Nanomiemgel--a novel drug delivery system for topical application--in vitro and in vivo evaluation

Polymeric Nanohydrogel in Topical Drug Delivery System

Nanohydrogels (NH) are biodegradable polymers that have been extensively studied and utilized for various biomedical applications. Drugs in a topical medication are absorbed via the skin and carried to the intended location, where they are metabolized and eliminated from the body. With a focus on their pertinent contemporary treatments, this review aims to give a complete overview of recent advances in the creation and application of polymer NH in biomedicine. We will explore the key features that have driven advances in nanotechnology and discuss the significance of nanohydrogel-based formulations as vehicles for delivering therapeutic agents topically. The review will also cover the latest findings and references from the literature to support the advancements in nanotechnological technology related to the preparation and application of NH. In addition, we will also discuss the unique properties and potential applications of NH as drug delivery systems (DDS) for skin applications, underscoring their potential for effective topical therapeutic delivery. The challenge lies in efficiently delivering drugs through the skin's barrier to specific areas with high control. Environmentally sensitive systems, like polymer-based NH, show promise in treating dermatological conditions. Polymers are pivotal in developing these drug delivery systems, with NH offering advantages such as versatile drug loading, controlled release, and enhanced skin penetration.

Qingre Lishi Decoction ameliorates imiquimod-induced psoriasis-like skin lesions in SKH-1 mice by regulating the Treg-DC-Th17 axis and inhibiting MAPK-mediated DC maturation

ETHNOPHARMACOLOGICAL RELEVANCE

Psoriasis, an immune system disorder, is a chronic relapsing disease that cannot be cured. Chinese herbal medicine is gradually considered a promising alternative treatment for psoriasis due to its multiple effects, ability to target multiple pathways and lower toxicity. Qingre Lishi Decoction (QRLSD) is effective in clinical treatment. However, its related molecular mechanism remains to be elucidated.

AIM OF THE STUDY

The purpose of this research was to investigate the therapeutic impacts of Qingre Lishi Decoction on the murine model of psoriasis-like skin lesions induced by imiquimod and to reveal the underlying mechanisms.

MATERIALS AND METHODS

First, QRLSD was orally administered to evaluate its efficacy in an imiquimod (IMQ)-induced psoriasis mouse model. Further, UPLC-Q-TOF/MS was used to analyze the compounds of QRLSD. To investigate the mechanism and main targets of QRLSD for treating psoriasis, network pharmacology and molecular docking methods were utilized. Finally, To further confirm the anti-psoriasis target, dendritic cells derived from bone marrow (BMDCs) were cultured in vitro.

RESULTS

In vivo experiments found that QRLSD could regulate the ratio of dendritic cells, Treg cells, and Th17 cells in the body and inhibit inflammation and keratinocyte proliferation in psoriasis-like skin lesions. Further analysis showed that the p38-MAPK pathway is one of its main signaling pathways. In vitro experiments confirmed that QRLSD suppressed the maturation and activation of BMDCs via the p38-MAPK signaling pathway.

CONCLUSIONS

This study suggests that Qingre Lishi Decoction has the promise to be an effective formula for treating psoriasis through the p38-MAPK pathway, which can help break through the current limitations of psoriasis in clinical treatment.

Topical Delivery of Terbinafine HCL Using Nanogels: A New Approach to Superficial Fungal Infection Treatment

This study investigated pH-responsive Terbinafine HCL (TBH)-loaded nanogels as a new approach to treating superficial fungal infections. Acrylic acid (AA) is a synthetic monomer that was crosslinked with a natural polymer (gelatin) using a free radical polymerization technique to fabricate gelatin-g-poly-(acrylic acid) nanogels. Ammonium persulphate (APS) and N, N'-methylene bisacrylamide (MBA) were used as the initiator and crosslinker, respectively. Developed gelatin-g-poly-(acrylic acid) nanogels were evaluated for the swelling study (pH 1.2, 5, 7.4), DEE, particle size, FTIR, thermal stability (TGA, DSC), XRD, SEM, DEE, and in vitro drug release study to obtain optimized nanogels. Optimized nanogels were incorporated into 1% HPMC gel and then evaluated in comparison with Lamisil cream 1% for TBH stratum corneum retention, skin irritation, and in vitro and in vivo antifungal activity studies. Optimized nanogels (AAG 7) demonstrated a 255 nm particle size, 82.37% DEE, pH-dependent swelling, 92.15% of drug release (pH) 7.4 within 12 h, and a larger zone of inhibition compared to Lamisil cream. HPMC-loaded nanogels significantly improved the TBH skin retention percentage, as revealed by an ex vivo skin retention study, indicating the usefulness of nanogels for topical use. In vivo studies conducted on animal models infected with a fungal infection have further confirmed the effectiveness of nanogels compared with the Lamisil cream. Hence, Gelatin-g-poly-(acrylic acid) nanogels carrying poorly soluble TBH can be a promising approach for treating superficial fungal infections.

Statistically Optimized Tacrolimus and Thymoquinone Co-Loaded Nanostructured Lipid Carriers Gel for Improved Topical Treatment of Psoriasis

The aim of this investigation was to develop and analyze a tacrolimus and thymoquinone co-loaded nanostructured lipid carriers (TAC-THQ-NLCs)-based nanogel as a new combinatorial approach for the treatment of psoriasis. The NLCs were formulated by an emulsification-solvent-evaporation technique using glyceryl monostearate, Capryol 90 (oil), and a mixture of Tween 80 and Span 20 as a solid lipid, liquid lipid, and surfactant, respectively. Their combination was optimized using a three-factor and three-level Box-Behnken design (3³-BBD). The optimized TAC-THQ-NLCs were observed to be smooth and spherical with a particle size of 144.95 ± 2.80 nm, a polydispersity index of 0.160 ± 0.021, a zeta potential of -29.47 ± 1.9 mV, and an entrapment efficiency of >70% for both drugs. DSC and PXRD studies demonstrated the amorphous state of TAC and THQ in the lipid matrix of the NLCs. An FTIR analysis demonstrated the excellent compatibility of the drugs with the excipients without interactions. The TAC-THQ-NLC-based nanogel (abbreviated as TAC-THQ-NG) exhibited a good texture profile and good spreadability. The in vitro release study demonstrated a sustained drug release for 24 h from the TAC-THQ-NG that followed the Korsmeyer-Peppas kinetic model with a Fickian diffusion mechanism. Moreover, the TAC-THQ-NG revealed significantly higher dose-dependent toxicity against an HaCaT cell line compared to a TAC-THQ suspension gel (abbreviated as TAC-THQ-SG). Furthermore, the developed formulations demonstrated antioxidant activity comparable to free THQ. Confocal microscopy revealed improved permeation depth of the dye-loaded nanogel in the skin compared to the suspension gel. Based on these findings, it was concluded that TAC-THQ-NG is a promising combinatorial treatment approach for psoriasis.

An Overview of Nanoemulgels for Bioavailability Enhancement in Inflammatory Conditions via Topical Delivery

The anti-inflammatory drugs that are generally available possess the disadvantage of hydrophobicity, which leads to poor permeability and erratic bioavailability. Nanoemulgels (NEGs) are novel drug delivery systems that aim to improve the solubility and permeability of drugs across the biological membrane. The nano-sized droplets in the nanoemulsion enhance the permeation of the formulation, along with surfactants and co-surfactants that act as permeation enhancers and can further improve permeability. The hydrogel component of NEG helps to increase the viscosity and spreadability of the formulation, making it ideal for topical application. Moreover, oils that have anti-inflammatory properties, such as eucalyptus oil, emu oil and clove oil, are used as oil phases in the preparation of the nanoemulsion, which shows a synergistic effect with active moiety and enhances its overall therapeutic profile. This leads to the creation of hydrophobic drugs that possess enhanced pharmacokinetic and pharmacodynamic properties, and simultaneously avoid systemic side effects in individuals with external inflammatory disorders. The nanoemulsion's effective spreadability, ease of application, non-invasive administration, and subsequent ability to achieve patient compliance make it more suitable for topical application in the combat of many inflammatory disorders, such as dermatitis, psoriasis, rheumatoid arthritis, osteoarthritis and so on. Although the large-scale practical application of NEG is limited due to problems regarding its scalability and thermodynamic instability, which arise from the use of high-energy approaches during the production of the nanoemulsion, these can be resolved by the advancement of an alternative nanoemulsification technique. Considering the potential advantages and long-term benefits of NEGs, the authors of this paper have compiled a review that elaborates the potential significance of utilizing nanoemulgels in a topical delivery system for anti-inflammatory drugs.

Can Essential Oils/Botanical Agents Smart-Nanoformulations Be the Winning Cards against Psoriasis?

Although psoriasis remains one of the most devastating inflammatory disorders due to its huge negative impact on patients’ quality of life, new “green” treatment approaches still need to be fully explored. The purpose of this review article is to focus on the utilization of different essential oils and active constituents of herbal botanical origin for the treatment of psoriasis that proved efficacious via both in vitro and in vivo models. The applications of nanotechnology-based formulations which displayed great potential in augmenting the permeation and delivery of these agents is also addressed. Numerous studies have been found which assessed the potential activity of natural botanical agents to overcome psoriasis. Nano-architecture delivery is applied in order to maximize the benefits of their activity, improve properties, and increase patient compliance. This field of natural innovative formulations can be a promising tool to optimize remediation of psoriasis while minimizing adverse effects.

Nanoemulgel: A Novel Nano Carrier as a Tool for Topical Drug Delivery

Nano-emulgel is an emerging drug delivery system intended to enhance the therapeutic profile of lipophilic drugs. Lipophilic formulations have a variety of limitations, which includes poor solubility, unpredictable absorption, and low oral bioavailability. Nano-emulgel, an amalgamated preparation of different systems aims to deal with these limitations. The novel system prepared by the incorporation of nano-emulsion into gel improves stability and enables drug delivery for both immediate and controlled release. The focus on nano-emulgel has also increased due to its ability to achieve targeted delivery, ease of application, absence of gastrointestinal degradation or the first pass metabolism, and safety profile. This review focuses on the formulation components of nano-emulgel for topical drug delivery, pharmacokinetics and safety profiles.

Nanoparticles for Topical Application in the Treatment of Skin Dysfunctions-An Overview of Dermo-Cosmetic and Dermatological Products

Nanomaterials (NM) arouse interest in various fields of science and industry due to their composition-tunable properties and the ease of modification. They appear currently as components of many consumer products such as sunscreen, dressings, sports clothes, surface-cleaning agents, computer devices, paints, as well as pharmaceutical and cosmetics formulations. The use of NPs in products for topical applications improves the permeation/penetration of the bioactive compounds into deeper layers of the skin, providing a depot effect with sustained drug release and specific cellular and subcellular targeting. Nanocarriers provide advances in dermatology and systemic treatments. Examples are a non-invasive method of vaccination, advanced diagnostic techniques, and transdermal drug delivery. The mechanism of action of NPs, efficiency of skin penetration, and potential threat to human health are still open and not fully explained. This review gives a brief outline of the latest nanotechnology achievements in products used in topical applications to prevent and treat skin diseases. We highlighted aspects such as the penetration of NPs through the skin (influence of physical-chemical properties of NPs, the experimental models for skin penetration, methods applied to improve the penetration of NPs through the skin, and methods applied to investigate the skin penetration by NPs). The review summarizes various therapies using NPs to diagnose and treat skin diseases (melanoma, acne, alopecia, vitiligo, psoriasis) and anti-aging and UV-protectant nano-cosmetics.

Machine Learning Models Identify New Inhibitors for Human OATP1B1

The uptake transporter OATP1B1 (SLC01B1) is largely localized to the sinusoidal membrane of hepatocytes and is a known victim of unwanted drug-drug interactions. Computational models are useful for identifying potential substrates and/or inhibitors of clinically relevant transporters. Our goal was to generate OATP1B1 in vitro inhibition data for [3H] estrone-3-sulfate (E3S) transport in CHO cells and use it to build machine learning models to facilitate a comparison of seven different classification models (Deep learning, Adaboosted decision trees, Bernoulli naïve bayes, k-nearest neighbors (knn), random forest, support vector classifier (SVC), logistic regression (lreg), and XGBoost (xgb)] using ECFP6 fingerprints to perform 5-fold, nested cross validation. In addition, we compared models using 3D pharmacophores, simple chemical descriptors alone or plus ECFP6, as well as ECFP4 and ECFP8 fingerprints. Several machine learning algorithms (SVC, lreg, xgb, and knn) had excellent nested cross validation statistics, particularly for accuracy, AUC, and specificity. An external test set containing 207 unique compounds not in the training set demonstrated that at every threshold SVC outperformed the other algorithms based on a rank normalized score. A prospective validation test set was chosen using prediction scores from the SVC models with ECFP fingerprints and were tested in vitro with 15 of 19 compounds (84% accuracy) predicted as active (≥20% inhibition) showed inhibition. Of these compounds, six (abamectin, asiaticoside, berbamine, doramectin, mobocertinib, and umbralisib) appear to be novel inhibitors of OATP1B1 not previously reported. These validated machine learning models can now be used to make predictions for drug-drug interactions for human OATP1B1 alongside other machine learning models for important drug transporters in our MegaTrans software.

Enhancement of transdermal permeation of cannabinoids and their pharmacodynamic evaluation in rats

The objective of the present study was to enhance the transdermal permeation of cannabinoids: cannabidiol (CBD), cannabigerol (CBG) and tetrahydrocannabivarin (THCV) using chemical permeation enhancer approach and evaluate them for their anti-inflammatory effect in vivo in a paw edema model in rats. Cannabinoids gel formulations were developed using FDA approved inactive ingredients: lactic acid (LA), polyethylene glycol-400 (PEG-400), N-methyl-2 pyrrolidone (NMP), dimethyl sulfoxide (DMSO). In vitro skin permeation testing (IVPT) showed flux of ∼ 13.25 μg/cm²/h for CBD, ∼9.38 μg/cm²/h for CBG and ∼ 51.74 μg/cm²/h for THCV. Additionally, IVPT study showed cumulative drug permeation of 610.96 ± 88.92 μg/cm², 432.09 ± 35.59 μg/cm² and 2384.44 ± 42.22 μg/cm² from CBD, CBG and THCV gel formulations respectively. Further, effect of excipients on cannabinoid permeation showed that, formulation containing lactic acid, NMP and DMSO showed significantly (p < 0.0001) enhanced flux of cannabinoids as compared to formulation without LA, NMP and DMSO. In vivo studies showed that paw edema was significantly (p < 0.0001) reduced in the groups containing CBD, CBG, THCV as compared to control and placebo formulation. In conclusion, flux of CBD, CBG and THCV was significantly enhanced using chemical permeation enhancers approach which helped in reducing rat paw edema.

A combination of linalool and linalyl acetate synergistically alleviates imiquimod-induced psoriasis-like skin inflammation in BALB/c mice

Introduction: Psoriasis is a chronic inflammatory skin disorder characterized by keratinocyte hyperproliferation and differentiation with increased immune cell infiltration. The anti-psoriatic effect of lavender oil has been reported. However, its phytoconstituents, linalool (L) and linalyl acetate (LA), showed a distinctive affinity with psoriasis targets.

Objectives: This investigation was aimed to determine the combined effect of L and LA in ameliorating psoriasis-like skin inflammation and its safety in long-term topical uses.

Methods: The combined effect of L and LA was compared with their individual effects. The anti-psoriatic activity was performed using imiquimod (IMQ)-induced psoriasis in BALB/c mice and evaluated to reduce PASI and CosCam scores and Th-1 and Th-17 cell-specific cytokine levels. The acute and repeated dose dermal toxicities were investigated as per the OECD guidelines.

Results: L and LA combination (LLA) in the 1:1 w/w ratio at 2% concentration showed a synergistic effect. The combination showed 76.31% and 71.29% recovery in PASI and CosCam Scores; however, L2% and LA2% showed 64.28% and 47.61% recovery in PASI and 64.75 and 56.76% recovery in CosCam scores, respectively. It showed >90% and >100% recovery in Th-17 and Th-1 cell-specific cytokines, respectively, and restored epidermal hyperplasia and parakeratosis toward normal compared with psoriatic mice. A marked reduction in NF-κB, cck6, and the IL-17 expression was also observed in the LLA-treated group. This combination was safe in a therapeutically effective dose for 28 days as no significant changes were observed in organ and body weights, liver and kidney parameters, and differential leukocyte counts.

Conclusion: This study proves the synergy between L and LA in a 1:1 w/w ratio at 2% in the treatment of psoriasis-like skin inflammation and provides strong scientific evidence for its safe topical use.

Recent advances in pain management based on nanoparticle technologies

BACKGROUND

Pain is a vital sense that indicates the risk of injury at a particular body part. Successful control of pain is the principal aspect in medical treatment. In recent years, the advances of nanotechnology in pain management have been remarkable. In this review, we focus on literature and published data that reveal various applications of nanotechnology in acute and chronic pain management.

METHODS

The presented content is based on information collected through pain management publications (227 articles up to April 2021) provided by Web of Science, PubMed, Scopus and Google Scholar services.

RESULTS

A comprehensive study of the articles revealed that nanotechnology-based drug delivery has provided acceptable results in pain control, limiting the side effects and increasing the efficacy of analgesic drugs. Besides the ability of nanotechnology to deliver drugs, sophisticated nanosystems have been designed to enhance imaging and diagnostics, which help in rapid diagnosis of diseases and have a significant impact on controlling pain. Furthermore, with the development of various tools, nanotechnology can accurately measure pain and use these measurements to display the efficiency of different interventions.

CONCLUSIONS

Nanotechnology has started a new era in the pain management and many promising results have been achieved in this regard. Nevertheless, there is still no substantial and adequate act of nanotechnology in this field. Therefore, efforts should be directed to broad investigations.

Nanoemulsions: A Review on the Conceptualization of Treatment for Psoriasis Using a 'Green' Surfactant with Low-Energy Emulsification Method

Psoriasis is a skin disease that is not lethal and does not spread through bodily contact. However, this seemingly harmless condition can lead to a loss of confidence and social stigmatization due to a persons' flawed appearance. The conventional methods of psoriasis treatment include taking in systemic drugs to inhibit immunoresponses within the body or applying topical drugs onto the surface of the skin to inhibit cell proliferation. Topical methods are favored as they pose lesser side effects compared to the systemic methods. However, the side effects from systemic drugs and low bioavailability of topical drugs are the limitations to the treatment. The use of nanotechnology in this field has enhanced drug loading capacity and reduced dosage size. In this review, biosurfactants were introduced as a 'greener' alternative to their synthetic counterparts. Glycolipid biosurfactants are specifically suited for anti-psoriatic application due to their characteristic skin-enhancing qualities. The selection of a suitable oil phase can also contribute to the anti-psoriatic effect as some oils have skin-healing properties. The review covers the pathogenic pathway of psoriasis, conventional treatments, and prospective ingredients to be used as components in the nanoemulsion formulation. Furthermore, an insight into the state-of-the-art methods used in formulating nanoemulsions and their progression to low-energy methods are also elaborated in detail.

Formulation development, optimization, and in vitro assessment of thermoresponsive ophthalmic pluronic F127-chitosan in situ tacrolimus gel

To overcome problems associated with topical delivery of tacrolimus (TCS), a thermoresponsive in situ gel system containing pluronic F127 (PL), and chitosan (CS) was developed, to enhance the precorneal retention, and to sustain the release of the drug. The PL-CS in situ gel was optimized using a 2-factor-3-level central composite experimental design by selecting the concentration of PL and CS as independent variables while gelation time, gelation temperature, and spreadability as dependent variables. The optimized formulation was developed using 22.5 g PL and 0.3 g CS, gels at 33.6 °C, in 22.93 s, and showed the spreadability of 6.2 cm. In vitro studies conducted for the optimized gel revealed the sustained release of TCS (81.73% in 4 h) and improved corneal permeation (74.13% in 4 h), compared with TCS solution. The mechanism of release of TCS followed the Higuchi model with Fickian diffusion transport. Further, histopathology and HET-CAM studies revealed that the developed gel was non-irritating and safe for ocular administration.

Rediscovering Tocophersolan: A Renaissance for Nano-Based Drug Delivery and Nanotheranostic Applications

A unique and pleiotropic polymer, d-alpha-tocopheryl polyethylene glycol succinate (Tocophersolan), is a polymeric, synthetic version of vitamin E. Tocophersolan has attracted enormous attention as a versatile excipient in different biomedical applications including drug delivery systems and nutraceuticals. The multiple inherent properties of Tocophersolan allow it to play flexible roles in drug delivery system design, including excipients with outstanding biocompatibility, solubilizer with the ability to promote drug dissolution, drug permeation enhancer, P-glycoprotein inhibitor, and anticancer compound. For these reasons, Tocophersolan has been widely used for improving the bioavailability of numerous pharmaceutical active ingredients. Tocophersolan has been approved by stringent regulatory authorities (such as the US FDA, EMA, and PMDA) as a safe pharmaceutical excipient. In this review, the current advances in nano-based delivery systems consisting of Tocophersolan, with possibilities for futuristic applications in drug delivery, gene therapy, and nanotheranostics, were systematically curated.

Nanoemulgel for Improved Topical Delivery of Desonide: Formulation Design and Characterization

This research aimed to develop a novel drug delivery system to improve treatment of skin disorders. The system is comprised of a Carbopol 980-based nanoemulgel (NE-gel) containing a desonide (DES; 0.05%, w/w) nanoemulsion (NE), which has a small particle size, high encapsulation efficiency, good thermodynamic stability, good permeation ability, and high skin retention. DES-loaded NE (DES-NE) was prepared by high-pressure homogenization. The developed formulation was characterized by differential scanning calorimetry (DSC), X-ray diffraction, drug release, skin permeation, and drug retention. DES in vitro release and skin permeation studies with different formulations of artificial membrane and rat abdominal skin were performed with the Franz diffusion cell system. Confocal laser scanning microscopy (CLSM) was used to detect the localization and permeation pathways of drugs in the skin. Compared with commercially available gel (CA-gel) and NE, the NE-gel release process conformed to the Higuchi release model (R² = 0.9813). NE-gel prolonged the drug release time and allowed for reduced administration dose and frequency. The unit cumulative permeation of NE and NE-gel through the skin for 12 h was 63.13 ± 2.78 and 42.53 ± 2.06 μg/cm², respectively, values significantly higher (p < 0.01) than that of the CA-gel (30.65 ± 1.25 μg/cm²) and CA-cream (15.21 ± 0.97 μg/cm²). The DES-NE and DES NE-gel skin drug retention was significantly higher than commercially available formulations (p < 0.01). Hence, the prepared NE-gel is a potential vehicle for improved topical DES delivery for better treatment of skin disorders.

Investigating the Potential of Transdermal Delivery of Avanafil Using Vitamin E-TPGS Based Mixed Micelles Loaded Films

To avoid the first-pass metabolism of avanafil (AVA) and its altered absorption in the presence of food after oral administration, this study aimed to investigate the potential of TPGS-based mixed micelle (MM)-loaded film for transdermal delivery and the enhancement of bioavailability. A Box-Behnken design was employed to optimize the permeation behavior of AVA from the transdermal film across the skin. The variables were the hydrophile-lipophile balance (HLB) of the surfactant (X₁), the concentration of mixed micelles (MMs) in the film (X₂), and the concentration of the permeation enhancer (X₃). The initial permeation of AVA after 1 h (Y₁), and the cumulative permeation of AVA after 24 h (Y₂) were the dependent variables. Ex vivo studies were carried out on freshly isolated rat skin to investigate the drug's permeation potential and results were visualized using a fluorescence laser microscope. Moreover, the pharmacokinetic behavior after a single application on male Wistar rats, in comparison with films loaded with raw AVA, was evaluated. The results showed that the optimum factor levels were 9.4% for the HLB of the surfactant used, and 5.12% MMs and 2.99% penetration enhancer in the film. Imaging with a fluorescence laser microscope indicated the ability of the optimized film to deliver the payload to deeper skin layers. Furthermore, optimized AVA-loaded TPGS-micelles film showed a significant increase (p < 0.05) in the C_max of AVA and the area under the AVA plasma curve (approximately three-fold). The optimized AVA-loaded TPGS-MM film thus represents a successful delivery system for enhancing the bioavailability of AVA.

Treatment Strategies Against Psoriasis: Principle, Perspectives and Practices

BACKGROUND

Psoriasis is a genetically predisposed autoimmune disease mediated by cytokines released by the activated immune cells. It manifests inflammatory, scaly red or white silvery flaky skin which may be a fluid-filled lesion with soreness and itchiness. The prevalence rate of psoriasis is increasing day by day. Despite having such a high prevalence rate, the treatment of psoriasis is still limited. Hence, there is a need to rethink the various treatment strategies available in the allopathic as well as in the alternative systems of medicine.

METHODS

Various bibliographic databases of previously published peer-reviewed research papers were explored and systematic data culminated in terms of various treatment strategies used for the management of psoriasis. The prime focus is given towards modern as well as alternative systems of medicine such as phototherapy, a combination of phototherapy with pharmacotherapy such as Ayurveda, Yoga and naturopathy, Unani, Siddha, and Homeopathy to treat psoriasis.

RESULTS

A comprehensive review of 161 papers, including both research and review articles, was carried out to make the article readily understandable. The pathogenesis including inflammatory mediators and type of psoriasis is discussed before the treatment strategies to understand the pathophysiology of the disease. The uniqueness, procedure, advantages, and limitations of conventional, advanced, and traditional systems of medicine to treat psoriasis are discussed in detail. Emphasis has also been given towards marine sources such as fish oil, marine sponges, and algae.

CONCLUSION

Although there are many modern and alternative treatment strategies available to treat psoriasis, none of them have been proven to provide complete relief to patients. Moreover, they are associated with certain side effects. In order to overcome them, novel drug delivery systems have been utilized and found effective; however, their stability and safety become the major impediments towards their successful positioning. Traditional and alternative treatment strategies have found to be safe and effective but their use is localized to certain areas. In a nutshell, to achieve successful treatment of psoriasis, there is a need to focus on the development of stable and non-toxic novel drug delivery systems or the promotion of traditional systems to treat psoriasis.

Nanomaterial Lipid-Based Carrier for Non-Invasive Capsaicin Delivery; Manufacturing Scale-Up and Human Irritation Assessment

Capsaicin is an active compound in chili peppers (Capsicum chinense) that has been approved for chronic pain treatment. The topical application of high-strength capsaicin has been proven to reduce pain; however, skin irritation is a major drawback. The aim of this study was to investigate an appropriate and scalable technique for preparing nanostructured lipid carriers (NLCs) containing 0.25% capsaicin from capsicum oleoresin (NLC_C) and to evaluate the irritation of human skin by chili-extract-loaded NLCs incorporated in a gel formulation (Gel NLC_C). High-shear homogenization with high intensity (10,000 rpm) was selected to create uniform nanoparticles with a size range from 106 to 156 nm. Both the NLC_C and Gel NLC_C formulations expressed greater physical and chemical stabilities than the free chili formulation. Release and porcine biopsy studies revealed the sustained drug release and significant permeation of the NLCs through the outer skin layer, distributing in the dermis better than the free compounds. Finally, the alleviation of irritation and the decrease in uncomfortable feelings following the application of the Gel NLC_C formulation were compared to the effects from a chili gel and a commercial product in thirty healthy volunteers. The chili-extract-loaded NLCs were shown to be applicable for the transdermal delivery of capsaicin whilst minimizing skin irritation, the major noncompliance cause of patients.

Anti-psoriatic effect of Lavandula angustifolia essential oil and its major components linalool and linalyl acetate

ETHNO-PHARMACOLOGICAL RELEVANCE

Lavender oil (LO) is an aromatic/essential oil extracted from Lavandula angustifolia and traditionally used as an aromatherapy massage oil due to its anti-inflammatory and wound healing property and also for providing the relief in other skin conditions such as psoriasis, dermatitis and eczema. However, LO has not been evaluated scientifically for psoriasis like skin inflammation.

AIM OF THE STUDY

This study was aimed to investigate the LO and its major components linalool (L) and linalyl acetate (LA) against psoriasis like skin inflammation.

MATERIALS AND METHODS

Anti-psoriatic activity was done using Imiquimod (IMQ) induced psoriasis like skin inflammation in BALB/c mice. Assessment of anti-psoriatic effect of LO, L and LA was done on the basis of change in ear thickness, psoriasis area severity index (PASI) scoring at alternative day, CosCam scoring using skin analyzer equipped with SkinSys software, biochemical, immunohistochemical and histological investigations. Level of effectiveness against psoriasis was investigated by percent reduction in PASI scores, CosCam scores and level of Th-1 and Th-17 cell expressing cytokines, as compared to the diseased mice.

RESULTS

Topical application of LO 10% showed 73.67% recovery in PASI and 87% in Th-17 cell-specific cytokines towards normal as compared to disease group. L and LA were identified as the major components of LO and favoured ligands for selected psoriasis targets. At 2% topical dose, L and LA showed 64% and 47.61% recovery in PASI scores, respectively. Both, L and LA showed significant recovery in Th-1 specific TNF-α and IL-1β however, only L showed significant recovery of Th-17 cytokines (IL-17 and IL-22). In contrast to LA (which restored granulosis), L restored epidermal hyperplasia and parakeratosis toward the normal condition. On the other hand, L also reduced the expression of NF-κβ, ccr6 and IL-17, while LA reduced the expression of NF-κβ only. At 10% topical dose, LO was observed to be slight irritant while at 2% topical dose, L and LA were found non-irritant to the skin.

CONCLUSION

This study proves the effectiveness of LO and its major phytoconstituents linalool and linalyl acetate against IMQ induced psoriasis like skin inflammation and provides the scientific evidence for topical use of lavender oil.

Improved Transmucosal Delivery of Glimepiride via Unidirectional Release Buccal Film Loaded With Vitamin E TPGS-Based Nanocarrier

Glimepiride (GMD) is a hypoglycemic agent that has variation in bioavailability for its unexpected absorption. Glimepiride was formulated in a buccal film loaded with a nanobased formulation to enhance its absorption via buccal mucosa. Nanostructured lipid carriers (NLCs) and d-α-tocopherol polyethylene glycol 1000 succinate-based micelles enhance GMD solubility and improve its permeation through the buccal mucosa. The formulation variables were optimized using a Box-Behnken design. These factors, such as the percent of micelles relative to NLC (X₁), the percent of Carbopol (X₂), and the percent of permeation enhancer (X₃), were investigated for their effect on the initial release (Y₁) and the cumulative release after 6 hours (Y₂). The optimum levels for X₁, X₂, and X₃ were 100%, 0.05%, and 1.8%, respectively. The optimized formulation revealed that the permeation of GMD from the film was in favor of micelles. This optimized film was then coated with ethyl cellulose to direct the release only through the buccal mucosa. The optimized unidirectional GMD transmucosal film showed a release of 93.9% of GMD content at 6 hours compared to 60.41% of GMD release from the raw GMD film. This finding confirmed the suitability of transmucosal delivery of GMD via the buccal mucosa.

Evolution of Nanotechnology in Delivering Drugs to Eyes, Skin and Wounds via Topical Route

The topical route is the most preferred one for administering drugs to eyes, skin and wounds for reaching enhanced efficacy and to improve patient compliance. Topical administration of drugs via conventional dosage forms such as solutions, creams and so forth to the eyes is associated with very low bioavailability (less than 5%) and hence, we cannot rely on these for delivering drugs to eyes more efficiently. An intravitreal injection is another popular drug delivery regime but is associated with complications like intravitreal hemorrhage, retinal detachment, endophthalmitis, and cataracts. The skin has a complex structure that serves as numerous physiological barriers to the entry of exogenous substances. Drug localization is an important aspect of some dermal diseases and requires directed delivery of the active substance to the diseased cells, which is challenging with current approaches. Existing therapies used for wound healing are costly, and they involve long-lasting treatments with 70% chance of recurrence of ulcers. Nanotechnology is a novel and highly potential technology for designing formulations that would improve the efficiency of delivering drugs via the topical route. This review involves a discussion about how nanotechnology-driven drug delivery systems have evolved, and their potential in overcoming the natural barriers for delivering drugs to eyes, skin and wounds.

Lipid Vesicles and Nanoparticles for Non-invasive Topical and Transdermal Drug Delivery

The delivery of drugs, via different layers of skin, is challenging because it acts as a natural barrier and exerts hindrance against molecules to permeate into or through it. To overcome such obstacles, different noninvasive methods, like vehicle-drug interaction, modifications of the horny layer and nanoparticles have been suggested. The aim of the present review is to highlight some of the non-invasive methods for topical, diadermal and transdermal delivery of drugs. Special emphasis has been made on the information available in numerous research articles that put efforts in overcoming obstacles associated with barrier functions imposed by various layers of skin. Advances have been made in improving patient compliance that tends to avoid hitches involved in oral administration. Of particular interest is the use of lipid-based vesicles and nanoparticles for dermatological applications. These particulate systems can effectively interact and penetrate into the stratum corneum via lipid exchange and get distributed in epidermis and dermis. They also have the tendency to exert a systemic effect by facilitating the absorption of an active moiety into general circulation.

Magnesium oil enriched transdermal nanogel of methotrexate for improved arthritic joint mobility, repair, and reduced inflammation

Aim: Methotrexate (Mtx) is prescribed to reduce pain and inflammation in arthritis patients; however, improved repair and mobility of joints still are the major concerns. Magnesium oil (MO) improves joint mobility and repair; therefore, MO-assisted transdermal delivery of Mtx was aimed.Methods: MO integrated Mtx nanoemulsion (Mtx-MONE) was prepared with uniform size (175 ± 35.4 nm), pH (6.15 ± 0.3) near to skin pH, and high entrapment efficiency (65 ± 8.6%). Mtx-MONE was transformed to nanogel (Mtx-MONEG) with semisolid consistency (43,408 ± 77.72 cP) and good spreadability (3.63 ± 0.033 mJ).Results: Mtx-MONEG showed significant reduction in oedema, arthritic scores, level of inflammatory cytokines, and improved walking as compared to diseased control. MO offered additional improvements in joints, mobility, and repair.Conclusion: Transdermal delivery of Mtx has been successfully achieved by Mtx-MONEG. Tremendous recovery from inflammation, improved joints mobility and repair, and reduced pain strongly support the use of MO as an adjutant of Mtx for improved transdermal application.

Nanodermatology-based solutions for psoriasis: State-of-the art and future prospects

Nanodermatology is an emerging, multidisciplinary science, arising from the convergence of nanotechnology, pharmacology, physics/biophysics, chemistry/biochemistry, chemical engineering, material science, and clinical medicine. Nanodermatology deals with (a) skin biology, anatomy, and physiology at the nanoscale ("skin nanobiology"), (b) diagnosis performed by means of novel diagnostic devices, assisted by nanobiotechnologies ("nanodiagnosis"), and (c) treatment through innovative therapeutic agents, including phototherapy ("photonanotherapy"/"photonanodermatology") and systemic/topical drug administration ("nanotherapy") at the nanoscale, and drug delivery-such as transdermal or dermal drug delivery (TDDD/DDD)-enhanced and improved by nanostructures and nanodrugs ("nanodrug delivery"). Nanodermatology, as a super-specialized branch of dermatology, is a quite recent specialty: the "Nanodermatology Society" founded by the eminent dermatologist Dr. Adnan Nasir, was established in 2010, with the aim of bringing together different stakeholders, including dermatologists, nanotechnology scientists, policy-makers and regulators, as well as students and medical residents. Psoriasis has a prevalence of 2-3% worldwide and imposes a severe clinical and societal burden. Nanodermatology-based solutions appear promising for the proper treatment and management of psoriasis, assisting and enhancing different steps of the process of health-care delivery: from the diagnosis to the therapeutics, paving the way for a personalized approach, based on the specific dysregulated biomarkers.

Combination of UVB Absorbing Titanium Dioxide and Quercetin Nanogel for Skin Cancer Chemoprevention

Sunscreens are widely prescribed and used to prevent skin cancer; however, they have been reported to contain various chemicals which mimic hormones and disrupt hormonal functioning in humans. The aim of this study was to develop topical nanogel for skin cancer prevention using an antioxidant compound quercetin (Qu) and inorganic titanium dioxide (TiO₂). Two formulations of Qu nanocrystals were optimized with low and high concentration of drug using the Box-Behnken design with the quadratic response surface model and further homogenized with TiO₂. Qu nanocrystal (0.08% and 0.12%) formulations showed a particle size of 249.65 ± 2.84 nm and 352.48 ± 3.56 nm with zeta potential of - 14.7 ± 0.41 mV and - 19.6 ± 0.37 mV and drug content of 89.27 ± 1.39% and 90.38 ± 1.81% respectively. Scanning electron microscopy (SEM) images showed rod-shaped nanocrystals with a particle size below 400 nm. Qu (0.08%), Qu (0.12%), Qu (0.12%) + TiO₂ (5%), and Qu (0.12%) + TiO₂ (15%) nanogels showed over 70% drug release with significantly (p < 0.001) enhanced skin deposition of Qu as compare with Qu suspension within 24 h. The average numbers of tumor, tumor volume, and percentage of animals with tumors at onset in the Qu (0.12%) + TiO₂ (15%) nanogel-pretreated group was found to be significantly (p < 0.05) less as compared with the UV only exposed group. Further, Qu (0.12%) + TiO₂ (15%) nanogel significantly (p < 0.001) downregulated COX-2, EP3, EP4, PCNA, and cyclin D1 expressions in contrast to Qu and TiO₂ only pretreated groups. Therefore, novel combination of Qu (0.12%) + TiO₂ (15%) with enhanced skin deposition can be used as a chemopreventive strategy in UVB-induced skin photocarcinogenesis.

In Vitro Drug Dissolution/Permeation Testing of Nanocarriers for Skin Application: a Comprehensive Review

This review highlights in vitro drug dissolution/permeation methods available for topical and transdermal nanocarriers that have been designed to modulate the propensity of drug release, drug penetration into skin, and permeation into systemic circulation. Presently, a few of USFDA-approved in vitro dissolution/permeation methods are available for skin product testing with no specific application to nanocarriers. Researchers are largely utilizing the in-house dissolution/permeation testing methods of nanocarriers. These drug release and permeation methods are pending to be standardized. Their biorelevance with reference to in vivo plasma concentration-time profiles requires further exploration to enable translation of in vitro data for in vivo or clinical performance prediction.

Topical film prepared with Rhus verniciflua extract-loaded pullulan hydrogel for atopic dermatitis treatment

Atopic dermatitis (AD) is characterized by relapsing pruritus and skin dryness. Due to the pathogenic multiplicity and the adverse effects associated with the current therapeutics, development of transdermal drug delivery system is becoming an area of interest. Here, a novel topical film prepared with Rhus verniciflua extract (RVE)-loaded pullulan hydrogel (RVE@PH) was synthesized and tested its therapeutic efficacy on the AD rats modeled by neonatal capsaicin injection method. The RVE@PH was characterized by a Fourier-transform infrared spectroscopy and an in vitro release assay. Rat pups were randomly divided into two groups: vehicle-treated (VEH; n = 5) and capsaicin-treated (n = 15). The latter were given capsaicin subcutaneously at 24 h after birth for AD induction and further divided into three groups (n = 5 per each): not treated (CAP), pullulan hydrogel-applied (PH), and RVE@PH-applied (RVE-PH). The pullulan hydrogel and RVE@PH were topically applied on shoulder lesions for 14 days (from 42 to 56 days after birth). Their phenotypes were compared based on the dermatitis score, epidermal thickness, mast cell infiltration, and serum myeloperoxidase (MPO) activities. The PH group showed significant attenuation in all the aforementioned values compared to the CAP group, suggesting that pullulan hydrogel itself has therapeutic activity against AD. Notably, the attenuations were more potent in the RVE-PH group than the PH group, indicating that the therapeutic efficacy against AD is augmented by the presence of RVE, a loaded pharmaceutic. Collectively, these results indicate that RVE@PH inhibits AD through exerting the dual roles, that is, the pullulan hydrogel-mediated physical and RVE-mediated pharmaceutical actions. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 2325-2334, 2019.

In situ misemgel as a multifunctional dual-absorption platform for nasal delivery of raloxifene hydrochloride: formulation, characterization, and in vivo performance

BACKGROUND

Raloxifene hydrochloride (RLX) is approved by the US Food and Drug Administration for the treatment and prevention of osteoporosis, in addition to reducing the risk of breast cancer in postmenopausal women. RLX has the disadvantages of low aqueous solubility, extensive presystemic intestinal glucuronidation, and first-pass metabolism, resulting in a limited bio-availability of only 2%. The aim of this work was to enhance the bioavailability of RLX via the formulation of an in situ nasal matrix (misemgel) comprising micelles made of vitamin E and D-α-tocopheryl polyethylene glycol 1000 succinate and nanosized self-emulsifying systems (NSEMS).

MATERIALS AND METHODS

Optimization of the RLX-loaded NSEMS was performed using a mixture design. The formulations were characterized by particle size and then incorporated into an in situ nasal gel. Transmission electron microscopy, bovine nasal mucosa ex vivo permeation, and visualization using a fluorescence laser microscope were carried out on the RLX in situ misemgel comparing with raw RLX in situ gel. In addition, the in vivo performance was studied in rats.

RESULTS

The results revealed improved permeation parameters for RLX misemgel compared with control gel, with an enhancement factor of 2.4. In vivo studies revealed a 4.79- and 13.42-fold increased bioavailability for RLX in situ misemgel compared with control RLX in situ gel and commercially available tablets, respectively. The obtained results highlighted the efficacy of combining two different formulations to enhance drug delivery and the benefits of utilizing different possible paths for drug absorption.

CONCLUSION

The developed in situ misemgel matrix could be considered as a promising multifunctional platform for nasal delivery which works based on a dual-absorption mechanism.

Therapeutic Efficacies of Artemisia capillaris Extract Cream Formulation in Imiquimod-Induced Psoriasis Models

A cream formulation containing Artemisia capillaris (AC) extract (ACE) was developed for psoriasis therapy. Although ACE can be dissolved in organic solvents, its topical application is restricted because of toxicities. Therefore, a cream formulation was developed for the convenient and safe local application of ACE on skin lesions. The antipsoriatic properties of the ACE cream were evaluated using an imiquimod- (IMQ-) induced psoriasis-like mouse model. In psoriasis-like mouse models, the cumulative score (redness, thickness, and scaling) of the IMQ + ACE cream group was significantly lower than those of the other groups on day 4 (p < 0.05). The results of the hematoxylin and eosin staining of skin tissues revealed that the epidermal thickness value of the IMQ + ACE cream group was significantly lower than those of the other experimental groups (p < 0.05). The expression level of intracellular adhesion molecule-1 (ICAM-1), which indicates the leukocyte infiltration into the skin and subsequent interactions with keratinocytes, was also lower in the IMQ + ACE cream group than in the IMQ group. These results indicate that ACE cream formulation could be used safely and conveniently for psoriasis treatment.

Antiproliferation of keratinocytes and alleviation of psoriasis by the ethanol extract of Artemisia capillaris

The therapeutic potentials of the ethanol extract of Artemisia capillaris (ACE) for psoriasis were verified in HaCaT cells (as an immortalized human keratinocyte cell line) and imiquimod (IMQ)-induced psoriasis-like mouse models. In HaCaT cells, IC₅₀ value of ACE was 37.5 μg/ml after incubating for 72 hr. The antiproliferation activity of ACE in HaCaT cells was further verified by apoptosis assays. The percentage of apoptotic population in ACE-treated group was significantly higher than that of control group (p < .05). The result of cell cycle arrest assay also supported the observed antiproliferation efficacy of ACE in HaCaT cells. In IMQ-induced psoriasis-like mouse models, the Psoriasis Area and Severity Index score of ACE (50 mg/ml; ACE50)-treated group was significantly lower than that of IMQ group on Day 4 (p < .05). After topical application of ACE on psoriasis-like lesion for 4 days, the epidermal thickness of (IMQ + ACE50) group was significantly lower than that of IMQ group (p < .05). The expression levels of Ki-67 and intracellular adhesion molecule-1 in excised skin tissues of (IMQ + ACE50) group were also lower than those of IMQ group. All these findings suggest that ACE can be used as a promising antipsoriatic agent.

Nanoemulsion as pharmaceutical carrier for dermal and transdermal drug delivery: Formulation development, stability issues, basic considerations and applications

The use of nanoemulsion in augmenting dermal and transdermal effectiveness of drugs has now well established. The development of nanoemulsion based semisolid dosage forms is an active area of present research. However, thickening or liquid-to-semisolid conversion of the nanoemulsions provides opportunities to the formulation scientist to explore novel means of solving instability issues during transformation. Extending knowledge about the explicit role of nature/magnitude of zeta potential, types of emulsifiers and selection of appropriate semisolid bases could place these versatile carriers from laboratory to industrial scale. This article reviews the progressive advancement in the delivery of medicament via nanoemulsion with special reference to the dermal and transdermal administration. It is attempted to explore the most suitable semi solid dosage form for the particular type of nanoemulsion (o/w, w/o and others) and effect of particle size and zeta potential on the delivery of drugs through dermal or transdermal route. Finally, this review also highlights the basic principles and fundamental considerations of nanoemulsion manufacture, application of nanoemulsion based semisolid dosage forms in the dermal/transdermal administration and basic considerations during the nanoemulsion absorption into and through skin.

Size-dependent penetration of nanoemulsions into epidermis and hair follicles: implications for transdermal delivery and immunization

Nanoemulsions have been widely applied to dermal and transdermal drug delivery. However, whether and to what depth the integral nanoemulsions can permeate into the skin is not fully understood. In this study, an environment-responsive dye, P4, was loaded into nanoemulsions to track the transdermal translocation of the nanocarriers, while coumarin-6 was embedded to represent the cargoes. Particle size has great effects on the transdermal transportation of nanoemulsions. Integral nanoemulsions with particle size of 80 nm can diffuse into but not penetrate the viable epidermis. Instead, these nanoemulsions can efficiently fill the whole hair follicle canals and reach as deep as 588 μm underneath the dermal surfaces. The cargos are released from the nanoemulsions and diffuse into the surrounding dermal tissues. On the contrary, big nanoemulsions, with mean particle size of 500 nm, cannot penetrate the stratum corneum and can only migrate along the hair follicle canals. Nanoemulsions with median size, e.g. 200 nm, show moderate transdermal permeation effects among the three-size nanoemulsions. In addition, colocalization between nanoemulsions and immunofluorescence labeled antigen-presenting cells was observed in the epidermis and the hair follicles, implying possible capture of nanoemulsions by these cells. In conclusion, nanoemulsions are advantageous for transdermal delivery and potential in transcutaneous immunization.

Potential and future scope of nanoemulgel formulation for topical delivery of lipophilic drugs

The Nanoemulgel drug delivery system is a formulation related intervention to improve the systemic delivery and therapeutic profile of lipophilic drugs. Nanoemulgel is an amalgamated formulation of two different systems in which nanoemulsion containing drug is incorporated into a gel base. The fusion of the two systems makes this formulation advantageous in several ways. Lipophilic drugs can be easily incorporated and the skin permeability of the incorporated drugs can be enhanced in several folds due to the finely distributed droplets of nanoemulsion phase. As a result, the pharmacokinetic and pharmacodynamic profiles of the lipophilic drugs are improved significantly. An increasing trend in topical nanoemulgel use in recent years has been noticed because of the better acceptability of the preparation to the patients due to their noninvasive delivery, avoidance of gastrointestinal side effects, easier applicability and good therapeutic and safety profile. Despite of having few limitations, nanoemulgel formulation can be considered as a potential and promising candidates for topical delivery of lipophilic drugs in the future. The aim of this review is to evaluate and report the current potential and future scope of nanoemulgel formulation for becoming an effective delivery system for poorly water soluble drugs. In this review, we have summarized and discussed the outcome of different studies on permeability, pharmacokinetic, pharmacodynamic and safety profile of the drugs delivered topically through nanoemulgel. Rationality of use along with the major challenges to overcome for nanoemulgel formulation has been discussed.

Lipid-based oral delivery systems for skin deposition of a potential chemopreventive DIM derivative: characterization and evaluation

The objective of this study was to explore the oral route as a viable potential for the skin deposition of a novel diindolylmethane derivative (DIM-D) for chemoprevention activity. Various lipid-based oral delivery systems were optimized and compared for enhancing DIM-D's oral bioavailability and skin deposition. Preformulation studies were performed to evaluate the log P and solubility of DIM-D. Microsomal metabolism, P-glycoprotein efflux, and caco-2 monolayer permeability of DIM-D were determined. Comparative evaluation of the oral absorption and skin deposition of DIM-D-loaded various lipid-based formulations was performed in rats. DIM-D showed pH-dependent solubility and a high log P value. It was not a strong substrate of microsomal degradation and P-glycoprotein. SMEDDs comprised of medium chain triglycerides, monoglycerides, and kolliphor-HS15 (36.70 ± 0.42 nm). SNEDDs comprised of long chain triglycerides, cremophor RH40, labrasol, and TPGS (84.00 ± 14.14 nm). Nanostructured lipid carriers (NLC) consisted of compritol, miglyol, and surfactants (116.50 ± 2.12 nm). The blank formulations all showed >70 % cell viability in caco-2 cells. Differential Scanning Calorimetry confirmed the amorphization of DIM-D within the lipid matrices while Atomic Force Microscopy showed particle size distribution similar to the dynamic light scattering data. DIM-D also showed reduced permeation across caco-2 monolayer that was enhanced (p < 0.05) by SNEDDs in comparison to SMEDDs and NLC. Fabsolute for DIM-D SNEDDs, SMEDDs, and NLC was 0.14, 0.04, and 0.007, respectively. SNEDDs caused 53.90, 11.32, and 15.08-fold more skin deposition of DIM-D than the free drug, SMEDDs, and NLC, respectively, at 2 h following oral administration and shows a viable potential for use in skin cancer chemoprevention. Graphical Abstract ᅟ.

Capsaicin and Its Role in Chronic Diseases

A significant number of experimental and clinical studies published in peer-reviewed journals have demonstrated promising pharmacological properties of capsaicin in relieving signs and symptoms of non-communicable diseases (chronic diseases). This chapter provides an overview made from basic and clinical research studies of the potential therapeutic effects of capsaicin, loaded in different application forms, such as solution and cream, on chronic diseases (e.g. arthritis, chronic pain, functional gastrointestinal disorders and cancer). In addition to the anti-inflammatory and analgesic properties of capsaicin largely recognized via, mainly, interaction with the TRPV1, the effects of capsaicin on different cell signalling pathways will be further discussed here. The analgesic, anti-inflammatory or apoptotic effects of capsaicin show promising results in arthritis, neuropathic pain, gastrointestinal disorders or cancer, since evidence demonstrates that the oral or local application of capsaicin reduce inflammation and pain in rheumatoid arthritis, promotes gastric protection against ulcer and induces apoptosis of the tumour cells. Sadly, these results have been paralleled by conflicting studies, which indicate that high concentrations of capsaicin are likely to evoke deleterious effects, thus suggesting that capsaicin activates different pathways at different concentrations in both human and rodent tissues. Thus, to establish effective capsaicin doses for chronic conditions, which can be benefited from capsaicin therapeutic effects, is a real challenge that must be pursued.

Characterization of cubosomes as a targeted and sustained transdermal delivery system for capsaicin

Phytantriol- and glycerol monooleate-based cubosomes were produced and characterized as a targeted and sustained transdermal delivery system for capsaicin. The cubosomes were prepared by emulsification and homogenization of phytantriol (F1), glycerol monooleate (F2), and poloxamer dispersions, characterized for morphology and particle size distribution by transmission electron microscope and photon correlation spectroscopy. Their Im3m crystallographic space group was confirmed by small-angle X-ray scattering. An in vitro release study showed that the cubosomes provided a sustained release system for capsaicin. An in vitro diffusion study conducted using Franz diffusion cells indicated that the skin retention of capsaicin from cubosomes in the stratum corneum was much higher (2.75±0.22 μg versus 4.32±0.13 μg, respectively) than that of capsaicin cream (0.72±0.13 μg). The stress testing showed that the cubosome formulations were stable under strong light and high temperature for up to 10 days. After multiapplications on mouse skin, the irritation of capsaicin cubosomes and cream was light with the least amount of side effects. Overall, the present study demonstrated that cubosomes may be a suitable skin-targeted and sustained delivery system for the transdermal administration of capsaicin.