Antipsoriatic Effects of Wannachawee Recipe on Imiquimod-Induced Psoriasis-Like Dermatitis in BALB/c Mice

Development of Betulin-Loaded Nanostructured Lipid Carriers for the Management of Imiquimod-Induced Psoriasis

Psoriasis is a complex and persistent autoimmune skin disease. The present research focused on the therapeutic evaluation of betulin-loaded nanostructured lipid carriers (BE-NLCs) towards managing psoriasis. The BE-NLCs were synthesized using the emulsification cum solidification method, exhibiting a spherical shape with a particle size of 183.5±1.82nm and a narrow size distribution window (PDI: 0.142±0.05). A high zeta potential -38.64±0.05mV signifies the relative stability of the nano-dispersion system. BE-NLCs show a drug loading and entrapment efficiency of 47.35±3.25% and 87.8±7.86%, respectively. In vitro release study, BE NLCs show a cumulative percentage release of 90.667±5.507% over BE-sol (57.334±5.03%) and BD-oint (42±4.58%) for 720min. In an ex vivo 24-h permeation study, % cumulative amount permeated per cm2 was found to be 55.667±3.33% from BE-NLCs and 32.012±3.26% from BE-sol, demonstrating a better permeability of 21.66% when compared to the standard formulation BD-oint. The in vivo anti-psoriatic activity in the IMQ-induced model shows topical application of BE-sol, BE-NLCs, and BD-oint resulted in recovery rates of 56%, 82%, and 65%, respectively, based on PASI (Psoriasis Area and Severity Index) score. Notably, BE-NLCs demonstrated a more significant reduction in spleen mass, indicating attenuation of the local innate immune system in psoriatic mice. Reductions in TNF-α, IL-6, and IL-17 levels were observed in both BE-sol and BE-NLCs groups compared to the disease control (DC) group, with BE-NLCs exhibiting superior outcomes (74.05%, 44.76%, and 49.26% reduction, respectively). Soy lecithin and squalene-based NLCs could be better carrier system for the improvement of the therapeutic potential of BE towards management of psoriasis.

Preparation and characterization of solid lipid nanoparticles encapsulated noscapine and evaluation of its protective effects against imiquimod-induced psoriasis-like skin lesions

Psoriasis is a chronic inflammatory skin disease characterized by thickening the epidermis with erythema, scaling, and proliferation. Noscapine (NOS) has several anti-inflammatory, anti-angiogenic, and anti-fibrotic effects, but its low solubility and large size results in its lower efficacy in the clinic. In this regard, solid lipid nanoparticles (SLN) encapsulated NOS (SLN-NOS) were fabricated using the well-known response surface method based on the central composite design and modified high-shear homogenization and ultrasound method. As a result, Precirol® was selected as the best lipid base for the SLN formulation based on Hildebrand-Hansen solubility parameters, in which SLN-NOS 1 % had the best zeta potential (-35.74 ± 2.59 mV), average particle size (245.66 ± 17 nm), polydispersity index (PDI, 0.226 ± 0.09), high entrapment efficiency (89.77 %), and ICH-based stability results. After 72 h, the SLN-NOS 1 % released 83.23 % and 58.49 % of the NOS at pH 5.8 and 7.4, respectively. Moreover, Franz diffusion cell's results indicated that the skin levels of NOS for SLN and cream formulations were 46.88 % and 13.5 % of the total amount, respectively. Our pharmacological assessments revealed that treatment with SLN-NOS 1 % significantly attenuated clinical parameters, namely ear thickness, length, and psoriasis area and severity index, compared to the IMQ group. Interestingly, SLN-NOS 1 % reduced the levels of interleukin (IL)-17, tumor necrosis factor-α, and transforming growth factor-β, while elevating IL-10, compared to the IMQ group. Histology studies also showed that topical application of SLN-NOS 1 % significantly decreased parakeratosis, hyperkeratosis, acanthosis, and inflammation compared to the IMQ group. Taken together, SLN-NOS 1 % showed a high potential to attenuate skin inflammation.

Phytochemical investigation, structural elucidation, in silico study and anti-psoriatic activity of potent bioactive from Betula utilis

Psoriasis is a chronic autoimmune pathological condition characterized by hyperactivation of proinflammatory cytokines (IL-6, TNF-α, IL-17, IL-23, etc.). Severe drug-associated toxicities like hepatotoxicity and nephrotoxicity (Methotrexate), teratogenicity (Tazarotene), hypercholesterolemia (Cyclosporine) and hypercalcemia (tacalcitol), are the forefront challenges that demand an alternative approach for the treatment of psoriasis. In the present study, a natural lead molecule 'Betulin' (BE, lup-20(29)-ene-3b,28-diol) was isolated from Betula utilis and subsequently, structure-based molecular docking was employed to identify the molecular target for psoriasis. The computational analysis reflects better affinity of BE towards pro-inflammatory cytokine as compared to standard drugs. Apart from this BE shows a greater affinity towards the overexpressed Glut-1 receptor in comparison to standard drug Metformin (Met). Based on the in silico screening the isolated lead compound was further processed for the evaluation of anti-psoriatic activity via imiquimod (IMQ 5%) induced psoriasis-like skin inflammation model. In vivo screening models were characterized by different parameters (psoriasis area and severity index (PASI) scores, macroscopically and behavioral evaluation, splenomegaly, cytokine levels and histological changes) and compared among the experimental groups. The experimental finding reflects comparable results of PASI score, i.e., 57.14% and 61.9% recovery of test BE-solution (180 mg/kg) and standard Betamethasone di-propionate ointment (BD-oint.0.5 mg/g), respectively. Focusing on other parameters, BE shows relative results such as an enhanced macroscopically with behavioral conditions, reducing the expression of proinflammatory cytokine as well as restoring histological changes with that of BD. These findings suggest that BE-isolated phytoconstituents from Betula utilis could be a potential agent and a step closer to psoriasis treatment. HIGHLIGHTPsoriasis is a multifaceted, immunologically mediated disease consequences production of high levels of proinflammatory mediators and overexpression of Glut-1 transporters that trigger keratinocyte proliferation and inflammatory cascades.A Himalayan silver birch, Betula utilis (Bhojpatra) contains many steroidal terpenes which are responsible for various pharmacological activities that could be exploited in drug development in psoriasis.The computational analysis of BE reflects a better affinity toward the proinflammatory cytokines with their target receptors and indicates a satisfactory range with a slight deviation from Jorgensen and Lipinski's rule and possesses a significant drug choice for psoriasis.Preclinical findings of BE-solution (BE-sol) give a positive response towards IMQ-induced psoriasis-like skin inflammation model.[Figure: see text]Communicated by Ramaswamy H. Sarma.

Preclinical Demonstration of a Novel Treatment with High Efficacy and No Detectable Toxicity for Inflammatory Skin Conditions including Psoriasis

Although the management options for psoriasis have progressed with the use of systemic agents, there are few efficacious nonsteroidal topical therapies for patients with limited or lower grade disease. The effects of allopurinol (Allo) and glutathione (GSH) were examined in two different in vitro models for psoriasis. In the first model, human immortalized keratinocytes (HaCaT) were treated with M5 cocktail (IL-17A, IL-22, oncostatin M, IL-1α, and TNF-α) in four interventional groups (control, Allo, oxypurinol (Oxy), and methotrexate (MTX)). The number of live and dead cells was determined after treatment for 48 and 72 hrs. Allo decreased cell proliferation (total cells) without increasing cell death compared to both its xanthine oxidase inhibiting metabolite Oxy and a standard agent in clinical use, MTX. In the second model, a human psoriatic skin equivalent (PSE) culture system, cells were treated with vehicle control, Allo and GSH (as monotherapies and in combination), and vitamin D (VitD) for 2 and 6 days followed by histological analysis and altered gene expression. The combined exposure to Allo and GSH was equivalent to a standard antipsoriasis agent VitD in the inhibition of both proliferative and replicative markers. Histologic examination of the tissue at 6 days of exposure to VitD resulted in loss of the integrity of the squamous/epithelial continuity whereas tissue integrity was preserved with Allo and GSH exposure. The additional exposure of GSH to Allo reversed the increased thickness of the dermis layer caused by Allo exposure alone. Taken together, this data shows that topical Allo and GSH may have a synergistic effect with low toxicity and constitute a therapeutic advantage over current nonsteroidal therapies in the treatment of inflammatory skin conditions marked by increased cell proliferation such as psoriasis.

A promising impact of oral administration of noscapine against imiquimod-induced psoriasis-like skin lesions

Objective

Psoriasis is a chronic inflammatory autoimmune disease. The effectiveness of noscapine has been employed as a helpful treatment for various disorders and subjected to recent theoretical breakthroughs.

Materials and Methods

Psoriasis-like lesions were induced by topical application of 5% imiquimod (IMQ) (10 mg/cm2 of skin) in male Balb/c mice and then medicated with a single oral dose of methotrexate (MET) as a positive control or daily oral treatment of noscapine (5, 15 and 45 mg/kg). In this way, skin inflammation intensity, psoriatic itchiness, psoriasis area severity index (PASI) score, ear length, thickness, and organ weight were daily measured. At the end of the study, histological and immunohistochemical and enzyme-linked immunosorbent assays (ELISA, for pro-/anti-inflammatory factors) were performed in each ear.

Results

IMQ caused psoriasis-like lesions. Noscapine markedly alleviated macroscopic parameters, namely ear thickness, ear length, skin inflammation, itching, and organ weight, as well as microscopic parameters including, pathology and Ki67 and p53, and tissue immunological mediators, such as tumour necrosis factor (TNF-α), interleukin (IL)-10, transforming growth factor (TGF-β), interferon-γ (IFN-γ ), IL-6, IL-17, and IL-23p19 in the psoriatic skin in a concentration manner (p<0.05-<0.001).

Conclusion

Therefore, noscapine with good pharmacological properties has considerable effects on psoriasis inflammation.

Augmented Transdermal Delivery of Curcumin for the Effective Management of Plaque Psoriasis - Design, Formulation, Characterisation, and In Vivo Studies

Psoriasis is a recurrent, life-threatening anti-inflammatory condition that affects nearly 1-3% of the global population. It is an autoimmune illness distinguished by hyperplasia of skin cells or fast skin cell development, resulting in abnormally irritating scales and skin patches. Curcumin, as a selective phosphorylase kinase inhibitor, actively suppresses inflammation and keratinocyte proliferation in psoriasis. However, limited solubility in water and poor skin permeability poses a significant hurdle in curcumin's topical effectiveness in psoriasis. The present study focuses on enhancing the solubility and skin permeability of curcumin for better transdermal application. Curcumin-loaded invasomes were formulated, and a factorial design was applied to study the effect of the type of terpenes and their concentrations on the properties of prepared invasomes. A topical gel was formulated using the optimised invasomal formulation which was further evaluated for anti-psoriatic potential in BALB/c mice. The optimised formulation showed 85.84 ± 0.56% entrapment efficiency and a vesicle size of 302.33 ± 1.53 nm. The invasomal gel of the optimised formulation showed a permeation flux of 3 times greater than the plain gel. In vivo studies demonstrated that the invasomal gel of curcumin promoted faster and earlier recovery in psoriatic mice than conventional curcumin gel.

Efficacy of stem cell secretome loaded in hyaluronate sponge for topical treatment of psoriasis

Psoriasis vulgaris is an inflammatory disease characterized by distinctive skin lesions and dysregulated angiogenesis. Recent research uses stem cell secretion products (CM); a set of bioactive factors with therapeutic properties that regulate several cellular processes, including tissue repair and angiogenesis. The aim of this work was to evaluate the effect of CM of Wharton's gelatin MSC (hWJCM) in a treatment based on the bioactivation of a hyaluronic acid matrix (HA hWJCM) in a psoriasiform-like dermatitis (PD) mouse model. A preclinical study was conducted on PD mice. The effect of hWJCM, Clobetasol (Clob) gold standard, HA Ctrl, and HA hWJCM was tested topically evaluating severity of PD, mice weight as well as skin, liver, and spleen appearance. Treatment with either hWJCM, HA Ctrl or HA hWJCM, resulted in significant improvement of the PD phenotype. Moreover, treatment with HA hWJCM reduced the Psoriasis Area Severity Index (PASI), aberrant angiogenesis, and discomfort associated with the disease, leading to total recovery of body weight. We suggest that the topical application of HA hWJCM can be an effective noninvasive therapeutic solution for psoriasis, in addition to other skin diseases, laying the groundwork for future studies in human patients.

The Therapeutic Effect of Tacrolimus in a Mouse Psoriatic Model is Associated with the Induction of Myeloid-derived Suppressor Cells

Objectives

Topical administration of Tacrolimus (TAC) is efective in the treatment of psoriasis in human patients and in mouse models. Previously, we showed that, though promoting the proliferative expansion of CD4⁺Foxp3⁺ regulatory T cells (Tregs), TNFR2 was protective in mouse psoriasis model. We thus examined the role of TNFR2 signal in the efect of TAC in the treatment of mouse psoriasis.

Methods

To this end, psoriasis was induced in WT, or TNFR1 KO, or TNFR2 KO mice, and the psoriatic mice were treated with or without IMQ.

Results

The results showed that TAC treatment potently inhibited the development of psoriasis in WT and TNFR1 KO mice, but not in TNFR2 KO mice. However, the treatment of TAC failed to induce the expansion of Tregs in psoriatic mice. In addition to playing a decisive role in the activation of Tregs, TNFR2 stimulates the generation and activation of myeloid-derived suppressor cells (MDSCs). This led us to found that the topical treatment with TAC markedly increased the number of MDSCs in the spleen of WT and TNFR1 KO mice, but not in TNFR2 KO mice. Consequently, TAC potently decreased serum levels of IL-17A, INF-γ, and TNF and their mRNA levels in the inflamed skin lesion.

Conclusion

Therefore, our study for the first time found that the therapeutic efect of TAC in psoriasis is associated with the expansion of MDSCs in a TNFR2-dependent manner.

Successful treatment of refractory erythrodermic psoriasis with traditional Thai herbal medicine

BACKGROUND

Thai herbal formulations have been used traditionally in Thailand for the treatment of psoriasis. However, there is still a lack of scientific data supporting the effects of Thai herbal formulations in psoriasis treatment.

OBJECTIVES

This study aimed to demonstrate the therapeutic effects of Thai herbal formulations for the treatment of erythrodermic psoriasis.

MATERIALS AND METHODS

All Thai herbal formulations (haematic tonic, lymphatic treatment, skin treatment) were obtained from a traditional Thai medicine doctor, Mr. Somporn Chanwanitsakul. The effects of Thai herbal formulations in a patient with erythrodermic psoriasis were assessed for four weeks. Primary outcome, psoriasis area and severity index (PASI) and secondary outcome, safety data and dermatology life quality index (DLQI) measurements were evaluated at baseline and four weeks. Then, in vitro biological activities (antioxidant, anti-microbial, cytotoxic effects, and anti-inflammatory) of Thai herbal formulations were determined to promote the therapeutic effects.

RESULTS

Thai herbal formulations were safe and effective in the treatment of erythrodermic psoriasis and had a modest positive impact on the DQLI of the patient. In addition, in vitro studies have shown that all Thai herbal formulations revealed remarkable anti-oxidant and anti-inflammatory potential to support their therapeutic activities. However, the Thai herbal formulations possessed weak intrinsic antibacterial activities against all tested bacterial strains (MIC and MBC E. coli, S. aureus, S. pyogenes, P. aeruginosa: > 256 µg/ml).

CONCLUSION

The findings indicated that successful treatment of erythrodermic psoriasis with Thai herbal formulations was involved in their anti-oxidant and anti-inflammatory activities. They could be considered as an alternative treatment for refractory erythrodermic psoriasis.

Topical Formulation of Noscapine, a Benzylisoquinoline Alkaloid, Ameliorates Imiquimod-Induced Psoriasis-Like Skin Lesions

Psoriasis is considered an autoimmune inflammatory disease. The disease is spread and diagnosed by the infiltration of inflammatory mediators and cells into the epidermis. Recent theoretical developments have focused on the effectiveness of noscapine (NOS) as a potential alkaloid for being used as a valuable treatment for different diseases. In the present study, psoriasis-like dermatitis was induced on the right ear pinna surface of male Balb/c mice by topical application of imiquimod (IMQ) for ten consecutive days, which was treated with noscapine (0.3, 1, 3, and 10% w/v) or clobetasol (0.05% w/v) as a positive control. The levels of ear length, thickness, severity of skin inflammation, psoriatic itch, psoriasis area severity index (PASI) score, and body weight were measured daily. On the 10^th day of study, each ear was investigated for inflammation, fibrosis, proliferation, and apoptosis using histopathological (H&E and Masson's trichrome staining) and immunohistochemistry (Ki67 and p53 staining) assays. Furthermore, the levels of inflammatory biomarkers were characterized by an enzyme-linked immunosorbent assay (ELISA). The results confirmed IMQ-induced psoriasis for five consecutive days. In contrast, noscapine significantly reduced the ear length, thickness, severity of skin inflammation, psoriatic itch and body weight, tumor necrosis factor-α (TNF-α), transforming growth factor-β (TGF-β), interferon-gamma (IFN-γ), interleukin 6 (IL-6), IL-17, and IL-23p19 in a concentration-dependent manner (P < 0.001–0.05 for all cases). Overall, topical noscapine significantly ameliorated both the macroscopical and microscopical features of psoriasis. However, further clinical investigations are required to translate the effects to clinics.

Chloroform Extract of Plumbago zeylanica Linn. Roots Ameliorates the Epidermal Thickness of Imiquimod-induced Psoriatic Mice through Cell Cycle and Apoptosis

Introduction: Psoriasis vulgaris is a chronic skin disease which is characterized by recurrent scales on skin. The global prevalence of this disease has increased in ten years. Plumbagin is an active compound in the P. zeylanica Linn. Some recent studies revealed that P. zeylanica Linn extracts have the antiproliferative activity, which is used for treatment of some human diseases. The aim of this study was to investigated the effect of Chloroform extract of P. zeylanica Linn roots (CEP) on epidermal thickness of Imiquimod-induced psoriatic mice. Methods: This was a post-test only control group design. A total of 42 male BALB/c mice was divided into six groups. Mice in treatment groups orally received 25, 50, and 100 mg/kg body weight CEP, respectively while positive control orally received 1 mg/kg body weight Methotrexate for seven days. Evaluation of epidermal thickness based on histological changes, serum IL-23 level by ELISA, and Cyclin-dependent kinase 2, Cyclin A, and Caspase-3 expressions by immunohistochemistry. Results: Administrations of CEP decreased the epidermal thickness of psoriatic plaques in all treatment groups (p = 0.002, 0.003, and 0.016 respectively) compared to negative control but it did not reduce the serum IL-23 level.  The expressions of CDK2 and Cyclin A reduced in T2 and T3 groups and the expression of Caspase-3 increased was only in T3 group. Conclusion: Chloroform extract of P. zeylanica Linn roots administrations reduce the epidermal thickness of Imiquimod-induced psoriatic mice by inhibition of keratinocyte cell cycle and induction of Caspase-3 expression.

Cubosomal Betamethasone-Salicylic Acid Nano Drug Delivery System for Enhanced Management of Scalp Psoriasis

Introduction

Betamethasone dipropionate (BD), a potent corticosteroid, and salicylic acid (SA), a keratolytic agent, have been used in combination to treat scalp psoriasis; however, undesirable side effects associated with their prolonged topical use are inevitable. In this study, BD and SA were loaded into cubosomes, a nanoparticulate system with outstanding biocompatibility, bio-adhesivity and penetration power.

Methods

Design of experiments (DOE) was utilized to prepare thirteen different cubosomal dispersions by emulsification technique using glycerol monoolein (GMO) as a lipid phase and Poloxamer 407 (P407) as a surfactant, sodium carboxymethyl cellulose (SCMC) was added to enhance the dispersions’ rheological properties. The thirteen dispersions were in-vitro characterized for their particle size, polydispersity index (PDI), zeta potential, BD and SA content and rheological behaviour. The desirability of an optimized formula (OF) was set to the smallest particle size, lowest zeta-potential and highest viscosity. The OF was in-vitro characterized for the same parameters in addition to transmission electron microscope imaging and in-vitro drug release. The OF’s anti-psoriatic activity was evaluated in-vivo using an imiquimod-induced psoriasis model.

Results

The OF achieved a particle size of 197.4 ± 9.47 nm, a PDI of 0.443 ± 0.025, a zeta potential of −44.4 ± 0.141mv, BD content of 105.85 ± 2.290%, SA content of 88.855 ± 2.920% with shear-thinning rheological behaviour and completed in-vitro drug release within 2–3 hours. The in-vivo studies confirmed the cubosomes’ higher anti-psoriatic efficacy over the commercial product with lower changes in ear thickness, spleen to body weight ratio, psoriasis area severity index score and improved histopathological findings.

Conclusion

The developed BD SA-loaded cubosomes exhibit promising anti-psoriatic activity attributed to its nano-size and unique lipid content, with enhanced skin penetration and modified rheological properties; increasing the formulation’s in-contact duration with the scalp resulting in lower application frequency and thus reduced BD and SA associated side effects.

Development of Topical Nanoemulgel Using Combined Therapy for Treating Psoriasis

This study focuses on the development of topical formulation of methoxsalen using Babchi oil as formulation component that can be applied at body surfaces providing sustained delivery and enhanced penetration of methoxsalen leading to significant epidermal localization and better anti-psoriatic activity. The combination of psoralens, that is, methoxsalen (synthetic) and Babchi oil (natural) has been developed into nanoemulgel formulations. A total of four nanoemulsion formulations was developed using Babchi oil as oil phase and Tween 80 as surfactant by high-pressure homogenization method. The prepared nanoemulsions were characterized for entrapment efficiency, mean droplet size, and zeta potential. Based on characterization results, the optimized nanoemulsion formulation(s) were incorporated into the carbopol gel base to make a nanoemulgel. The prepared nanoemulgel formulations were analyzed for pH, drug content determination, spreadability, viscosity, ex vivo skin permeation, and in vivo studies. The nanoemulsions showed droplet size between 51.3 and 146.7 nm, entrapment efficiency of 92.76%-98.10%, and zeta potential of -28.1 to -54.89 mev. The nanoemulsions showed varied in vitro drug release. In ex vivo skin permeation, nanoemulgel (NG2) showed increased penetration and localized accumulation of methoxsalen across the skin compared with plain gel. Ex vivo results were substantiated by in vivo results showing significant amelioration of hyperproliferative skin symptoms. The promising results suggested that nanoemulgel system is a suitable carrier for the topical delivery of methoxsalen-Babchi oil.

Self-assembled tacrolimus-loaded lecithin-chitosan hybrid nanoparticles for in vivo management of psoriasis

Lecithin-chitosan hybrid nanoparticles are emerging as a promising nanocarrier for topical drug delivery. They could achieve a maximized encapsulation of hydrophobic drugs due to the lipophilic nature of lecithin that comprises the core while enhancing retention in the upper skin layers using the positively charged polymeric coat of chitosan. The aim of this study is to incorporate tacrolimus; a hydrophobic anti-proliferative agent into lecithin chitosan hybrid nanoparticles by ethanolic injection technique using a suitable co-solvent to enhance encapsulation of the drug and allow a satisfactory release profile in the upper skin layers. Tacrolimus was successfully incorporated into the synthesized particles using olive oil and Tween 80 as co-solvents, with particle size (160.9 nm ± 15.9 and 118.7 nm ± 13.3, respectively) and EE (88.27% ± 4.3 and 66.72% ± 1.8, respectively). The in vitro drug release profile showed a faster release pattern for the Tween 80-containing particles over a 48-hour period (79.98% vs. 35.57%), hence, were selected for further investigation. The hybrid nanoparticles achieved significantly higher skin deposition than the marketed product (63.51% vs. 34.07%) through a 24-hour time interval, particularly, to the stratum corneum and epidermis skin layers. The in vivo results on IMQ-mouse models revealed superior anti-psoriatic efficacy of the synthesized nanoparticles in comparison to the marketed product in terms of visual observation of the skin condition, PASI score and histopathological examination of autopsy skin samples. Additionally, the in vivo drug deposition showed superior skin deposition of the nanoparticles compared to the marketed product (74.9% vs. 13.4%).

Cudraxanthone D Ameliorates Psoriasis-like Skin Inflammation in an Imiquimod-Induced Mouse Model via Inhibiting the Inflammatory Signaling Pathways

Psoriasis is a chronic inflammatory skin disease accompanied by excessive keratinocyte proliferation. Corticosteroids, vitamin D3 analogs, and calcineurin inhibitors, which are used to treat psoriasis, have diverse adverse effects, whereas natural products are popular due to their high efficiency and relatively low toxicity. The roots of the Cudrania tricuspidata (C. tricuspidata) are known to have diverse pharmacological effects, among which the anti-inflammatory effect is reported as a potential therapeutic agent in skin cells. Nevertheless, its effectiveness against skin diseases, especially psoriasis, is not fully elucidated. Here, we investigated the effect of cudraxanthone D (CD), extracted from the roots the C. tricuspidata Bureau, on psoriasis using an imiquimod (IMQ)-induced mouse model and the tumor necrosis factor (TNF)-α/interferon (IFN)-γ-activated keratinocytes. IMQ was topically applied to the back skin of C57BL/6 mice for seven consecutive days, and the mice were orally administered with CD. This resulted in reduced psoriatic characteristics, such as the skin thickness and Psoriasis Area Severity Index score, and the infiltration of neutrophils in IMQ-induced skin. CD inhibited the serum levels of TNF-α, immunoglobulin G2a, and myeloperoxidase, and the expression of Th1/Th17 cells in splenocytes. In TNF-α/IFN-γ-activated keratinocytes, CD reduced the expressions of CCL17, IL-1β, IL-6, and IL-8 by inhibiting the phosphorylation of STAT1 and the nuclear translocation of NF-kB. Taken together, these results suggest that CD could be a potential drug candidate for the treatment of psoriasis.

Anti-Psoriatic Effects of Middle Fragment of Chlamydial Plasmid-Encoded Protein pGP3 in an Imiquimod-Induced Psoriasis Mouse Model

Background

Previously, we demonstrated that the chlamydial protein pGP3 forms a stable complex with LL-37 to neutralize its proinflammatory activity during the pathogenesis of psoriasis. The middle domain of pGP3 (pGP3M) is critical for the binding and neutralization of LL-37. Here, we further examined the mechanism underlying pGP3-mediated inhibition of psoriasis progression and evaluated the inhibitory effect of pGP3M on the development of psoriasis-like skin lesions in mice.

Material/Methods

Stock solutions of pGP3M and pGP3 (100 μg/mL) were prepared using sterile ultrapure water and intramuscularly injected into the left leg of the imiquimod (IMQ)-induced psoriasis mouse model. The severity of skin lesions was evaluated based on the psoriasis area and severity index score and ear skin thickness. The skin biopsy and blood samples were collected on the 8^th day for histological analysis and inflammatory cytokines detection.

Results

Erythema, scaling, and thickening were observed on the dorsal skin and the right ear skin of IMQ-treated mice. Treatment with pGP3 and pGP3M alleviated the IMQ-induced erythema, inflammatory cell infiltration, and scaly plaques. Compared with IMQ-treated and PBS-treated mice, pGP3- and PGP3M-treated mice had less inflammatory cell infiltration in skin tissues and had significantly reduced IL-17A, IFN-γ, and IL-22 levels in serum.

Conclusions

The anti-psoriatic efficacy of exogenous pGP3M was similar to that of pGP3. This indicated that pGP3M attenuated the IMQ-induced inflammatory and psoriatic symptoms in mice by binding and inhibiting LL-37. Further research is needed to examine the toxicity of pGP3 and pGP3M before clinical trial evaluation.

Rapamycin Alleviates 2,3,7,8-Tetrachlorodibenzo-p-dioxin-Induced Aggravated Dermatitis in Mice with Imiquimod-Induced Psoriasis-Like Dermatitis by Inducing Autophagy

Recently, the mTOR signaling has emerged as an important player in the pathogenesis of psoriasis. We previously found that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced psoriatic skin inflammation was related to the inhibition of autophagy in keratinocytes. However, the effects and detailed molecular mechanisms of the mTOR inhibitor rapamycin and TCDD on psoriasis in vivo remain to be elucidated. In this study, we aimed to evaluate the effects of rapamycin and TCDD on skin lesions in imiquimod (IMQ)-induced psoriasis using a mouse model. TCDD aggravated skin inflammation in an IMQ-induced psoriatic mouse model. Furthermore, TCDD increased the expression of aryl hydrocarbon receptor (AHR), CYP1A1, proinflammatory cytokines, oxidative stress markers (NADPH oxidase (Nox) 2, Nox4), and phosphorylated P65NF-ĸB, whereas the expression of autophagy-related factors and the antioxidant marker nuclear factor-erythroid 2-related factor 2 (NRF2) decreased. Rapamycin reduced the aggravated skin inflammation induced by TCDD and restored TCDD-induced autophagy suppression and the increase of AHR expression, oxidative stress, and inflammatory response in the skin lesions of a psoriatic mouse model. In conclusion, we demonstrated that rapamycin alleviates TCDD-induced aggravated dermatitis in mice with imiquimod-induced psoriasis-like dermatitis through AHR and autophagy modulation.

The Protective Effects of 18β-Glycyrrhetinic Acid on Imiquimod-Induced Psoriasis in Mice via Suppression of mTOR/STAT3 Signaling

Psoriasis is recognized as an autoimmune and inflammatory dermatosis, which is estimated to affect 2-3% of the population worldwide. 18β-Glycyrrhetinic acid (GA), one of the main ingredients of Licorice (Glycyrrhiza glabra L.), has been shown to have numerous pharmacological effects such as antioxidative, antitumor, and anti-inflammatory activities. However, it remains to be explored whether GA has antipsoriatic effect on psoriasis. In this study, we evaluated the protective effect of GA on psoriasis and its mechanisms of action in imiquimod-induced psoriasis-like mouse model. Results indicated that GA dramatically improved psoriatic lesions and reduced psoriasis area and severity index scores. GA also suppressed the mRNA levels of IL-6, TNF-α, IL-17, IL-23, and IL-1β in the skin and increased the proportion of CD4+ Foxp3+ regulatory T cells (Tregs) in both lymph nodes and spleens. Its anti-inflammatory and immunomodulatory activities may be related to its suppression of the STAT3 and mTOR signaling. In conclusion, GA ameliorated the symptoms of psoriasis, at least in part, through inhibition of inflammatory cytokines and STAT3/mTOR signaling and activation of Tregs in both lymph nodes and spleens. These effects are expected to be beneficial in the treatment and prevention of psoriasis.

Hispidulin alleviates imiquimod-induced psoriasis-like skin inflammation by inhibiting splenic Th1/Th17 cell population and keratinocyte activation

Psoriasis is a chronic inflammatory skin disease characterized by hyperproliferation and abnormal differentiation of epidermal keratinocytes accompanied by increased infiltration of immune cells. Previous studies have demonstrated that hispidulin (4',5,7-trihydroxy-6-methoxyflavone, HPD) has various pharmacological benefits such as anti-fungal, anti-inflammation, and anti-allergic effects. This study investigated the effectiveness of HPD to treat psoriasis using an imiquimod (IMQ)-induced mouse model and activated keratinocytes. IMQ was topically applied to the back skin of mice for six consecutive days, and the mice were orally administered HPD. Based on the histological observation and immunological analysis, oral administration of HPD suppressed psoriatic characteristics including skin thickness, psoriasis area severity index, transepidermal water loss, and neutrophil infiltration. HPD alleviated pathologically increased levels of immunoglobulin G2a, myeloperoxidase, and tumor necrosis factor-α. Splenic Th1 and Th17 cell populations were also reduced by HPD in the murine model. In addition, in activated keratinocytes, HPD inhibited gene expression of Th1- and Th17-associated cytokines and chemokines, and phosphorylation of mitogen-activated protein kinases and nuclear factor-κB. In summary, HPD alleviates psoriasis skin inflammation in vivo and in vitro. Therefore, we suggest that HPD would be a potent therapeutic candidate for the treatment of psoriasis.

Methotrexate-Loaded Nanostructured Lipid Carrier Gel Alleviates Imiquimod-Induced Psoriasis by Moderating Inflammation: Formulation, Optimization, Characterization, In-Vitro and In-Vivo Studies

INTRODUCTION

Methotrexate exhibits poor cutaneous bioavailability and systemic side effects on topical administration, so there is an unmet need for a novel carrier and its optimized therapy. Methotrexate-loaded nanostructured lipid carriers (MTXNLCs) were formulated and characterized to determine in vitro drug release and evaluate the role of MTXNLC gel in the topical treatment of psoriasis.

METHODS

A solvent diffusion technique was employed to prepare MTXNLCs, which was optimized using 32 full factorial designs. The mean diameter and surface morphology of MTXNLCs was evaluated. The crystallinity of lyophilized MTXNLCs was characterized by differential scanning calorimetry (DSC) and powder X-ray diffraction (XRD). MTXNLCs were integrated in 1% w/w Carbopol 934 P gel base, and in vitro skin deposition studies in human cadaver skin (HCS) were carried out.

RESULTS

The optimized MTXNLCs were rod-shaped, with an average particle size of 253 ± 8.65 nm, a zeta potential of -26.4±0.86 mV, and EE of 54.00±1.49%. DSC and XRD data confirmed the formation of NLCs. Significantly higher deposition of MTX was found in HCS from MTXNLC gel (71.52 ±1.13%) as compared to MTX plain gel (38.48±0.96%). In vivo studies demonstrated significant improvement in therapeutic response and reduction in local side effects with MTXNLCs-loaded gel in the topical treatment of psoriasis. Anti-psoriatic efficacy of MTXNLCs 100 ug/cm2 compared with plain MTX gel was evaluated using imiquimod (IMQ)-induced psoriasis in BALB/c mice. The topical application of MTXNLCs to the mouse ear resulted in a significant reduction of psoriatic area and severity index, oxidative stress, inflammatory cytokines like TNF-α, IL-1β, and IL-6 and IMQ-induced histopathological alterations in mouse ear samples.

CONCLUSION

Developed formulation of MTXNLC gel demonstrated better anti-psoriatic activity and also displayed prolonged and sustained release effect, which shows that it can be a promising alternative to existing MTX formulation for the treatment of psoriasis.

Dysfunction of regulatory T cells mediated by AKT-FOXO1 signaling pathway occurs during the development of psoriasis

Psoriasis is an immune-mediated skin disease with abnormal T cells. Regulatory T cells (Treg) are a kind of cell group with immunosuppressive effects. This study aimed to explore the role of Treg cells in the pathogenesis of psoriasis and its possible mechanism. Imiquimod induced psoriasis mice model was conducted. The skin lesions were evaluated according to the psoriasis area and severity index (PASI). Skin biopsies were taken for HE staining and immunohistochemical staining of IL-23, IL-17, IL-33 and TNF-α. CD4⁺CD25⁺ Treg cells were isolated. The proportions of Treg cells, cell proliferation, and immunosuppressive activity were analyzed by flow cytometry. The expression of AKT, Foxo1, pAKT, pFoxo1 protein, and the localization of Foxo1 protein in Treg cells were detected by western blot and immunofluorescence. The results showed that the psoriasis mice model was established successfully. There was no significant difference in the proportion of Treg cells between the two groups (P > 0.05). The cell proliferation abilities were decreased, and the immunosuppressive functions of Treg cells were weakened in the psoriatic group (P < 0.05). Western blot showed that pAKT and pFoxo1 levels of Treg cells were significantly increased in the psoriatic group (P < 0.05). Immunofluorescence showed that Foxo1 was mainly expressed in the nucleus of Treg cells in the control group, whereas expressed in the cytoplasm in the psoriasis group. Therefore, we concluded that the cell proliferation and immunosuppressive dysfunction of Treg cells mediated by AKT-FOXO1 signaling pathway may occurs during the development of psoriasis.

Piperlongumine regulates epigenetic modulation and alleviates psoriasis-like skin inflammation via inhibition of hyperproliferation and inflammation

Psoriasis is an autoimmune skin disease, where chronic immune responses due to exaggerated cytokine signaling, abnormal differentiation, and evasion of keratinocytes apoptosis plays a crucial role in mediating abnormal keratinocytes hyperproliferation. From the therapeutic perspective, the molecules with strong anti-proliferative and anti-inflammatory properties could have tremendous relevance. In this study, we demonstrated that piperlongumine (PPL) treatment effectively abrogated the hyperproliferation and differentiation of keratinocytes by inducing ROS-mediated late apoptosis with loss of mitochondrial membrane potential. Besides, the arrest of cell cycle was found at Sub-G1 phase as a result of DNA fragmentation. Molecularly, inhibition of STAT3 and Akt signaling was observed with a decrease in proliferative markers such as PCNA, ki67, and Cyclin D1 along with anti-apoptotic Bcl-2 protein expression. Keratin 17 is a critical regulator of keratinocyte differentiation, and it was found to be downregulated with PPL significantly. Furthermore, prominent anti-inflammatory effects were observed by inhibition of lipopolysaccharide (LPS)/Imiquimod (IMQ)-induced p65 NF-κB signaling cascade and strongly inhibited the production of cytokine storm involved in psoriasis-like skin inflammation, thus led to the restoration of normal epidermal architecture with reduction of epidermal hyperplasia and splenomegaly. In addition, PPL epigenetically inhibited histone-modifying enzymes, which include histone deacetylases (HDACs) of class I (HDAC1-4) and class II (HDAC6) evaluated by immunoblotting and HDAC enzyme assay kit. In addition, our results show that PPL effectively inhibits the nuclear translocation of p65 and a histone modulator HDAC3, thus sequestered in the cytoplasm of macrophages. Furthermore, PPL effectively enhanced the protein-protein interactions of HDAC3 and p65 with IκBα, which was disrupted by LPS stimulation and were evaluated by Co-IP and molecular modeling. Collectively, our findings indicate that piperlongumine may serve as an anti-proliferative and anti-inflammatory agent and could serve as a potential therapeutic option in treating psoriasis.

Development, characterization and evaluation of topical methotrexate-entrapped deformable liposome on imiquimod-induced psoriasis in a mouse model

The aim of this study was to prepare and characterize topical methotrexate (MTX) with different percentages (0.05%, 0.1%, 0.25% and 0.5%) entrapped in deformable liposomes using phosphatidylcholine and oleic acid. The effectiveness and sub-acute toxicity of these topical formulations were investigated in imiquimod (IMQ)-induced psoriasis in a mouse model (IMQP). The particle sizes of formulations were around 100 nm with a mean zeta potential of -72.87 mV. The entrapment efficiency (EE%) of MTX in liposomal formulations were more than 85%. Franz cell permeability studies indicated that permeation of MTX through the healthy BALB/c mice skin is very low; however, in the inflammatory skin, which was induced by IMQ it was significant (50%). Liposomal MTX (LM 0.05 and 0.1%) caused significant reduction of thickness score dose-dependently in IMQP compared to the injected MTX. Moreover, investigation of the inflammatory factor and pathological examinations of skin proved the superiority of the LM treating group. Pathological examinations also showed there are no toxicity in organs of the mice that received the LM. Blood cell count test didn't show any abnormality. MTX-entrapped deformable liposomes could be a topical option in future for the treatment of human psoriasis with a less toxicity and merit further investigations.

Qingpeng Ointment Ameliorates Inflammatory Responses and Dysregulation of Itch-Related Molecules for Its Antipruritic Effects in Experimental Allergic Contact Dermatitis

The pathogenesis of itchy skin diseases including allergic contact dermatitis (ACD) is complicated and the treatment of chronic itch is a worldwide problem. One traditional Tibetan medicine, Qingpeng ointment (QP), has been used in treatment of ACD in China for years. In this study we used HPLC and LC/MS analysis, combined with a BATMAN-TCM platform, for detailed HPLC fingerprint analysis and network pharmacology of QP, and investigated the anti-inflammatory and antipruritic activities of QP on ACD induced by squaric acid dibutylester (SADBE) in mice. The BATMAN-TCM analysis provided information of effector molecules of the main ingredients of QP, and possible chronic dermatitis-associated molecules and cell signaling pathways by QP. In ACD mice, QP treatment suppressed the scratching behavior induced by SADBE in a dose-dependent manner and inhibited the production of Th1/2 cytokines in serum and spleen. Also, QP treatment reversed the upregulation of mRNAs levels of itch-related genes in the skin (TRPV4, TSLP, GRP, and MrgprA3) and DRGs (TRPV1, TRPA1, GRP, and MrgprA3). Furthermore, QP suppressed the phosphorylation of Erk and p38 in the skin. In all, our work indicated that QP can significantly attenuate the pathological alterations of Th1/2 cytokines and itch-related mediators, and inhibit the phosphorylation of MAPKs to treat the chronic itch.

Esculetin Ameliorates Psoriasis-Like Skin Disease in Mice by Inducing CD4+Foxp3+ Regulatory T Cells

Psoriasis is an autoimmune and inflammatory skin disease affecting around 2-3% of the world's population. Patients with psoriasis need extensive treatments with global immunosuppressive agents that may cause severe side effects. Esculetin, a type of coumarins, is an active ingredient extracted mainly from the bark of Fraxinus rhynchophylla, which has been used to treat inflammatory and autoimmune diseases in China. However, the antipsoriatic effects of esculetin have not been reported. In this study, we aimed to investigate the effects of esculetin on psoriatic skin inflammation in a mouse model and explored the potential molecular mechanisms underlying its action. We found that esculetin ameliorated the skin lesion and reduced PASI scores as well as weight loss in imiquimod-induced psoriasis-like mice, accompanied with weakened proliferation and differentiation of keratinocytes and T cell infiltration in esculetin-treated psoriatic mice. In addition, esculetin reduced the frequency of CD8⁺CD44^highCD62L^low effector T cells in psoriatic mice. In contrast, it increased the frequency of CD4⁺Foxp3⁺ Tregs in both lymph nodes and spleens of the psoriatic mice while promoting the differentiation of CD4⁺CD25^- T cells into CD4⁺Foxp3⁺ Tregs in vitro. Interestingly, depleting CD4⁺Foxp3⁺ Tregs largely reversed esculetin-mediated reduction in PASI scores, indicating that esculetin attenuates murine psoriasis mainly by inducing CD4⁺Foxp3⁺ Tregs. Furthermore, the mRNA levels of proinflammatory cytokines in the psoriatic mouse skin, including IL-6, IL-17A, IL-22, IL-23, TNF-α, and IFN-γ, were dramatically decreased by the treatment with esculetin. Finally, we found that esculetin inhibited the phosphorylation of IKKα and P65 in the psoriatic skin, suggesting that it inhibits the activation of NF-κB signaling. Thus, we have demonstrated that esculetin attenuates psoriasis-like skin lesion in mice and may be a potential therapeutic candidate for the treatment of psoriasis in clinic.

Chlamydial Plasmid-Encoded Protein pGP3 Inhibits Development of Psoriasis-Like Lesions in Mice

Background

The anti-microbial protein cathelicidin LL-37 plays an important role in the pathogenesis of psoriasis by inducing inflammation. Our previous study showed that the chlamydial plasmid-encoded protein pGP3 forms a stable complex with LL-37 to neutralize its pro-inflammatory activity. Here, we explored whether pGP3 can inhibit the development of lesions in mice with imiquimod-induced psoriasis.

Material/Methods

The protein pGP3 was expressed in bacteria and purified using glutathione-conjugated agarose beads and a precision protease. The ability of the purified pGP3 to block chemotaxis mediated by LL-37 was tested in vitro using bone marrow-derived neutrophils. The ability of the protein to inhibit the development of psoriasis-like lesions was tested by topically or subcutaneously administering pGP3 in doses of 10 or 50 μg to mice previously treated with imiquimod. Mouse skin was evaluated using the psoriasis area and severity index (PASI) score and photography. Skin biopsies were taken on day 8 and analyzed histologically.

Results

Purified pGP3 inhibited LL-37-mediated chemotaxis. Mice treated with 50 μg pGP3 showed clinical improvement with less severe erythema, infiltration, and scales; these mice also showed thinner dermis and less hyperkeratosis, parakeratosis, and inflammatory cell infiltration than mice treated with without 10 μg pGP3.

Conclusions

PGP3 can inhibit the development of psoriasis-like lesions in mice, possibly through its ability to bind LL-37. Future work should examine the mechanisms underlying this therapeutic effect.