Dihydroartemisinin ameliorates psoriatic skin inflammation and its relapse by diminishing CD8+ T-cell memory in wild-type and humanized mice

Adjunctive Chinese medicine therapy reduces relapse of psoriasis vulgaris after discontinuation of biologics: a prospective registry-based cohort study

BACKGROUND

Biologics have revolutionized psoriasis treatment; however, relapse of psoriasis after discontinuation of biologics remains unresolved.

OBJECTIVE

To assess the impact of adjunctive Chinese medicine (CM) therapy on relapse of psoriasis vulgaris (PV) after discontinuation of biologics.

METHODS

We constructed a prospective cohort study through a psoriasis case registry platform that enrolled patients treated with biologics (in combination with or without CM). The endpoint event was relapse, defined as loss of psoriasis area and severity index (PASI) 75.

RESULTS

A total of 391 patients completed the study and were included in the analysis, of whom 169 (43.2%) experienced relapse during follow-up. To minimize the bias, a 1:1 propensity score matching (PSM) was performed, generating matched cohorts of 156 individuals per group. Adjuvant CM therapy significantly associated with reduced incidence of relapse (HR =0.418, 95% CI = 0.289 ∼ 0.604, p < 0.001), and the protective effect of CM in the subgroup analysis was significant. In addition, PASI 90 response and disease duration were associated with relapse (p < 0.05).

CONCLUSION

Adjunctive CM therapy is associated with reduced relapse incidence in PV after discontinuation of biologics.

Cornuside alleviates psoriasis-like skin lesions in mice by relieving inflammatory effects

Psoriasis is a chronic inflammatory skin disease substantially affecting the quality of life, with no complete cure owing to its complex pathogenesis. Cornuside, a major bioactive compound present in Cornus officinalis Sieb. et Zucc., which is a well-known traditional Chinese medicine with a variety of biological and pharmacological activities, such as anti-apoptotic, antioxidant, and anti-inflammatory properties. However, its effects on psoriasis remain unclear. Our preliminary analysis of network pharmacology showed that cornuside may be involved in psoriasis by regulating the inflammatory response and IL-17 signaling pathway. Thus, we investigated the protective role and mechanism of cornuside in the pathogenesis of psoriasis in an imiquimod (IMQ)-induced psoriasis mouse model. In-vivo experiments demonstrated that cornuside-treated mice had reduced skin erythema, scales, thickness, and inflammatory infiltration. The Psoriasis Area Severity Index score was significantly lower than that of the IMQ group. Flow cytometry analysis indicated that cornuside effectively inhibited Th1- and Th17-cell infiltration and promoted aggregation of Th2 cells in skin tissues. Cornuside also inhibited the infiltration of macrophages to the skin. Furthermore, in-vitro experiments indicated that cornuside also decreased the polarization of M1 macrophages and reduced the levels of associated cytokines. Western blotting demonstrated that cornuside suppressed the phosphorylation of c-Jun N-terminal kinase (JNK) and extracellular receptor kinase (ERK) in bone marrow-derived macrophages. Our findings indicate that cornuside has a protective effect against IMQ-induced psoriasis by inhibiting M1 macrophage polarization through the ERK and JNK signaling pathways and modulating the infiltration of immune cells as well as the expression of inflammatory factors.

Prednisone combined with Dihydroartemisinin attenuates systemic lupus erythematosus by regulating M1/M2 balance through the MAPK signaling pathway

OBJECTIVE

Dihydroartemisinin (DHA) plays a very important role in various diseases. However, the precise involvement of DHA in systemic lupus erythematosus (SLE), relation to the equilibrium between M1 and M2 cells, remains uncertain. Therefore, we aimed to investigate the role of DHA in SLE and its effect on the M1/M2 cells balance.

METHODS

SLE mice model was established by pristane induction. Flow cytometry was employed to measure the abundance of M1 and M2 cells within the peripheral blood of individuals diagnosed with SLE. The concentrations of various cytokines, namely TNF-α, IL-1β, IL-4, IL-6, and IL-10, within the serum of SLE patients or SLE mice were assessed via ELISA. Immunofluorescence staining was utilized to detect the deposition of IgG and complement C3 in renal tissues of the mice. We conducted immunohistochemistry analysis to assess the expression levels of Collagen-I, a collagen protein, and α-SMA, a fibrosis marker protein, in the renal tissues of mice. Hematoxylin-eosin staining, Masson's trichrome staining, and Periodic acid Schiff staining were used to examine histological alterations. In this study, we employed qPCR and western blot techniques to assess the expression levels of key molecular markers, namely CD80 and CD86 for M1 cells, as well as CD206 and Arg-1 for M2 cells, within kidney tissue. Additionally, we investigated the involvement of the MAPK signaling pathway. The Venny 2.1 online software tool was employed to identify shared drug-disease targets, and subsequently, the Cytoscape 3.9.2 software was utilized to construct the "disease-target-ingredient" network diagram. Protein-protein interactions of the target proteins were analyzed using the String database, and the network proteins underwent enrichment analysis for Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathways.

RESULTS

The results showed that an increase in M1 cells and a decrease in M2 cells within the peripheral blood of individuals diagnosed with SLE. Further analysis revealed that prednisone (PDN) combined with DHA can alleviate kidney damage and regulate the balance of M1 and M2 cells in both glomerular mesangial cells (GMC) and kidney. The MAPK signaling pathway was found to be involved in SLE kidney damage and M1/M2 balance in the kidney. Furthermore, PDN and/or DHA were found to inhibit the MAPK signaling pathway in GMC and kidney.

CONCLUSION

We demonstrated that PDN combined with DHA attenuates SLE by regulating M1/M2 balance through MAPK signaling pathway. These findings propose that the combination of PDN and DHA could serve as a promising therapeutic strategy for SLE, as it has the potential to mitigate kidney damage and reinstate the equilibrium of M1 and M2 cells.

Dihydroartemisinin-driven selective anti-lung cancer proliferation by binding to EGFR and inhibition of NRAS signaling pathway-induced DNA damage

Chemotherapeutic agents can inhibit the proliferation of malignant cells due to their cytotoxicity, which is limited by collateral damage. Dihydroartemisinin (DHA), has a selective anti-cancer effect, whose target and mechanism remain uncovered. The present work aims to examine the selective inhibitory effect of DHA as well as the mechanisms involved. The findings revealed that the Lewis cell line (LLC) and A549 cell line (A549) had an extremely rapid proliferation rate compared with the 16HBE cell line (16HBE). LLC and A549 showed an increased expression of NRAS compared with 16HBE. Interestingly, DHA was found to inhibit the proliferation and facilitate the apoptosis of LLC and A549 with significant anti-cancer efficacy and down-regulation of NRAS. Results from molecular docking and cellular thermal shift assay revealed that DHA could bind to epidermal growth factor receptor (EGFR) molecules, attenuating the EGF binding and thus driving the suppressive effect. LLC and A549 also exhibited obvious DNA damage in response to DHA. Further results demonstrated that over-expression of NRAS abated DHA-induced blockage of NRAS. Moreover, not only the DNA damage was impaired, but the proliferation of lung cancer cells was also revitalized while NRAS was over-expression. Taken together, DHA could induce selective anti-lung cancer efficacy through binding to EGFR and thereby abolishing the NRAS signaling pathway, thus leading to DNA damage, which provides a novel theoretical basis for phytomedicine molecular therapy of malignant tumors.

Heterogeneity and plasticity of tissue-resident memory T cells in skin diseases and homeostasis: a review

Skin tissue-resident memory T (Trm) cells are produced by antigenic stimulation and remain in the skin for a long time without entering the peripheral circulation. In the healthy state Trm cells can play a patrolling and surveillance role, but in the disease state Trm cells differentiate into various phenotypes associated with different diseases, exhibit different localizations, and consequently have local protective or pathogenic roles, such as disease recurrence in vitiligo and maintenance of immune homeostasis in melanoma. The most common surface marker of Trm cells is CD69/CD103. However, the plasticity of tissue-resident memory T cells after colonization remains somewhat uncertain. This ambiguity is largely due to the variation in the functionality and ultimate destination of Trm cells produced from memory cells differentiated from diverse precursors. Notably, the presence of Trm cells is not stationary across numerous non-lymphoid tissues, most notably in the skin. These cells may reenter the blood and distant tissue sites during the recall response, revealing the recycling and migration potential of the Trm cell progeny. This review focuses on the origin and function of skin Trm cells, and provides new insights into the role of skin Trm cells in the treatment of autoimmune skin diseases, infectious skin diseases, and tumors.

Zhen-Wu-Tang ameliorates lupus nephritis by diminishing renal tissue-resident memory CD8+ T cells via suppressing IL-15/STAT3 pathway

Zhen-Wu-Tang (ZWT), a conventional herbal mixture, has been recommended for treating lupus nephritis (LN) in clinic. However, its mechanisms of action remain unknown. Here we aimed to define the immunological mechanisms underlying the effects of ZWT on LN and to determine whether it affects renal tissue-resident memory T (TRM) cells. Murine LN was induced by a single injection of pristane, while in vitro TRM cells differentiated with IL-15/TGF-β. We found that ZWT or mycophenolate mofetil treatment significantly ameliorated kidney injury in LN mice by decreasing 24-h urine protein, Scr and anti-dsDNA Ab. ZWT also improved renal pathology and decreased IgG and C3 depositions. In addition, ZWT down-regulated renal Desmin expression. Moreover, it lowered the numbers of CD8+ TRM cells in kidney of mice with LN while decreasing their expression of TNF-α and IFN-γ. Consistent with in vivo results, ZWT-containing serum inhibited TRM cell differentiation induced by IL-15/TGF-β in vitro. Mechanistically, it suppressed phosphorylation of STAT3 and CD122 （IL2/IL-15Rβ）expression in CD8+ TRM cells. Importantly, ZWT reduced the number of total F4/80+CD11b+ and CD86+, but not CD206+, macrophages in the kidney of LN mice. Interestingly, ZWT suppressed IL-15 protein expression in macrophages in vivo and in vitro. Thus, we have provided the first evidence that ZWT decoction can be used to improve the outcome of LN by reducing CD8+ TRM cells via inhibition of IL-15/IL-15R /STAT3 signaling.

Artemisinin and its derivatives as promising therapies for autoimmune diseases

Artemisinin, a traditional Chinese medicine with remarkable antimalarial activity. In recent years, studies demonstrated that artemisinin and its derivatives (ARTs) showed anti-inflammatory and immunoregulatory effects. ARTs have been developed and gradually applied to treat autoimmune and inflammatory diseases. However, their role in the treament of patients with autoimmune and inflammatory diseases in particular is less well recognized. This review will briefly describe the history of ARTs use in patients with autoimmune and inflammatory diseases, the theorized mechanisms of action of the agents ARTs, their efficacy in patients with autoinmmune and inflammatory diseases. Overall, ARTs have numerous beneficial effects in patients with autoimmune and inflammatory diseases, and have a good safety profile.

Dihydroartemisinin inhibits restenosis after balloon angioplasty via circHSPA4/miR-19a-5p axis

Dihydroartemisinin (DHA) inhibits restenosis following balloon angioplasty. However, data on the mechanisms of DHA activity in restenosis remains scant. Here, we investigated the role of circRNAs in mediating the inhibitory activity of DHA in neointimal formation. We used total RNA sequencing data to profile the expression of mRNA, circRNA and small RNA in sham, vascular balloon injury (VBI) and DHA-treated groups. CCK8 and EdU assays were employed to analyze cell proliferation, while qRT-PCR and Western blot were used to analyze the RNA or protein expression. In addition, we used RNA immunoprecipitation and luciferase reporter assay to assess the binding of circHSPA4 with miR-19a-5p. RNA sequencing demonstrated that circHSPA4 was upregulated in VBI. Treatment with DHA effectively suppressed the upregulation of the circHSPA4. In addition, analysis of platelet-derived growth family factor bb (PDGFbb)-induced HA-VSMCs showed upregulation of circHSPA4, which was associated with cell proliferation and differentiation. CircHSPA4 was shown to induce dedifferentiation and proliferation of smooth muscle cells. PDGFBB-induced overexpression of CircHSPA4 in HA-VSMCs led to suppression of miR-19a-5p, a phenomenon that was reversed by DHA, in concentration-dependent fashion. In addition, miR-19a-5p reduced the dedifferentiation and proliferation of the smooth muscle cells. Our data demonstrated that CircHSPA4 regulates proliferation and differentiation of smooth muscle cells. DHA and miR-19a-5p modulates CircHSPA4 and can be used as coated drugs on balloon catheter to improve the success rate of vascular remodeling.

Dihydroartemisinin alleviates erosive bone destruction by modifying local Treg cells in inflamed joints: A novel role in the treatment of rheumatoid arthritis

Treg cell-based therapy has exhibited promising efficacy in combatting rheumatoid arthritis (RA). Dihydroartemisinin (DHA) exerts broad immunomodulatory effects across various diseases, with its recent spotlight on T-cell regulation in autoimmune conditions. The modulation of DHA on Treg cells and its therapeutic role in RA has yet to be fully elucidated. This study seeks to unveil the influence of DHA on Treg cells in RA and furnish innovative substantiation for the potential of DHA to ameliorate RA. To this end, we initially scrutinized the impact of DHA-modulated Treg cells on osteoclast (OC) formation in vitro using Treg cell-bone marrow-derived monocyte (BMM) coculture systems. Subsequently, employing the collagen-induced arthritis (CIA) rat model, we validated the efficacy of DHA and probed its influence on Treg cells in the spleen and popliteal lymph nodes (PLN). Finally, leveraging deep proteomic analysis with data-independent acquisition (DIA) and parallel accumulation-serial fragmentation (PASEF) technology, we found the alterations in the Treg cell proteome in PLN by proteomic analysis. Our findings indicate that DHA augmented suppressive Treg cells, thereby impeding OC formation in vitro. Consistently, DHA mitigated erosive joint destruction and osteoclastogenesis by replenishing splenic and joint-draining lymph node Treg cells in CIA rats. Notably, DHA induced alterations in the Treg cell proteome in PLN, manifesting distinct upregulation of alloantigen Col2a1 (Type II collagen alfa 1 chain) and CD8a (T-cell surface glycoprotein CD8 alpha chain) in Treg cells, signifying DHA's targeted modulation of Treg cells, rendering them more adept at sustaining immune tolerance and impeding bone erosion. These results unveil a novel facet of DHA in the treatment of RA.

Artemisinins: Promising drug candidates for the treatment of autoimmune diseases

Autoimmune diseases are characterized by the immune system's attack on one's own tissues which are highly diverse and diseases differ in severity, causing damage in virtually all human systems including connective tissue (e.g., rheumatoid arthritis), neurological system (e.g., multiple sclerosis) and digestive system (e.g., inflammatory bowel disease). Historically, treatments normally include pain-killing medication, anti-inflammatory drugs, corticosteroids, and immunosuppressant drugs. However, given the above characteristics, treatment of autoimmune diseases has always been a challenge. Artemisinin is a natural sesquiterpene lactone initially extracted and separated from Chinese medicine Artemisia annua L., which has a long history of curing malaria. Artemisinin's derivatives such as artesunate, dihydroartemisinin, artemether, artemisitene, and so forth, are a family of artemisinins with antimalarial activity. Over the past decades, accumulating evidence have indicated the promising therapeutic potential of artemisinins in autoimmune diseases. Herein, we systematically summarized the research regarding the immunoregulatory properties of artemisinins including artemisinin and its derivatives, discussing their potential therapeutic viability toward major autoimmune diseases and the underlying mechanisms. This review will provide new directions for basic research and clinical translational medicine of artemisinins.

Immune cells in the epithelial immune microenvironment of psoriasis: emerging therapeutic targets

Psoriasis is a chronic autoimmune inflammatory disease characterized by erroneous metabolism of keratinocytes. The development of psoriasis is closely related to abnormal activation and disorders of the immune system. Dysregulated skin protective mechanisms can activate inflammatory pathways within the epithelial immune microenvironment (EIME), leading to the development of autoimmune-related and inflammatory skin diseases. In this review, we initially emphasized the pathogenesis of psoriasis, paying particular attention to the interactions between the abnormal activation of immune cells and the production of cytokines in psoriasis. Subsequently, we delved into the significance of the interactions between EIME and immune cells in the emergence of psoriasis. A thorough understanding of these immune processes is crucial to the development of targeted therapies for psoriasis. Finally, we discussed the potential novel targeted therapies aimed at modulating the EIME in psoriasis. This comprehensive examination sheds light on the intricate underlying immune mechanisms and provides insights into potential therapeutic avenues of immune-mediated inflammatory diseases.

Methotrexate and electrostimulation cooperate to alleviate the relapse of psoriasiform skin inflammation by suppressing memory T cells

Methotrexate (MTX) is an immunosuppressant used to treat autoimmune diseases, including psoriasis. However, like other immunosuppressants, MTX alone does not prevent their recurrence. Electrostimulation (ES) has been utilized to treat some inflammatory disorders without any major side-effect. But it remains unknown if ES alone, or together with MTX, ameliorates autoimmune disease relapse: a sticky medical problem. In particular, the mechanisms underlying ES action remain unclear. The objective of this study was to determine an impact of ES and/or MTX on psoriasis relapse and their potential cooperation. We found that regional ES, but not MTX, ameliorated psoriasiform skin inflammation recurrence. Interestingly, treatment with both MTX and ES further prevented psoriasis recurrence compared to ES alone. Moreover, ES downregulated potassium channel Kv1.3 on T-cells and reduced CD4+/CD8+ effector memory (TEM) and CD8+ skin-resident memory T (TRM) cells, while ES plus MTX further decreased CD8+ TEM/TRM cells compared to ES alone. However, ES failed to further attenuate psoriasis recurrence or suppress T cell memory in Kv1.3-deficient mice, whereas lack of Kv1.3 itself ameliorated psoriasis relapse by shrinking T cell memory pool. Importantly, ES moderately inhibited T-cell proliferation in vitro. ES also reduced human CD8+ TRM cells and attenuated human skin lesions in humanized mice grafted with lesional skin from patients with recurrent psoriasis, with an enhanced efficacy in mice treated with both ES and MTX. Thus, ES and MTX cooperated to prevent psoriasis relapse by reducing T-cell memory via targeting potassium channel Kv1.3. Our studies may be implicated for treating human psoriasis.

Neutrophil recruitment by CD4 tissue-resident memory T cells induces chronic recurrent inflammation in atopic dermatitis

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory skin disease that continues to impose significant physical, mental, and economic burdens on patients. Recent research has suggested the significant role of tissue-resident memory (TRM) cells in AD. However, the precise role and mechanisms of action of TRM cells in AD remain unclear. A deeper understanding of the involvement of TRM cells in AD will unveil promising pathways for future innovative therapeutic strategies.

METHODS

To investigate the involvement of TRM cells in AD, we used diverse mouse models and employed experimental techniques to manipulate cell formation and depletion. We assessed the inflammatory response by analyzing mouse ear phenotype, measuring ear thickness, and performing hematoxylin and eosin staining. Flow cytometry and immunofluorescence staining were used to identify different cell types and evaluate changes in cell quantity. Additionally, we used qPCR to analyze gene expression of relevant chemokines and cytokines.

RESULTS

Our study revealed the presence of TRM cells in the skin after exposure to calcipotriol. After a 24-h re-challenge, we observed substantial neutrophil infiltration into the previously irritated skin. Neutrophil depletion prior to re-challenge effectively prevented early flare-up responses during AD recurrence. Furthermore, we demonstrate that CD4+TRM cells upregulate expression of cytokines INF-γ and TNF-α, which may induce the expression of CXCL1, thereby recruiting neutrophils and contributing to the chronic recurrent inflammation observed in AD.

CONCLUSIONS

We have established a novel, chronic recurrent mouse model for investigating TRM cells in AD. Our findings demonstrate that CD4+TRM cells in the skin mediate early flare-up response during AD recurrence and influence the chronic recurrent inflammation of AD by recruiting neutrophils. Targeting CD4+TRM cells may represent a promising approach for the treatment of chronic recurrent inflammation in AD.

Novel Bis-Artemisinin-Phloroglucinol hybrid molecules with dual anticancer and immunomodulatory Activities: Synthesis and evaluation

Bis-(10-deoxydihydroartemisinin)-phloroglucinol (9), has been synthesized in a one-step reaction and has demonstrated strong inhibition to cancer cell proliferation and immunosuppressive activity. The structure modification of the compound reduced its cytotoxicity, and among the analogs, bis-(10-deoxydihydroartemisinin)-phloroglucinol phenyl decanoate (16) showed significant reduction of ear swelling in a mouse model for DNFB-induced delayed-type hypersensitivity without observable toxicity in a dose-dependent manner.

Are Antimicrobial Peptides a 21st-Century Solution for Atopic Dermatitis?

Atopic dermatitis (AD) is a chronic inflammatory skin disorder that is the result of various environmental, bacterial and genetic stimuli, which culminate in the disruption of the skin's barrier function. Characterized by highly pruritic skin lesions, xerosis and an array of comorbidities among which skin infections are the most common, this condition results in both a significant loss of quality of life and in the need for life-long treatments (e.g., corticosteroids, monoclonal antibodies and regular antibiotic intake), all of which may have harmful secondary effects. This, in conjunction with AD's rising prevalence, made the development of alternative treatment strategies the focus of both the scientific community and the pharmaceutical industry. Given their potential to both manage the skin microbiome, fight infections and even modulate the local immune response, the use of antimicrobial peptides (AMPs) from more diverse origins has become one of the most promising alternative solutions for AD management, with some being already used with some success towards this end. However, their production and use also exhibit some limitations. The current work seeks to compile the available information and provide a better understanding of the state of the art in the understanding of AMPs' true potential in addressing AD.

Therapeutical Utilization and Repurposing of Artemisinin and Its Derivatives: A Narrative Review

Artemisinin (ART) and its derivatives have great therapeutical utility as antimalarials and can be repurposed for other indications, such as viral infections, autoimmune diseases, and cancer. This review presents a comprehensive overview of the therapeutic effects of ART-based drugs, beyond their antimalarial effects. This review also summarizes the information on their repurposing in other pathologies, with the hope that it will guide the future optimization of the use of ART-based drugs and of the treatment strategies for the listed diseases. By reviewing related literature, ART extraction and structure as well as the synthesis and structure of its derivatives are presented. Subsequently, the traditional roles of ART and its derivatives against malaria are reviewed, including antimalarial mechanism and occurrence of antimalarial resistance. Finally, the potential of ART and its derivatives to be repurposed for the treatment of other diseases are summarized. The great repurposing potential of ART and its derivatives may be useful for the control of emerging diseases with corresponding pathologies, and future research should be directed toward the synthesis of more effective derivatives or better combinations.

Effects and mechanisms of Chinese herbal medicine on IgA nephropathy

BACKGROUND

Immunoglobulin A nephropathy (IgAN), is the main cause of end-stage renal disease, that causes serious physical and psychological burden to patients worldwide. Some traditional treatment measures, such as blocking the renin-angiotensin-aldosterone system, controlling blood pressure, and following a low-protein diet, may not achieve satisfactory results. Therefore, more effective and safe therapies for IgAN are urgently needed.

PURPOSE

The aim of this review is to summarize the clinical efficacy of Chinese herbal medicines (CHMs) and their active ingredients in the treatment and management of IgAN based on the results of clinical trials, systematic reviews, and meta-analyses, to fully understand the advantages and perspectives of CHMs in the treatment of IgAN.

STUDY DESIGN AND METHODS

For this review, the following electronic databases were consulted: PubMed, ResearchGate, Science Direct, Web of Science, Chinese National Knowledge Infrastructure and Wanfang Data, "IgA nephropathy," "traditional Chinese medicine," "Chinese herbal medicine," "herb," "mechanism," "Meta-analysis," "systematic review," "RCT" and their combinations were the keywords to search the relevant literature. Data were collected from 1990 to 2022.

RESULTS

This review found that the active ingredients of CHMs commonly act on multiple signaling pathways in the clinical treatment of IgAN, mainly with antioxidant, anti-inflammatory and anti-fibrosis effects, and regulation of autophagy.

CONCLUSION

Compared with the single-target therapy of modern medicine, CHMs can regulate the corresponding pathways from the aspects of anti-inflammation, anti-oxidation, anti-fibrosis and autophagy to play a multi-target treatment of IgAN through syndrome differentiation and treatment, which has good clinical efficacy and can be used as the first choice or alternative therapy for IgAN treatment. This review provides evidence and research direction for a comprehensive clinical understanding of the protective effect of Chinese herbal medicine on IgAN.

Dihydroartemisinin-ursodeoxycholic acid conjugate is a potential treatment agent for inflammatory bowel disease

BACKGROUND

A novel artemisinin derivative, dihydroartemisinin-ursodeoxycholic acid conjugate (4), was found to exhibit strong immunosuppressive activity. Various methods were used to evaluate the immunosuppressive activity and mechanism of action of the compound to explore its potential applications.

METHODS

T cell proliferation, mixed lymphocyte reaction (MLR), and Th1/Th17 differentiation assays were used to evaluate the immunosuppressive activity of the compound. Differentially expressed genes from RNA sequencing were analysed with Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, while enriched signalling pathways were further validated by western blotting (WB). In vivo efficacy was validated with delayed-type hypersensitivity (DTH) mouse models and dextran sodium sulphate (DSS)-induced inflammatory bowel disease (IBD) mouse model.

RESULTS

Compound 4 inhibited concanavalin A -induced mouse splenic T cell proliferation (IC₅₀ = 15 nM) and anti-CD3/CD28-induced human primary T cell proliferation (IC₅₀ = 30 nM) while also reducing the secretion of hIFN-γ. Compound 4 exhibited similar inhibitory activity in MLR assay. Compound 4 dose-dependently inhibited human Th1/Th17 differentiation. The KEGG pathway enrichment analysis indicated that the genes related to T cell activation signalling pathways PI3K-AKT, MAPK, and NF-κB were significantly enriched. WB confirmed that compound 4 inhibited the AKT/MAPK and NF-κB signalling pathways. Compound 4 dose-dependently inhibited ear and foot pad swelling in DTH mouse models. In the DSS-induced IBD mouse model, compound 4 significantly decreased the disease activity index and colon density, and inhibited splenomegaly of the mice.

CONCLUSION

The in vitro and in vivo results indicated that compound 4 has the potential to be developed into an anti-IBD drug.

Celastrol inhibits store operated calcium entry and suppresses psoriasis

Introduction: Psoriasis is an inflammatory autoimmune skin disease that is hard to cure and prone to relapse. Currently available global immunosuppressive agents for psoriasis may cause severe side effects, thus it is crucial to identify new therapeutic reagents and druggable signaling pathways for psoriasis. Methods: To check the effects of SOCE inhibitors on psoriasis, we used animal models, biochemical approaches, together with various imaging techniques, including calcium, confocal and FRET imaging. Results and discussion: Store operated calcium (Ca²⁺) entry (SOCE), mediated by STIM1 and Orai1, is crucial for the function of keratinocytes and immune cells, the two major players in psoriasis. Here we showed that a natural compound celastrol is a novel SOCE inhibitor, and it ameliorated the skin lesion and reduced PASI scores in imiquimod-induced psoriasis-like mice. Celastrol dose- and time-dependently inhibited SOCE in HEK cells and HaCaT cells, a keratinocyte cell line. Mechanistically, celastrol inhibited SOCE via its actions both on STIM1 and Orai1. It inhibited Ca²⁺ entry through constitutively-active Orai1 mutants independent of STIM1. Rather than blocking the conformational switch and oligomerization of STIM1 during SOCE activation, celastrol diminished the transition from oligomerized STIM1 into aggregates, thus locking STIM1 in a partially active state. As a result, it abolished the functional coupling between STIM1 and Orai1, diminishing SOCE signals. Overall, our findings identified a new SOCE inhibitor celastrol that suppresses psoriasis, suggesting that SOCE pathway may serve as a new druggable target for treating psoriasis.

Effects of natural products on skin inflammation caused by abnormal hormones secreted by the adrenal gland

The cortex of adrenal gland produces glucocorticoid, mineralocorticoid, and androgen. The medulla of adrenal gland secrets catecholamines. These hormones play an important role in regulating blood pressure, metabolism, and homeostasis of glucose or electrolytes. Hypersecretion or hyposecretion by the adrenal gland will cause a complex cascade of hormone effects and lead to diseases, including Addison's disease, Cushing's syndrome, and congenital adrenal cortical hyperplasia. Skin is the largest organ of body. It provides protection and acts as a barrier against external damage factors like infectious organisms, chemicals, and allergens. Endocrinologic disorders often induce cutaneous abnormalities. According to the previous evidences, natural products have the potential properties for attenuating skin disorders and improving dermatologic symptoms by inhibiting inflammation through MAPK or PI3K/AKT-dependent NF-κB pathways. The natural products may also promote skin wound healing by inhibiting the production of matrix metalloproteinase-9. We systematically searched the relevant articles from databases, including PubMed, Embase, and Cochrane library databases, to review the effects of natural products on skin disorders. This article summarized the effects of natural products on skin inflammation caused by abnormal hormone secreted by adrenal gland. And the published papers indicated that natural products might be a potential source for treating skin diseases.

Synergetic delivery of artesunate and isosorbide 5-mononitrate with reduction-sensitive polymer nanoparticles for ovarian cancer chemotherapy

Ovarian cancer is a highly fatal gynecologic malignancy worldwide. Chemotherapy remains the primary modality both for primary and maintenance treatments of ovarian cancer. However, the progress in developing chemotherapeutic agents for ovarian cancer has been slow in the past 20 years. Thus, new and effective chemotherapeutic drugs are urgently needed for ovarian cancer treatment. A reduction-responsive synergetic delivery strategy (PSSP@ART-ISMN) with co-delivery of artesunate and isosorbide 5-mononitrate was investigated in this research study. PSSP@ART-ISMN had various effects on tumor cells, such as (i) inducing the production of reactive oxygen species (ROS), which contributes to mitochondrial damage; (ii) providing nitric oxide and ROS for the tumor cells, which further react to generate highly toxic reactive nitrogen species (RNS) and cause DNA damage; and (iii) arresting cell cycle at the G0/G1 phase and inducing apoptosis. PSSP@ART-ISMN also demonstrated excellent antitumor activity with good biocompatibility in vivo. Taken together, the results of this work provide a potential delivery strategy for chemotherapy in ovarian cancer.

Dihydroartemisinin regulates immune cell heterogeneity by triggering a cascade reaction of CDK and MAPK phosphorylation

Artemisinin (ART) and dihydroartemisinin (DHA), apart from their profound anti-malaria effect, can also beneficially modulate the host immune system; however, the underlying molecular mechanisms remain unclear. Here, we report that DHA selectively induced T-cell activation, with an increased proportion of Ki67⁺CD4⁺ T cells, CD25⁺CD4⁺ T cells, interferon (IFN)-γ-producing CD8⁺ T cells, Brdu⁺ CD8⁺ T cells and neutrophils, which was found to enhance cellular immunity to experimental malaria and overcome immunosuppression in mice. We further revealed that DHA upregulated the expression of cell proliferation-associated proteins by promoting the phosphorylation of mitogen-activated protein kinase (MAPK), cyclin-dependent kinases (CDKs), and activator protein 1 in the spleen. This study is the first to provide robust evidence that DHA selectively induced the expansion of subsets of splenic T cells through phosphorylated CDKs and MAPK to enhance cellular immune responses under non-pathological or pathological conditions. The data significantly deepened our knowledge in the mechanism underlying DHA-mediated immunomodulation.

Dihydroarteannuin Ameliorates Collagen-Induced Arthritis Via Inhibiting B Cell Activation by Activating the FcγRIIb/Lyn/SHP-1 Pathway

Background: Dihydroarteannuin (DHA), which is extracted from the traditional Chinese herb Artemisia annua L, exhibits potent immunosuppressive activity in rheumatoid arthritis (RA). Strong evidence indicates that B cells act as an essential factor in the pathogenesis of RA, but research on the immunosuppressive function of DHA in regulating B cells is limited. Objective: To investigate the modulatory effects of DHA on joint destruction, proinflammatory cytokine production, activation, apoptosis and proliferation of B cells and to explore the possible associated mechanism in RA treatment. Methods: Collagen-induced arthritis (CIA) model was established. Weight and joint oedema were record weekly, and joint damage was detected by micro-CT scan. Human Burkitt B lymphoma cells lacking endogenous Fc gamma receptor b (FcγRIIb) gene were transfected with a 232Thr loss-of-function mutant to construct a mutant cell model ST486. The proliferation of ST486 cells was assessed with Cell Counting Kit-8. Apoptosis and activation were tested by flow cytometry. The effects of DHA on the activation of FcγRIIb, protein tyrosine kinases (Lyn), and SH2-containing tyrosine phosphatase-1 (SHP-1) signaling pathways were determined by western blotting. Results: In comparison to model group, bone volume/tissue volume (BV/TV) and bone mineral density (BMD) were increased, whereas joint oedema was decreased in both of the DHA and MTX group. The mRNA and protein expression levels of Interleukin-6 (IL-6) and Tumor necrosis factor-alpha (TNF-α) were decreased after treatment with DHA. In addition, DHA treatment promoted the apoptosis, inhibited the activation and proliferation of ST486 cells. Furthermore, the protein expression levels of FcγRIIb, SHP-1, and Lyn were increased after treatment with DHA. Moreover, the expression of phosphorylated CD19 was also inhibited by DHA. Conclusion: We provide the first evidence that DHA may alleviate collagen-induced arthritis by activating the FcγRIIb/Lyn/SHP-1 signaling pathway in B cell, indicating that DHA is a novel and valuable candidate for RA therapy.

Suppression of NLRP3 Inflammasome by Dihydroarteannuin via the HIF-1α and JAK3/STAT3 Signaling Pathway Contributes to Attenuation of Collagen-Induced Arthritis in Mice

Dihydroarteannuin (DHA), the primary element of artemisinin extracted from the traditional Chinese herb Artemisia annua L., has been used in malaria treatment for a long time. Recently, many studies have indicated that DHA also exhibits potent anti-rheumatoid arthritis (RA) activity. In this study, collagen-induced arthritis (CIA) in DBA/1J mice and inflammatory model in THP-1 cells were established to evaluate the modulatory effects of DHA on joint destruction and to explore the underlying mechanisms. Our results showed that DHA decreased the serum levels of IL-1β and IL-6, alleviated paw oedema, and reduced bone destruction in DBA/1J mice with CIA. Further exploration with the inflammatory model in THP-1 cells indicated that DHA reduced the protein expression of hypoxia‐inducible factor (HIF)‐1α and the phosphorylation in Janus kinase (JAK) 3 and signal transducer and activator of transcription (STAT) 3 protein, which resulted in a decrease in NOD-like receptor protein (NLRP) 3 expression and interleukin (IL)-1β release. Consequentially, the inflammatory activation in THP-1 cells was inhibited. Therefore, we concluded that DHA efficiently alleviated the inflammation and arthritic symptoms in CIA mice and downregulated inflammation in part by inhibiting NLRP3 expression via the HIF‐1α and JAK3/STAT3 signaling pathway. Thus, DHA may be considered as a potential therapeutic agent in RA treatment.

Dihydroartemisinin alleviates steatosis and inflammation in nonalcoholic steatohepatitis by decreasing endoplasmic reticulum stress and oxidative stress

Nonalcoholic steatohepatitis (NASH) is a severely inflammatory subtype of nonalcoholic fatty liver. Endoplasmic reticulum stress (ERS) and oxidative stress (OS) cause metabolic abnormalities, promote liver steatosis and inflammation, and are central to the development of NASH. Dihydroartemisinin (DHA) is a compound extracted from Artemisia annua that is often used in the treatment of malaria. Recent studies have shown that DHA also has a wide range of pharmacological effects, acting on various organs throughout the body to exert anti-inflammatory, antioxidant, and anti-fibrotic effects. In this study, we demonstrated in vitro that the anti-inflammatory effect of DHA is effective against NASH and reduces liver steatosis. DHA treatment decreased the synthesis of lipids, such as cholesterol and free fatty acids, and the expression of nuclear factor kappa-B. This is accomplished by inhibiting the unfolded protein response and reducing the production of reactive oxygen species, thereby inhibiting OS and ERS. This study reveals DHA's therapeutic effect and potential mechanism in NASH, implying that DHA could be a new and promising candidate for NASH therapy.

Dihydroartemisinin beneficially regulates splenic immune cell heterogeneity through the SOD3-JNK-AP-1 axis

The immunomodulatory potential of dihydroartemisinin (DHA) has recently been highlighted; however, the potential mechanism remains to be clarified. Single-cell RNA sequencing was explored in combination with cellular and biochemical approaches to elucidate the immunomodulatory mechanisms of DHA. In this study, we found that DHA induced both spleen enlargement and rearrangement of splenic immune cell subsets in mice. It was revealed that DHA promoted the reversible expansion of effective regulatory T cells and interferon-γ⁺ cytotoxic CD8⁺ T cells in the spleen via induction of superoxide dismutase 3 (SOD3) expression and increased phosphorylation of c-Jun N-terminal kinases (JNK) and its downstream activator protein 1 (AP-1) transcription factors. Further, SOD3 knockout mice were resistant to the regulatory effect of DHA. Thus, DHA, through the activation of the SOD3-JNK-AP-1 axis, beneficially regulated immune cell heterogeneity and splenic immune cell homeostasis to treat autoimmune diseases.

Dihydroartemisinin-Transferrin Adducts Enhance TRAIL-Induced Apoptosis in Triple-Negative Breast Cancer in a P53-Independent and ROS-Dependent Manner

Triple-negative breast cancer (TNBC) is a highly aggressive breast cancer subtype independent of estrogen receptor, progesterone receptor, or human epidermal growth factor receptor 2. It has a poor prognosis and high recurrence. Due to its limited treatment options in the clinic, novel therapies are urgently needed. Single treatment with the death receptor ligand TRAIL was shown to be poorly effective. Recently, we have shown that artemisinin derivatives enhance TRAIL-induced apoptosis in colon cancer cells. Here, we utilized transferrin (TF) to enhance the effectiveness of dihydroartemisinin (DHA) in inducing cell death in TNBC cell lines (MDA-MB-231, MDA-MB-436, MDA-MB-468 and BT549). We found that the combination of DHA-TF and the death receptor 5-specific TRAIL variant DHER leads to an increase in DR5 expression in all four TNBC cell lines, while higher cytotoxicity was observed in MDA-MB-231, and MDA-MB-436. All the data point to the finding that DHA-TF stimulates cell death in TNBC cells, while the combination of DHA-TF with TRAIL variants will trigger more cell death in TRAIL-sensitive cells. Overall, DHA-TF in combination with TRAIL variants represents a potential novel combination therapy for triple-negative breast cancer.

Dihydroartemisinin Exerts Antifibrotic and Anti-Inflammatory Effects in Graves' Ophthalmopathy by Targeting Orbital Fibroblasts

Graves' ophthalmopathy (GO) is a common orbital disease that threatens visual function and appearance. Orbital fibroblasts (OFs) are considered key target and effector cells in GO. In addition, hyaluronan (HA) production, inflammation, and orbital fibrosis are intimately linked to the pathogenesis of GO. In this study, we explored the therapeutic effects of dihydroartemisinin (DHA), an antimalarial drug, on GO-derived, primary OFs. CCK8 and EdU assays were applied to evaluate the antiproliferative effect of DHA on OFs. Wound healing assays were conducted to assess OF migration capacity, while qRT-PCR, western blotting, ELISA, and immunofluorescence were used to determine the expression of fibrosis-related and pro-inflammatory markers in these cells. Moreover, RNA sequencing was conducted to identify differentially expressed genes (DEGs) in DHA-treated OFs, and Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of DEGs was performed to explore potential mechanisms mediating the antifibrotic effect of DHA on GO-derived OFs. Results showed that DHA dose-dependently inhibited OF proliferation and downregulated, at the mRNA and protein levels, TGF-β1-induced expression of fibrosis markers, including alpha smooth muscle actin (α-SMA) and connective tissue growth factor (CTGF). Furthermore, DHA inhibited TGF-β1 induced phosphorylation of extracellular signal-regulated protein kinase 1/2 (ERK1/2) and signal transducer and activator of transcription 3 (STAT3), which suggested that DHA exerted antifibrotic effects via suppression of the ERK and STAT3 signaling pathways. In addition, DHA suppressed the expression of pro-inflammatory cytokines and chemokines, including IL-6, IL-8, CXCL-1, MCP-1, and ICAM-1, and attenuated HA production induced by IL-1β in GO-derived OFs. In conclusion, our study provides first-time evidence that DHA may significantly alleviate pathogenic manifestations of GO by inhibiting proliferation, fibrosis- and inflammation-related gene expression, and HA production in OFs. These data suggest that DHA may be a promising candidate drug for treatment of GO.

Dihydroartemisinin targets fibroblast growth factor receptor 1 (FGFR1) to inhibit interleukin 17A (IL-17A)-induced hyperproliferation and inflammation of keratinocytes

Psoriasis is a common chronic immune-mediated disease that often has a serious negative impact on the physical and mental health of patients. Dihydroartemisinin (DHA) is a drug with anti-fibrotic and anti-inflammatory effects that may be involved in the autoimmune regulation of immune diseases. However, the effects of DHA on psoriasis have not been reported comprehensively. Therefore, the aim of this study was to investigate the effect of DHA on abnormal proliferation and inflammation of epidermal keratinocyte cells in psoriasis and its mechanism of action. IL-17A-induced human epidermal keratin-forming cells (HaCaT) were used as a model. And after induction exposure to different concentrations of DHA, CCK-8, EDU staining, wound healing and Western blotting were performed to assess cell viability, proliferation, migration, differentiation and inflammatory factors, respectively. Subsequently, agonists of fibroblast growth factor receptor 1 (FGFR1) were added and the above experiments were repeated. The results showed that DHA obviously inhibited IL-17A-induced hyperproliferation, migration and expression of inflammatory factors in HaCaT cells. Furthermore, FGFR1 was highly expressed in IL-17A-induced HaCaT cells, and DHA inhibited its expression. However, the inhibitory effect of DHA on IL-17A-induced HaCaT cells was reversed after the addition of FGFR1 agonist. In conclusion, DHA could inhibit IL-17A-induced hyperproliferation and inflammation of keratinocytes by targeting FGFR1, which also provided a new target for the treatment of psoriasis.

Dihydroartemisinin Suppresses the Tumorigenesis and Cycle Progression of Colorectal Cancer by Targeting CDK1/CCNB1/PLK1 Signaling

Dihydroartemisinin (DHA), a well-known antimalarial drug, has been widely investigated for its antitumor effects in multiple malignancies. However, its effects and regulatory mechanisms in colorectal cancer (CRC) are still unproved. In this study, in vitro experiments including CCK8, EdU, Transwell, and flow cytometry analyses and an in vivo tumorigenesis model were conducted to assess the effects of DHA on the bio-behaviors of CRC cells. Additionally, RNA-seq combined with gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses was used to obtain the targets of DHA, and these were verified by molecular docking, qRT-PCR, and Western blotting. As a result, we found that DHA significantly suppressed the proliferation, DNA synthesis, and invasive capabilities and induced cell apoptosis and cell cycle arrest in HCT116, DLD1, and RKO cells in vitro and in vivo. Further analyses indicated that the targets of DHA were predominantly enriched in cell cycle-associated pathways, including CDK1, CCNB1, and PLK1; and DHA could bind with the CDK1/CCNB1 complex and inhibit the activation of CDK1/CCNB1/PLK1 signaling. Moreover, cucurbitacin E, a specific inhibitor of the CDK1/CCNB1 axis, enhanced the inhibitory effects of DHA on DNA synthesis and colony formation in HCT116 and DLD1 cells. In short, DHA could suppress the tumorigenesis and cycle progression of CRC cells by targeting CDK1/CCNB1/PLK1 signaling.

Dihydroartemisinin: A Potential Drug for the Treatment of Malignancies and Inflammatory Diseases

Dihydroartemisinin (DHA) has been globally recognized for its efficacy and safety in the clinical treatment of malaria for decades. Recently, it has been found that DHA inhibits malignant tumor growth and regulates immune system function in addition to anti-malaria. In parasites and tumors, DHA causes severe oxidative stress by inducing excessive reactive oxygen species production. DHA also kills tumor cells by inducing programmed cell death, blocking cell cycle and enhancing anti-tumor immunity. In addition, DHA inhibits inflammation by reducing the inflammatory cells infiltration and suppressing the production of pro-inflammatory cytokines. Further, genomics, proteomics, metabolomics and network pharmacology of DHA therapy provide the basis for elucidating the pharmacological effects of DHA. This review provides a summary of the recent research progress of DHA in anti-tumor, inhibition of inflammatory diseases and the relevant pharmacological mechanisms. With further research of DHA, it is likely that DHA will become an alternative therapy in the clinical treatment of malignant tumors and inflammatory diseases.

Immunoregulation by Artemisinin and Its Derivatives: A New Role for Old Antimalarial Drugs

Artemisinin and its derivatives (ARTs) are known as conventional antimalarial drugs with clinical safety and efficacy. Youyou Tu was awarded a Nobel Prize in Physiology and Medicine due to her discovery of artemisinin and its therapeutic effects on malaria. Apart from antimalarial effects, mounting evidence has demonstrated that ARTs exert therapeutic effects on inflammation and autoimmune disorders because of their anti-inflammatory and immunoregulatory properties. In this aspect, tremendous progress has been made during the past five to seven years. Therefore, the present review summarizes recent studies that have explored the anti-inflammatory and immunomodulatory effects of ARTs on autoimmune diseases and transplant rejection. In this review, we also discuss the cellular and molecular mechanisms underlying the immunomodulatory effects of ARTs. Recent preclinical studies will help lay the groundwork for clinical trials using ARTs to treat various immune-based disorders, especially autoimmune diseases.

The STING antagonist H-151 ameliorates psoriasis via suppression of STING/NF-κB-mediated inflammation

BACKGROUND AND PURPOSE

Psoriasis is a chronic inflammatory skin disease associated with both innate and adaptive immune responses. The stimulator of interferon genes (STING) protein engages in sensing of cytosolic DNA to initiate dsDNA-driven immune responses. In vitro and in vivo anti-psoriasis effects of STING antagonist H-151 were explored.

EXPERIMENTAL APPROACH

We analysed the gene expression profile of STING and related downstream targets in the skin samples of healthy people and psoriasis patients from the GEO database. Cellular inhibitory activity of H-151 on STING pathway was confirmed via qPCR and western blotting. The preventive effect of topical application of H-151 on imiquimod-induced psoriatic mice was examined through histological, immunohistochemical, immunofluorescent, flow cytometric analysis, ELISA Kits and other approaches. Preliminary mechanistic studies were also performed.

KEY RESULTS

Gene expressions of STING and its downstream target were up-regulated in lesional skin samples from psoriasis patients. Topical administration of H-151 attenuated the skin lesions in imiquimod-induced psoriatic mouse model, while the secretion of pro-inflammatory cytokines (IL-17, IL-23 and IL-6), infiltration of M1 macrophages and differentiation of Th17 cells were significantly suppressed by H-151 treatment. Mechanistically, H-151 inhibited STING/NF-κB signalling in both keratinocytes and immune cells.

CONCLUSION AND IMPLICATIONS

H-151 displayed anti-inflammatory activity in both keratinocytes and immune cells, and decreased the severity of psoriatic response in vivo. Inhibition of STING signalling pathway may represent a novel therapeutic approach to psoriasis and related complications.

Unconventional Therapy with IgY in a Psoriatic Mouse Model Targeting Gut Microbiome

Psoriasis has a multifactorial pathogenesis and recently it was shown that alterations in the skin and intestinal microbiome are involved in the pathogenesis of psoriasis. Therefore, microbiome restoration becomes a promising preventive/therapy strategy in psoriasis. In our pre-clinical study design using a mice model of induced psoriatic dermatitis (Ps) we have tested the proof-of-concept that IgY raised against pathological human bacteria resistant to antibiotics can alleviate psoriatic lesions and restore deregulated immune cell parameters. Besides clinical evaluation of the mice and histology of the developed psoriatic lesions, cellular immune parameters were monitored. Immune cells populations/subpopulations from peripheral blood and spleen cell suspensions that follow the clinical improvement were assessed using flow cytometry. We have quantified T lymphocytes (CD3ε⁺) with T-helper (CD4⁺CD8^-) and T-suppressor/cytotoxic (CD8a⁺CD4^-) subsets, B lymphocytes (CD3ε^-CD19⁺) and NK cells (CD3ε^-NK1.1⁺). Improved clinical evolution of the induced Ps along with the restoration of immune cells parameters were obtained when orally IgY was administered. We pin-point that IgY specific compound can be used as a possible pre-biotic-like alternative adjuvant in psoriasis.

Tissue-Resident Memory T Cells in Skin Diseases: A Systematic Review

In health, the non-recirculating nature and long-term persistence of tissue-resident memory T cells (TRMs) in tissues protects against invading pathogens. In disease, pathogenic TRMs contribute to the recurring traits of many skin diseases. We aimed to conduct a systematic literature review on the current understanding of the role of TRMs in skin diseases and identify gaps as well as future research paths. EMBASE, PubMed, SCOPUS, Web of Science, Clinicaltrials.gov and WHO Trials Registry were searched systematically for relevant studies from their inception to October 2020. Included studies were reviewed independently by two authors. This study was conducted in accordance with the PRISMA-S guidelines. This protocol was registered with the PROSPERO database (ref: CRD42020206416). We identified 96 studies meeting the inclusion criteria. TRMs have mostly been investigated in murine skin and in relation to infectious skin diseases. Pathogenic TRMs have been characterized in various skin diseases including psoriasis, vitiligo and cutaneous T-cell lymphoma. Studies are needed to discover biomarkers that may delineate TRMs poised for pathogenic activity in skin diseases and establish to which extent TRMs are contingent on the local skin microenvironment. Additionally, future studies may investigate the effects of current treatments on the persistence of pathogenic TRMs in human skin.

TPGS assists the percutaneous administration of curcumin and glycyrrhetinic acid coloaded functionalized ethosomes for the synergistic treatment of psoriasis

Combined therapy with anti-inflammatory drugs is preferred for the topical treatment of psoriasis, but the codelivery of drugs is restricted due to the lack of a suitable delivery system. Ethosomes with excellenttransdermal propertiesare perfect as carriers for hyperplastic skin. Therefore, glycyrrhetinic acid-D-α-tocopherol acid polyethylene glycol succinate (GA-TPGS) was synthesized, which prevented the inflammation and lipid peroxidation damage, thus effectively stabilizing the psoriasis. Then GA-TPGS was surface-modified on the curcumin (Cur) loaded ethosomes to construct curcumin-loaded GA-TPGS-modified multifunctional ethosomes (Cur@GA-TPGS-ES), exerting synergistic treatment for psoriasis. Using an interleukin-6-induced cell model, we found that Cur@GA-TPGS-ES displayed desirable suppression of inflammation response and oxidative stress damage. Compared with the ethanol solution, the percutaneous penetration rates of Cur and GA in Cur@GA-TPGS-ES were superior. In vivo microdialysis revealed similar results, suggesting an increase of transcutaneous absorption in Cur@GA-TPGS-ES. Fluorescence staining revealed that the cellular uptake and skin distribution were distinctly enhanced with the delivery by Cur@GA-TPGS-ES. After topical administration to imiquimod-induced psoriatic mice, the Cur@GA-TPGS-ES group showed powerful treatment from inflammatory infiltration inhibition of Cur, glucocorticoid-like effects of GA and anti-lipid peroxidation of TPGS. Overall, GA-TPGS mediated ethosomes possess more advantageous transdermal properties and synergistic antipsoriatic efficacy.

Metabolomic profiling reveals amino acid and carnitine alterations as metabolic signatures in psoriasis

High-throughput metabolite profiling provides the opportunity to reveal metabolic mechanisms and identify biomarkers. Psoriasis is an immune-mediated chronic inflammatory disease. However, the role of metabolism in psoriasis pathogenesis remains unclear. Methods: Plasma samples of individuals (45 psoriasis and 45 sex-, age-, and BMI-matched healthy controls) were collected. Non-targeted metabolomics and amino acid- or carnitine-targeted metabolomics were conducted, then, plasma samples of mice induced by imiquimod (IMQ) were subjected to the amino acid- and carnitine-targeted metabolomic profiling. Flow cytometry was used to study the effect of L-carnitine (LC(C0)) on IMQ-induced psoriatic inflammation. Results: Through the non-targeted metabolomics approach, we detected significantly altered amino acids and carnitines in psoriasis patients. Amino acid-targeted metabolomic profiling identified 37 amino acids altered in psoriasis, of these 23 were markedly upregulated, including essential amino acids (EAAs), and branched-chain amino acids (BCAAs), whereas glutamine, cysteine, and asparagine were significantly down-regulated. Carnitine-targeted metabolomic profiling identified 40 significantly altered carnitines, 14 of which included palmitoylcarnitine (C16) and were markedly downregulated in psoriasis, whereas hexanoylcarnitine (C6) and 3-OH-octadecenoylcarnitine (C18:1-OH) were significantly upregulated. Interestingly, glutamine, asparagine, and C16 levels were negatively correlated with the PASI score. Moreover, a higher abundance of LC(C0) was associated with markedly reduced IMQ-induced epidermal thickening and infiltration of Th17 cells in skin lesions, indicating LC(C0) supplementation as a potential therapy for psoriasis treatment. Conclusion: Our results suggested the metabolism of amino acids and carnitines are significantly altered in psoriasis, especially the metabolism of EAAs, BCAAs, and LC(C0), which may play key roles in the pathogenesis of psoriasis.

Resolvin D3 controls mouse and human TRPV1-positive neurons and preclinical progression of psoriasis

Rationale: Psoriasis is a chronic inflammatory disease caused by a complex interplay between the immune and nervous systems with recurrent scaly skin plaques, thickened stratum corneum, infiltration and activation of inflammatory cells, and itch. Despite an increasing availability of immune therapies, they often have adverse effects, high costs, and dissociated effects on inflammation and itch. Activation of sensory neurons innervating the skin and TRPV1 (transient receptor potential vanilloid 1) are emerging as critical components in the pathogenesis of psoriasis, but little is known about their endogenous inhibitors. Recent studies have demonstrated that resolvins, endogenous lipid mediators derived from omega-3 fatty acids, are potent inhibitors of TRP channels and may offer new therapies for psoriasis without known adverse effects. Methods: We used behavioral, electrophysiological and biochemical approaches to investigate the therapeutic effects of resolvin D3 (RvD3), a novel family member of resolvins, in a preclinical model of psoriasis consisting of repeated topical applications of imiquimod (IMQ) to murine skin, which provokes inflammatory lesions that resemble human psoriasis. Results: We report that RvD3 specifically reduced TRPV1-dependent acute pain and itch in mice. Mechanistically, RvD3 inhibited capsaicin-induced TRPV1 currents in dissociated dorsal root ganglion (DRG) neurons via the N-formyl peptide receptor 2 (i.e. ALX/FPR2), a G-protein coupled receptor. Single systemic administration of RvD3 (2.8 mg/kg) reversed itch after IMQ, and repeated administration largely prevented the development of both psoriasiform itch and skin inflammation with concomitant decreased in calcitonin gene-related peptide (CGRP) expression in DRG neurons. Accordingly, specific knockdown of CGRP in DRG was sufficient to prevent both psoriasiform itch and skin inflammation similar to the effects following RvD3 administration. Finally, we elevated the translational potential of this study by showing that RvD3 significantly inhibited capsaicin-induced TRPV1 activity and CGRP release in human DRG neurons. Conclusions: Our findings demonstrate a novel role for RvD3 in regulating TRPV1/CGRP in mouse and human DRG neurons and identify RvD3 and its neuronal pathways as novel therapeutic targets to treat psoriasis.