Perillyl alcohol inhibits keratinocyte proliferation and attenuates imiquimod-induced psoriasis like skin-inflammation by modulating NF-κB and STAT3 signaling pathways

Innate lymphoid cell-based immunomodulatory hydrogel microspheres containing Cutibacterium acnes extracellular vesicles for the treatment of psoriasis

Psoriasis is a chronic skin inflammation influenced by dysregulated skin microbiota, with the role of microbiota in psoriasis gaining increasing prominence. Bacterial extracellular vesicles (bEVs) serve as crucial regulators in the interaction between hosts and microbiota. However, the mechanism underlying the therapeutic potential of bEVs from commensal bacteria in psoriasis remains unclear. Here, we investigated the therapeutic role of Cutibacterium acnes (C. acnes)-derived extracellular vesicles (CA-EVs) in psoriasis treatment. To prolong the active duration of CA-EVs, we encapsulated them in gelatin methacrylate (GelMA) to fabricate hydrogel microspheres (CA-EVs@GHM) with sustained release properties. As GelMA degraded, CA-EVs were gradually released, maintaining a high concentration in mouse skin even 96 h post-treatment. In human keratinocyte cells (HaCaT), CA-EVs@GHM enhanced resistance to Staphylococcus aureus (S. aureus), promoted proliferation and migration of HaCaT cells exposed to S. aureus, and significantly reduced the expression of inflammatory genes such as interleukin (IL)-6 and C-X-C motif chemokine ligand 8 (CXCL8). In vivo, CA-EVs@GHM, more potent than CA-EVs alone, markedly attenuated proinflammatory gene expression, including tumor necrosis factor (TNF), Il6, Il17a, Il22 and Il23a in imiquimod (IMQ)-induced psoriasis-like mice, and restored skin barrier function. 16S rRNA sequencing revealed that CA-EVs@GHM might provide therapeutic effects against psoriasis by restoring microbiota diversity on the back skin of mice, reducing Staphylococcus colonization, and augmenting lipid metabolism. Furthermore, flow cytometry analysis showed that CA-EVs@GHM prevented the conversion of type 2 innate lymphoid cells (ILC2) to type 3 innate lymphoid cells (ILC3) in psoriasis-like mouse skin, reducing the pathogenic ILC3 population and suppressing the secretion of IL-17 and IL-22. In summary, our findings demonstrate that the long-term sustained release of CA-EVs alleviated psoriasis symptoms by controlling the transformation of innate lymphoid cells (ILCs) subgroups and restoring skin microbiota homeostasis, thus offering a promising therapy for psoriasis treatment. STATEMENT OF SIGNIFICANCE: Cutibacterium acnes, which is reduced in psoriasis skin, has been reported to promote skin homeostasis by regulating immune balance. Compared to live bacteria, bacterial extracellular vesicles (bEVs) are less prone to toxicity and safety concerns. bEVs play a pivotal role in maintaining bacterial homeostasis and modulating the immune system. However,bEVs without sustained release materials are unable to function continuously in chronic diseases. Therefore, we utilized hydrogel microspheres to encapsulate Cutibacterium acnes (C. acnes)-derived extracellular vesicles (CA-EVs), enabling long term sustained release. Our findings indicate that, CA-EVs loaded gelatin methacrylate hydrogel microspheres (CA-EVs@GHM) showed superior therapeutic effects in treating psoriasis compared to CA-EVs. CA-EVs@GHM exhibited a more significant regulation of pathological type 3 innate lymphoid cells (ILC3) and skin microbiota, providing a promising approach for microbiota-derived extracellular vesicle therapy in the treatment of skin inflammation.

Formulation characterization of lecithin organogel as topical drug delivery system for psoriasis: In-vitro permeation and preclinical evaluation

Psoriasis is a chronic inflammatory and proliferative skin disease that causes pathological skin changes and has a substantial impact on the quality of patient life. Apremilast was approved by the US Food and Drug Administration as an oral medication for psoriasis and is beneficial in mild to moderate conditions for chronic usage. However, 5%-7% of withdrawals were reported due to severe side effects. To address the issue, a localized drug delivery strategy via the topical route may be a viable approach. However, poor physicochemical properties make it vulnerable to passing through the skin, requiring a specialized drug delivery system to demonstrate its full potential via a topical route like lecithin organogel. The formulation was optimized by screening the suitable lecithin type and non-polar solvents based on the gel formation ability of lecithin and the solubility of apremilast in the solvent. The pseudo-ternary diagram was used to optimize the water content required to form the gel. The optimized gel was found to be shear thinning characterized for rheological parameters, in-vitro diffusion studies, and in-vitro skin distribution studies. Preclinical studies in Imiquimod-induced mice showed a better reduction in severity index, cytokine levels, and epidermal hyperplasia from the lecithin organogel group compared to the apremilast oral administration and marketed standard topical gel group. Based on these results, lecithin organogel can be considered a promising approach to deliver molecules like apremilast by topical route in psoriatic-like conditions.

The causal relationship between serum metabolites and the risk of psoriasis: a Mendelian randomization and meta-analysis study

Objective

To explore the influence of serum metabolites on the risk of psoriasis.

Methods

In the initial stage, we applied Mendelian randomization to evaluate the association between 1,400 serum metabolites and the risk of psoriasis. Causal effects were primarily assessed through the Inverse-Variance Weighted method and Wald Ratio's odds ratios, and 95% confidence intervals. False Discovery Rate was used for multiple comparison corrections. Sensitivity analyses were conducted using Cochran's Q Test, MR-PRESSO. MR-Steiger Test was employed to check for reverse causality. In the validation stage, we sought other sources of psoriasis GWAS data to verify the initial results and used meta-analysis to combine the effect sizes to obtain robust causal relationships. In addition, we also conducted metabolic pathway enrichment analysis on known metabolites that have a causal relationship with the risk of psoriasis in both stages.

Results

In the initial stage, we identified 112 metabolites causally associated with psoriasis, including 32 metabolite ratios and 80 metabolites (69 known and 11 unknown). In the validation stage, 24 metabolites (16 known, 1 unknown, and 7 metabolite ratios) were confirmed to have a causal relationship with psoriasis onset. Meta-analysis results showed that the overall effect of combined metabolites was consistent with the main analysis in direction and robust in the causal relationship with psoriasis onset. Of the 16 known metabolites, most were attributed to lipid metabolism, with 5 as risk factors and 8 as protective factors for psoriasis. Peptidic metabolite Gamma-glutamylvaline levels had a negative causal relationship with psoriasis, while exogenous metabolite Catechol sulfate levels and amino acid 3-methylglutaconate levels had a positive causal relationship with the disease onset. The metabolites associated with psoriasis risk in the two stages are mainly enriched in the following metabolic pathways: Glutathione metabolism, Alpha Linolenic Acid and Linoleic Acid Metabolism, Biosynthesis of unsaturated fatty acids, Arachidonic acid metabolism, Glycerophospholipid metabolism.

Conclusion

Circulating metabolites may have a potential causal relationship with psoriasis risk, and targeting specific metabolites may benefit psoriasis diagnosis, disease assessment, and treatment.

Plant Monoterpenes and Essential Oils as Potential Anti-Ageing Agents: Insights from Preclinical Data

Ageing is a natural process characterized by a time-dependent decline of physiological integrity that compromises functionality and inevitably leads to death. This decline is also quite relevant in major human pathologies, being a primary risk factor in neurodegenerative diseases, metabolic disorders, cardiovascular diseases and musculoskeletal disorders. Bearing this in mind, it is not surprising that research aiming at improving human health during this process has burst in the last decades. Importantly, major hallmarks of the ageing process and phenotype have been identified, this knowledge being quite relevant for future studies towards the identification of putative pharmaceutical targets, enabling the development of preventive/therapeutic strategies to improve health and longevity. In this context, aromatic plants have emerged as a source of potential bioactive volatile molecules, mainly monoterpenes, with many studies referring to their anti-ageing potential. Nevertheless, an integrated review on the current knowledge is lacking, with several research approaches studying isolated ageing hallmarks or referring to an overall anti-ageing effect, without depicting possible mechanisms of action. Herein, we aim to provide an updated systematization of the bioactive potential of volatile monoterpenes on recently proposed ageing hallmarks, and highlight the main mechanisms of action already identified, as well as possible chemical entity-activity relations. By gathering and categorizing the available scattered information, we also aim to identify important research gaps that could help pave the way for future research in the field.

Mechanistic Investigation of WWOX Function in NF-kB-Induced Skin Inflammation in Psoriasis

Psoriasis is a chronic inflammatory skin disease characterized by epidermal hyperproliferation, aberrant differentiation of keratinocytes, and dysregulated immune responses. WW domain-containing oxidoreductase (WWOX) is a non-classical tumor suppressor gene that regulates multiple cellular processes, including proliferation, apoptosis, and migration. This study aimed to explore the possible role of WWOX in the pathogenesis of psoriasis. Immunohistochemical analysis showed that the expression of WWOX was increased in epidermal keratinocytes of both human psoriatic lesions and imiquimod-induced mice psoriatic model. Immortalized human epidermal keratinocytes were transduced with a recombinant adenovirus expressing microRNA specific for WWOX to downregulate its expression. Inflammatory responses were detected using Western blotting, real-time quantitative reverse transcription polymerase chain reaction (PCR), and enzyme-linked immunosorbent assay. In human epidermal keratinocytes, WWOX knockdown reduced nuclear factor-kappa B signaling and levels of proinflammatory cytokines induced by polyinosinic: polycytidylic acid [(poly(I:C)] in vitro. Furthermore, calcium chelator and protein kinase C (PKC) inhibitors significantly reduced poly(I:C)-induced inflammatory reactions. WWOX plays a role in the inflammatory reaction of epidermal keratinocytes by regulating calcium and PKC signaling. Targeting WWOX could be a novel therapeutic approach for psoriasis in the future.

Loganic acid protects against ulcerative colitis by inhibiting TLR4/NF-κB mediated inflammation and activating the SIRT1/Nrf2 anti-oxidant responses in-vitro and in-vivo

Ulcerative colitis (UC) is an idiopathic, chronic disorder of the intestines characterized by excessive inflammation and oxidative stress. Loganic acid (LA) is an iridoid glycoside reported to have antioxidant and anti-inflammatory properties. However, the beneficial effects of LA on UC are unexplored yet. Thus, this study aims to explore the potential protective effects of LA and its possible mechanisms. In-vitro models were employed using LPS-stimulated RAW 264.7 macrophage cells, and Caco-2 cells, whereas an in-vivo model of ulcerative colitis was employed using 2.5% DSS in BALB/c mice. Results indicated that LA significantly suppressed the intracellular ROS levels and inhibited the phosphorylation of NF-κB in both RAW 264.7 and Caco-2 cells, contrarily LA activated the Nrf2 pathway in RAW 264.7 cells. In DSS-induced colitis mice, LA significantly alleviated the inflammation and colonic damage by decreasing the pro-inflammatory cytokines (IL-1β, IL-6, TNF-α, and IFN-γ), oxidative stress markers (MDA, and NO), and also expression levels of various inflammatory proteins (TLR4 and NF-кB) which was evidenced by immunoblotting. On the contrary, the release of GSH, SOD, HO-1, and Nrf2 were profoundly increased upon LA treatment.Subsequently, molecular docking studies showed that LA interacts with active site regions of target proteins (TLR4, NF-κB, SIRT1, and Nrf2) through hydrogen bonding and salt bridge interaction. The current findings demonstrated that LA could exhibit a protective effect in DSS-induced ulcerative colitis through its anti-inflammatory and anti-oxidant effects via inactivating the TLR4/NF-κB signaling pathway and activating the SIRT1/Nrf2 pathways.

Reactive Oxygen Species-Responsive Gel-Based Microneedle Patches for Prolonged and Intelligent Psoriasis Management

Psoriasis is an inflammatory skin disease. Microneedle (MN) patches can improve psoriasis treatment outcomes by increasing local drug content in the skin. As psoriasis frequently relapses, developing intelligent MN-based drug delivery systems with prolonged therapeutic drug levels and improved treatment efficiency is of great significance. Here, we designed detachable H₂O₂-responsive gel-based MN patches containing methotrexate (MTX) and epigallocatechin gallate (EGCG) by using EGCG as both cross-linkers for needle-composited materials and anti-inflammatory drugs. The gel-based MNs had dual-mode drug release kinetics, which quickly released MTX diffusively and sustainably released EGCG in an H₂O₂-responsive way. Compared with dissolving MNs, the gel-based MNs extended skin retention of EGCG, leading to prolonged reactive oxygen species (ROS) scavenging effects. The ROS-responsive MN patches that transdermally delivered antiproliferative and anti-inflammatory drugs improved treatment outcomes in both psoriasis-like and prophylactic psoriasis-like animal models.

Targeting Nrf2 with 3 H-1,2-dithiole-3-thione to moderate OXPHOS-driven oxidative stress attenuates IL-17A-induced psoriasis

Psoriasis, a chronic autoimmune disease characterized by the hyperproliferation of keratinocytes in the epidermis and parakeratosis, significantly impacts quality of life. Interleukin (IL)- 17A dominates the pathogenesis of psoriasis and facilitates reactive oxygen species (ROS) accumulation, which exacerbates local psoriatic lesions. Biologic treatment provides remarkable clinical efficacy, but its high cost and unignorable side effects limit its applications. 3 H-1,2-Dithiole-3-thione (D3T) possesses compelling antioxidative capacities against several diseases through the nuclear factor erythroid 2-related factor 2 (Nrf2) cascade. Hence, we aimed to evaluate the effect and mechanism of D3T in psoriasis. We found that D3T attenuates skin thickening and scaling by inhibiting IL-17A-secreting γδT cells in imiquimod (IMQ)-induced psoriatic mice. Interleukin-17A markedly enhanced IL-6 and IL-8 expression, lipid peroxidation, the contents of nitric oxide and hydrogen peroxide, oxidative phosphorylation and the MAPK/NF-κB pathways in keratinocytes. IL-17A also inhibited the Nrf2-NQO1-HO-1 axis and the activities of superoxide dismutase and glutathione peroxidase. D3T significantly reversed these parameters in IL-17A-treated keratinocytes. ML-385, a Nrf2 neutralizer, failed to improve D3T-induced anti-inflammatory and antioxidative effects in IL-17A-treated keratinocytes. We conclude that targeting Nrf2 with D3T to diminish oxidative and inflammatory damage in keratinocytes may attenuate psoriasis.

Mesua assamica (King&Prain) kosterm. Bark ethanolic extract attenuates chronic restraint stress aggravated DSS-induced ulcerative colitis in mice via inhibition of NF-κB/STAT3 and activation of HO-1/Nrf2/SIRT1 signaling pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Mesua Assamica (King & prain) Kosterm. (MA) is an evergreen endemic medicinal tree available in Assam in India and other parts of south Asia. The bark of the plant is traditionally used for ant-malarial activity and treating fevers. It was reported to have anti-oxidant, anti-inflammatory, anti-diabetic, anti-cancer and anti-malarial properties, but no research findings have been reported about its protective activity on intestinal inflammatory disorders like ulcerative colitis (UC) yet.

AIM OF THE STUDY

The aim of the current study is to evaluate the anti-ulcerative property of ethanolic extract of MA (MAE) in-vitro on GloResponse™ NF-кB-RE-luc2P HEK 293 cells for its anti-oxidant and anti-inflammatory activities and in-vivo chronic restraint stress aggravated dextran sodium sulfate (DSS)-induced UC model.

MATERIALS AND METHODS

The chemical constituents of MAE were identified by LC-MS/MS. The in-vitro effects of MAE on GloResponse™ NF-кB-RE-luc2P HEK 293 cells stimulated with TNF-α 30 ng/ml were investigated for its potential therapeutic effects. Parameters such as body weights, behavioural, colonoscopy, colon lengths and spleen weights were measured and recorded in chronic restraint stress aggravated DSS-induced UC model in C57BL/6 mice. Histological, cytokines and immunoblotting analysis in the colon tissues were determined to prove its anti-inflammatory and anti-oxidant activities.

RESULTS

MAE poses significant anti-oxidant and anti-inflammatory activity in-vitro in GloResponse™ NF-кB-RE-luc2P HEK 293 cells evidenced by DCFDA and immunoflourescence assay. MAE treatment at 100 mg/kg and 200 mg/kg for 14 consecutive days has reduced Disease activity Index (DAI), splenomegaly and improved the shortened colon length and sucrose preference in mice. MAE treatment has increased the levels of anti-oxidants like GSH and reduced the levels of MDA, MPO and nitrite levels in colon tissues. Moreover, MAE has ameliorated neutrophil accumulation, mucosal and submucosal inflammation and crypt density evidenced by histopathology. Furthermore, MAE treatment significantly reduced the increased pro-inflammatory cytokines like IL-6, IL-1β and TNF-α. we found from immunoblotting that there is a concomitant decrease in protein expression of NF-κB, STAT3 signalling cascades and phosphorylation of IKBα with an increase in Nrf2, SOD2, HO-1 and SIRT1 in colon tissues. In addition, we have performed molecular docking studies confirming that phytochemicals present in the MAE have a stronger binding ability and druggability to the NF-κB, Nrf2 and SIRT1 proteins.

CONCLUSIONS

MAE exhibited significant anti-colitis activity on chronic restraint stress aggravated DSS-induced ulcerative colitis via regulating NF-κB/STAT3 and HO-1/Nrf2/SIRT1 signaling pathways.

A double-edged sword: ROS related therapies in the treatment of psoriasis

In the onset and progression of psoriasis, redox imbalance is a vital factor. It's widely accepted that too much reactive oxygen species (ROS) always make psoriasis worse. Recent research, however, has shown that the accumulation of ROS is not entirely detrimental, as it helps reduce psoriasis lesions by inhibiting epidermal proliferation and keratinocyte death. As a result, ROS appears to have two opposing effects on the treatment of psoriasis. In this review, the current ROS-related therapies for psoriasis, including basic and clinical research, are presented. Additionally, the design and therapeutic benefits of various drug delivery systems and therapeutic approaches are examined, and a potential balance between anti-oxidative stress and ROS accumulation is also trying to be investigated.

Perillyl alcohol attenuates chronic restraint stress aggravated dextran sulfate sodium-induced ulcerative colitis by modulating TLR4/NF-κB and JAK2/STAT3 signaling pathways

BACKGROUND

Ulcerative colitis (UC) is the most prevalent chronic inflammatory immune bowel disease. The modernization of lifestyle accompanied by the stress to cope with the competition has resulted in a new range of complications where stress became a critical contributing factor for many diseases, including UC. Hence there is an urgent need to develop a dual role in curtailing both systemic and neuroinflammation. Perillyl alcohol (POH) is a natural essential oil found in lavender, peppermint, cherries etc and has been widely studied for its strong anti-inflammatory, antioxidant and anti-stress properties.

HYPOTHESIS/PURPOSE

POH regulates the various inflammatory signaling cascades involved in chronic inflammation by inhibiting farnesyltransferase  enzyme. Several studies reported that POH could inhibit the phosphorylation of  NF-κB, STAT3 and promote the endogenous antioxidant enzymes like Nrf2 via farnesyltransferase enzyme inhibition.  Also, the effects of POH against UC is not known yet. Thus, this study aims to explore the anti-ulcerative properties of POH on stress aggravated ulcerative colitis in C57BL/6 mice.

METHODS

Ulcerative colitis was induced by duel exposure of chronic restraint stress (day 1 to day 28) and 2.5% dextran sulphate sodium (day8 to day14) in mice. POH treatment 100 and 200 mg/kg was administred from day14 ti day28 following oral route of administration. Disease activity index, colonoscopy, western blot analysis and histological analysis, neurotransmitter analysis and Gene expression studies were perofomerd to asses the anti-colitis effects of POH.

RESULTS

The treatment reversed the oxidative stress and inflammatory response by inhibiting TLR4/NF-kB pathway, and IL-6/JAK2/STAT3 pathway in both isolated mice colons and brains. The inhibition of these pathways resulted in a decrease in pro-inflammatory cytokines like IL-6, IL-1β and TNF-α. The treatment improved the physiological and histological changes with decreased ulcerations as examined by colonic endoscopy and Haematoxylin and Eosin staining. The treatment also improved the behavior response as it increased mobility time which was reduced by chronic restrained stress. This was due to increased satiety neurotransmitters like dopamine and serotonin and decreased cortisol in mice brains.

CONCLUSION

These results infer that POH has significant anti-colitis activity on chronic restraint stress aggravated DSS-induced UC in mice.

The Role of KEAP1-NRF2 System in Atopic Dermatitis and Psoriasis

The Kelch-like erythroid cell-derived protein with cap‘n’collar homology-associated protein 1 (KEAP1)-nuclear factor erythroid-2-related factor 2 (NRF2) system, a thiol-based sensor-effector apparatus, exerts antioxidative and anti-inflammatory effects and maintains skin homeostasis. Thus, NRF2 activation appears to be a promising treatment option for various skin diseases. However, NRF2-mediated defense responses may deteriorate skin inflammation in a context-dependent manner. Atopic dermatitis (AD) and psoriasis are two common chronic inflammatory skin diseases caused by a defective skin barrier, dysregulated immune responses, genetic predispositions, and environmental factors. This review focuses on the role of the KEAP1-NRF2 system in the pathophysiology of AD and psoriasis and the therapeutic approaches that utilize this system.