fit-to-purpose delivery platform for the dual-site co-delivery of CyA and CP in treating psoriasis.

Linoleic Acid-Based Transferosomes for Topical Ocular Delivery of Cyclosporine A

Delivering high-molecular-weight hydrophobic peptides, such as cyclosporine A, across the corneal epithelium remains a challenge that is complicated by other physio-anatomical ocular structures that limit the ocular bioavailability of such peptides. Transferosomes have previously been used to improve transdermal permeability, and have the potential for improving the ocular corneal permeability of applicable drugs. In this study, transferosomes for the potential ocular delivery of cyclosporine A were investigated. Linoleic acid was evaluated for its effect on the stability of the transferosomes and was substituted for a portion of the cholesterol in the vesicles. Additionally, Span® 80 and Tween® 80 were evaluated for their effect on transferosome flexibility and toxicity to ocular cells as edge activators. Attenuated Total Reflectance–Fourier Transform Infrared spectroscopy (ATF-FTIR), differential scanning calorimetry (DSC), and dynamic light scattering (DLS) were used to evaluate the physicochemical parameters of the blank and the cyclosporine A-loaded transferosomes. Cyclosporine A release and corneal permeability were studied in vitro and in a New Zealand albino rabbit corneal model, respectively. The linoleic acid contributed to improved stability and the nano-size of the transferosomes. The Tween®-based formulation was preferred on the basis of a more favorable toxicity profile, as the difference in their corneal permeability was not significant. There was an initial burst release of cyclosporine A in the first 24 h that plateaued over one week. The Tween®-based formulation had a flux of 0.78 µg/cm2/h. The prepared transferosomes demonstrated biocompatibility in the ocular cell line, adequately encapsulated cyclosporine A, ensured the corneal permeability of the enclosed drug, and were stable over the period of investigation of 4 months at −20 °C.

Exploration of Microneedle-assisted Skin Delivery of Cyanocobalamin formulated in Ultraflexible Lipid Vesicles

Vitamin B12 (cyanocobalamin) deficiency is a widespread condition because of its different aetiologies, like malabsorption syndrome or lifestyles as strict veganism that is increasing its incidence and prevalence in developed countries. It has important haematological consequences that require pharmacological treatment. Current therapy consists of oral or parenteral supplements of cyanocobalamin; however, the oral route is discarded for malabsorption syndrome patients and the parenteral route is not well accepted generally. Topical treatments have been suggested as an alternative, but the molecular weight and hydrophilicity of cyanocobalamin limits its diffusion through the skin. Lipid vesicles can allow the transdermal absorption of molecules >500 Da. The aim of this work was to use different ultraflexible lipid vesicles (transfersomes and ethosomes) to enhance cyanocobalamin transdermal delivery. Vesicles were characterized and lyophilised for long-term stability. The ability to deliver cyanocobalamin through the skin was assessed in vitro using full-thickness porcine skin in Franz diffusion cells. As expected, the best transdermal fluxes were provided by ultraflexible vesicles, in comparison to a drug solution. Moreover, the pre-treatment of the skin with a solid microneedle array boosts the amount of drug that could potentially reach the systemic circulation.

Transdermal Delivery of Therapeutic Compounds With Nanotechnological Approaches in Psoriasis

Psoriasis is a chronic, immune-mediated skin disorder involving hyperproliferation of the keratinocytes in the epidermis. As complex as its pathophysiology, the optimal treatment for psoriasis remains unsatisfactorily addressed. Though systemic administration of biological agents has made an impressive stride in moderate-to-severe psoriasis, a considerable portion of psoriatic conditions were left unresolved, mainly due to adverse effects from systemic drug administration or insufficient drug delivery across a highly packed stratum corneum via topical therapies. Along with the advances in nanotechnologies, the incorporation of nanomaterials as topical drug carriers opens an obvious prospect for the development of antipsoriatic topicals. Hence, this review aims to distinguish the benefits and weaknesses of individual nanostructures when applied as topical antipsoriatics in preclinical psoriatic models. In view of specific features of each nanostructure, we propose that a proper combination of distinctive nanomaterials according to the physicochemical properties of loaded drugs and clinical features of psoriatic patients is becoming a promising option that potentially drives the translation of nanomaterials from bench to bedside with improved transdermal drug delivery and consequently therapeutic effects.

Improving Dermal Delivery of Rose Bengal by Deformable Lipid Nanovesicles for Topical Treatment of Melanoma

Cutaneous melanoma is one of the most aggressive and metastatic forms of skin cancer. However, current therapeutic options present several limitations, and the annual death rate due to melanoma increases every year. Dermal delivery of nanomedicines can effectively eradicate primary melanoma lesions, avoid the metastatic process, and improve survival. Rose Bengal (RB) is a sono-photosensitizer drug with intrinsic cytotoxicity toward melanoma without external stimuli but the biopharmaceutical profile limits its clinical use. Here, we propose deformable lipid nanovesicles, also known as transfersomes (TF), for the targeted dermal delivery of RB to melanoma lesions to eradicate them in the absence of external stimuli. Considering RB’s poor ability to cross the stratum corneum and its photosensitizer nature, transfersomal carriers were selected simultaneously to enhance RB penetration to the deepest skin layers and protect RB from undesired photodegradation. RB-loaded TF dispersion (RB-TF), prepared by a modified reverse-phase evaporation method, were nanosized with a ζ-potential value below −30 mV. The spectrophotometric and fluorimetric analysis revealed that RB efficiently interacted with the lipid phase. The morphological investigations (transmission electron microscopy and small-angle X-ray scattering) proved that RB intercalated within the phospholipid bilayer of TF originating unilamellar and deformable vesicles, in contrast to the rigid multilamellar unloaded ones. Such outcomes agree with the results of the in vitro permeation study, where the lack of a burst RB permeation peak for RB-TF, observed instead for the free drug, suggests that a significant amount of RB interacted with lipid nanovesicles. Also, RB-TF proved to protect RB from undesired photodegradation over 24 h of direct light exposure. The ex vivo epidermis permeation study proved that RB-TF significantly increased RB’s amount permeating the epidermis compared to the free drug (78.31 vs 38.31%). Finally, the antiproliferative assays on melanoma cells suggested that RB-TF effectively reduced cell growth compared to free RB at the concentrations tested (25 and 50 μM). RB-TF could potentially increase selectivity toward cancer cells. Considering the outcomes of the characterization and cytotoxicity studies performed on RB-TF, we conclude that RB-TF represents a valid potential alternative tool to fight against primary melanoma lesions via dermal delivery in the absence of light.

Transfersomes as alternative topical nanodosage forms for the treatment of skin disorders

Topical drug delivery is a promising approach to treat different skin disorders. However, it remains a challenge mainly due to the nature and rigidity of the nanosystems, which limit deep skin penetration, and the unsuccessful demonstration of clinical benefits; greater penetration by itself, does not ensure pharmacological success. In this context, transfersomes have appeared as promising nanosystems; deformability, their unique characteristic, allows them to pass through the epidermal microenvironment, improving the skin drug delivery. This review focuses on the comparison of transfersomes with other nanosystems (e.g., liposomes), discusses recent therapeutic applications for the topical treatment of different skin disorders and highlights the need for further studies to demonstrate significant clinical benefits of transfersomes compared with conventional therapies.

Sarsasapogenin and fluticasone combination improves DNFB induced atopic dermatitis lesions in BALB/c mice

OBJECTIVE

Atopic dermatitis (AD) is a pruritic, chronic, relapsing inflammatory skin disease. The research aims to study the effects of Sarsasapogenin and its combination with Fluticasone in 2, 4-Dinitrofluorobenzene (DNFB) induced atopic dermatitis in BALB/c mice.

MATERIAL AND METHODS

Thirty male Balb/c mice were divided into 5 groups: (i) Normal control (NC), (ii) Disease control (DNFB), (iii) Sarsasapogenin (SG) (50 µg/mice), (iv) Fluticasone (FC) (50 µg/mice), (v) Sarsasapogenin + Fluticasone (SG + FC) combination (25 µg/mice). Dermatitis was induced by repeated application of DNFB in Balb/c mice. On topical application of SG, FC, and SG + FC combination on the ear and skin lesions, body weight, ear weight, ear thickness, erythema score, spleen weight, cytokines, immunoglobulin E (IgE) levels, nitric oxide (NO) level, hematological parameters, and oxidative stress markers were evaluated. Histological analysis of the ear tissue was also done.

RESULTS

The results stated that SG and SG + FC treatment to mice considerably decrease the ear weight, ear thickness, spleen weight, serum IgE, cytokines, NO levels, and restoration of antioxidant stress markers with elevation in the hematological parameters. The observations were further confirmed by histopathological analysis of ear tissue.

CONCLUSION

These data specify that SG has been demonstrated as a probable therapy for the treatment of allergic skin diseases in combination with FC by decreasing its dose from 50 to 25 µg/mice to avoid the chronic side effects of FC. Hence, it can be concluded that SG and SG + FC combination significantly improved the AD-like symptoms in the DNFB sensitized mice through mitigating the production of proinflammatory mediators and restoration of oxidative stress markers.

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.

Recent Advancement in Topical Nanocarriers for the Treatment of Psoriasis

Psoriasis is a life-threatening autoimmune inflammatory skin disease, triggered by T lymphocyte. Recently, the drugs most commonly used for the treatment of psoriasis include methotrexate (MTX), cyclosporine (CsA), acitretin, dexamethasone, and salicylic acid. However, conventional formulations due to poor absorptive capacity, inconsistent drug release characteristics, poor capability of selective targeting, poor retention of drug molecules in target tissue, and unintended skin reactions restrict the clinical efficacy of drugs. Advances in topical nanocarriers allow the development of prominent drug delivery platforms can be employed to address the critical issues associated with conventional formulations. Advances in nanocarriers design, nano-dimensional configuration, and surface functionalization allow formulation scientists to develop formulations for a more effective treatment of psoriasis. Moreover, interventions in the size distribution, shape, agglomeration/aggregation potential, and surface chemistry are the significant aspects need to be critically evaluated for better therapeutic results. This review attempted to explore the opportunities and challenges of current revelations in the nano carrier-based topical drug delivery approach used for the treatment of psoriasis.

Cyanocobalamin Ultraflexible Lipid Vesicles: Characterization and In Vitro Evaluation of Drug-Skin Depth Profiles

Atopic dermatitis (AD) and psoriasis are the most common chronic inflammatory skin disorders, which importantly affect the quality of life of patients who suffer them. Among other causes, nitric oxide has been reported as part of the triggering factors in the pathogenesis of both conditions. Cyanocobalamin (vitamin B₁₂) has shown efficacy as a nitric oxide scavenger and some clinical trials have given positive outcomes in its use for treating skin pathologies. Passive skin diffusion is possible only for drugs with low molecular weights and intermediate lipophilicity. Unfortunately, the molecular weight and hydrophilicity of vitamin B₁₂ do not predict its effective diffusion through the skin. The aim of this work was to design new lipid vesicles to encapsulate the vitamin B₁₂ to enhance its skin penetration. Nine prototypes of vesicles were generated and characterized in terms of size, polydispersity, surface charge, drug encapsulation, flexibility, and stability with positive results. Additionally, their ability to release the drug content in a controlled manner was demonstrated. Finally, we found that these lipid vesicle formulations facilitated the penetration of cyanocobalamin to the deeper layers of the skin. The present work shows a promising system to effectively administer vitamin B₁₂ topically, which could be of interest in the treatment of skin diseases such as AD and psoriasis.

Naringenin Nano-Delivery Systems and Their Therapeutic Applications

Naringenin (NRG) is a polyphenolic phytochemical belonging to the class of flavanones and is widely distributed in citrus fruits and some other fruits such as bergamot, tomatoes, cocoa, and cherries. NRG presents several interesting pharmacological properties, such as anti-cancer, anti-oxidant, and anti-inflammatory activities. However, the therapeutic potential of NRG is hampered due to its hydrophobic nature, which leads to poor bioavailability. Here, we review a wide range of nanocarriers that have been used as delivery systems for NRG, including polymeric nanoparticles, micelles, liposomes, solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs), nanosuspensions, and nanoemulsions. These nanomedicine formulations of NRG have been applied as a potential treatment for several diseases, using a wide range of in vitro, ex vivo, and in vivo models and different routes of administration. From this review, it can be concluded that NRG is a potential therapeutic option for the treatment of various diseases such as cancer, neurological disorders, liver diseases, ocular disorders, inflammatory diseases, skin diseases, and diabetes when formulated in the appropriate nanocarriers.

Liposomes and transferosomes: a breakthrough in topical and transdermal delivery

The topical and transdermal routes of drug administration are long known to the field of pharmaceutics. These routes have been explored for the delivery of a wide range of therapeutic agents over centuries. However, the anatomy of the skin and the physicochemical properties of molecules limit their transport via these routes. To overcome these challenges, a nano-phospholipid carrier called liposome was developed in the 1960s. Liposomal delivery of drugs was reported to be limited to the upper layers of skin. This led to the development of self-regulating and self-adaptable vesicles known as transfersomes. This review critically evaluates the barriers in delivery across the skin, recent advancements in liposomes, transfersomes and their impact in the pharmaceutical field.

3,3'-Diindolylmethane alleviates acute atopic dermatitis by regulating T cell differentiation in a mouse model

Atopic dermatitis is a severe, chronic relapsing inflammatory disease of the skin with family clustering. It is characterized into acute phase, which is dominated by T helper 2-type immune responses, and chronic phase, which is dominated by T helper 1-type immune responses. Studies have shown that 3,3'-diindolylmethane not only has antitumor effects but also can relieve symptoms of inflammatory diseases by inhibiting the nuclear factor-κB signaling pathway and regulating T cell differentiation. To study the effect of 3,3'-diindolylmethane on atopic dermatitis and the underlying mechanism, a mouse model of acute atopic dermatitis was established using 2,4-dinitrofluorobenzene. After intraperitoneal injection of 3,3'-diindolylmethane, skin erythema and edema in mice were significantly alleviated. Furthermore, 3,3'-diindolylmethane reduced immune activation, probably by inhibiting the secretion of thymic stromal lymphopoietin by keratinocytes. 3,3'-Diindolylmethane also promoted the differentiation of regulatory T cells and inhibited the activation of T helper 2 and T helper 17 cells to reduce atopic dermatitis-related immune responses. However, it showed no significant effect on the differentiation of T helper 1 cells. These results indicate that 3,3'-diindolylmethane has a significant inhibitory effect on T helper 2 cells in the acute phase of atopic dermatitis. Our findings may provide not only more insights into the pathological mechanism of AD, but also a new candidate medicine for it.

Atopic Dermatitis as a Multifactorial Skin Disorder. Can the Analysis of Pathophysiological Targets Represent the Winning Therapeutic Strategy?

Atopic dermatitis (AD) is a pathological skin condition with complex aetiological mechanisms that are difficult to fully understand. Scientific evidence suggests that of all the causes, the impairment of the skin barrier and cutaneous dysbiosis together with immunological dysfunction can be considered as the two main factors involved in this pathological skin condition. The loss of the skin barrier function is often linked to dysbiosis and immunological dysfunction, with an imbalance in the ratio between the pathogen Staphylococcus aureus and/or other microorganisms residing in the skin. The bibliographic research was conducted on PubMed, using the following keywords: 'atopic dermatitis', 'bacterial therapy', 'drug delivery system' and 'alternative therapy'. The main studies concerning microbial therapy, such as the use of bacteria and/or part thereof with microbiota transplantation, and drug delivery systems to recover skin barrier function have been summarized. The studies examined show great potential in the development of effective therapeutic strategies for AD and AD-like symptoms. Despite this promise, however, future investigative efforts should focus both on the replication of some of these studies on a larger scale, with clinical and demographic characteristics that reflect the general AD population, and on the process of standardisation, in order to produce reliable data.

Trends in nanoformulations for atopic dermatitis treatment

INTRODUCTION

Immunological skin dysfunctions trigger the synthesis and release of inflammatory cytokines, which induce recurrent skin inflammation associated with chronic itching, inefficient barrier behavior, and reduced skin hydration. These features characterize a multifactorial chronic inflammatory disease atopic dermatitis (AD). AD therapy includes anti-inflammatory drugs and immunosuppressors as well as non-pharmacological alternatives such as emollients, moisturizers, and lipids (ceramides, phospholipids) for modulating the skin hydration and the barrier repair. However, these treatments are inconvenient with low drug skin penetration and insufficient maintenance on the application site.

AREAS COVERED

Nanotechnology-based therapies can be a great strategy to overcome these limitations. Considering the particular skin morphological organization, SC lipid matrix composition, and immunological functions/features related to nanocarriers, this review focuses on recent developments of nanoparticulate systems (polymeric, lipid-based, inorganic) as parent or hybrid systems including their chemical composition, physico-chemical and biopharmaceutical properties, and differential characteristics that evaluate them as new effective drug-delivery systems for AD treatment.

EXPERT OPINION

Despite the several innovative formulations, research in nanotechnology-based carriers should address specific aspects such as the use of moisturizers associated to pharmacological therapies, toxicity studies, scale-up production processes and the nanocarrier influence on immunological response. These approaches will help researchers choose the most appropriate nanocarrier system and widen nanomedicine applications and commercialization.

Freeze-Dried Softisan® 649-Based Lipid Nanoparticles for Enhanced Skin Delivery of Cyclosporine A

Inflammatory skin diseases, including psoriasis and atopic dermatitis, affect around one quarter to one third of the world population. Systemic cyclosporine A, an immunosuppressant agent, is included in the current therapeutic armamentarium of these diseases. Despite being highly effective, it is associated with several side effects, and its topical administration is limited by its high molecular weight and poor water solubility. To overcome these limitations, cyclosporine A was incorporated into solid lipid nanoparticles obtained from Softisan^® 649, a commonly used cosmetic ingredient, aiming to develop a vehicle for application to the skin. The nanoparticles presented sizes of around 200 nm, low polydispersity, negative surface charge, and stability when stored for 8 weeks at room temperature or 4 °C. An effective incorporation of 88% of cyclosporine A within the nanoparticles was observed, without affecting its morphology. After the freeze-drying process, the Softisan^® 649-based nanoparticles formed an oleogel. Skin permeation studies using pig ear as a model revealed low permeation of the applied cyclosporine A in the freeze-dried form of the nanoparticles in relation to free drug and the freshly prepared nanoparticles. About 1.0 mg of cyclosporine A was delivered to the skin with reduced transdermal permeation. These results confirm local delivery of cyclosporine A, indicating its promising topical administration.