Liangxue Jiedu formula improves imiquimod-induced psoriasiform dermatitis with circadian desynchrony by regulating Th17 cell differentiation based on network pharmacological analysis.

ETHNOPHARMACOLOGICAL RELEVANCE: Liangxue Jiedu formula (LXJDF) is an effective traditional Chinese medicine (TCM) formula for treating psoriasis of blood-heat syndrome and has been used in clinics for decades. AIM OF THE STUDY: This study aimed to discover the mechanism of LXJDF in psoriasis and the circadian clock by network pharmacology and experimental studies. MATERIALS AND METHODS: The compounds of LXJDF were obtained from the TCMSP and BATMAN-TCM databases. The genes related to psoriasis and circadian rhythm/clock were identified by the OMIM and GeneCards databases. Then, target genes were integrated by Venn and analyzed by the String, CytoNCA, DAVID (GO and KEGG) databases, and the network was constructed using Cytoscape. Mice were raised under light disturbance for fourteen days. On the eighth day, mouse dorsal skin was shaved and smeared with 62.5 mg 5% imiquimod at 8:00 (ZT0) for six successive days. Mice were randomly divided into the model, LXJDF-H (49.2 g/kg·bw), LXJDF-L (24.6 g/kg·bw), and positive drug (dexamethasone) groups. Other mice were smeared with Vaseline under the normal light cycle as the control. The drug of each group was administered at 10:00 (ZT2) and 22:00 (ZT14). The skin lesions were observed, and PASI was scored daily. HE and immunofluorescence were used to measure pathological morphology. Th17 cytokines in serum and skin were measured by flow cytometry and qPCR. Circadian clock gene and protein expression levels were determined by qPCR and Western blotting. RESULTS: We found 34 potential targets of LXJDF in the treatment of psoriasis and circadian rhythm and confirmed their importance by topology analysis. KEGG pathway analysis revealed that the two major pathways were Th17 cell differentiation and the HIF-1 signaling pathway. At ZT2 and ZT14, LXJDF improved IMQ-induced light disturbance mouse skin lesions, including alleviating scales, erythema, and infiltration, reducing PASI, and inhibiting keratinocyte hyperproliferation and parakeratosis. LXJDF reduced IL-17A, IL-17F, TNF-α, and IL-6 in serum at ZT2 and increased IL-10 at ZT2 and ZT14. LXJDF downregulated the expression of IL-17A and IL-17F in skin. At ZT2, LXJDF significantly upregulated CLOCK and REV-ERBα expression and downregulated HIF-1α expression. At ZT14, LXJDF decreased HIF-1α and RORγt expression and significantly increased REV-ERBα expression. CONCLUSION: LXJDF improves psoriasis dermatitis with circadian rhythm disorders by regulating Th17 cell differentiation.

Tryptanthrin ameliorates imiquimod-induced psoriasis in mice by suppressing inflammation and oxidative stress via NF-κB/MAPK/Nrf2 pathways.

Nowadays, approximately 3% of the world's population suffers from psoriasis, an inflammatory dermatosis with high recurrence. Tryptanthrin (TRYP) is a natural alkaloid that possesses anti-inflammatory activities on multiple diseases. The present study aimed to unravel whether TRYP could relieve psoriasis and how it works. Imiquimod (IMQ)-induced psoriatic mouse models were administered saline (model), TRYP (25 and 100 mg/kg), or methotrexate (MTX, 1 mg/kg) and considered as the positive control. TNF-α-induced keratinocytes (HaCaT cells) with TRYP (0, 10, 20 and 50 nM) were used for in vitro verification. Psoriasis area severity index (PASI) and spleen index were evaluated. Th17 cell infiltration in both spleens and lymph nodes was detected by flow cytometry. The expression levels of inflammatory cytokines, glutathione (GSH), malondialdehyde (MDA) and catalase (CAT), as well as superoxide dismutase (SOD), were examined by ELISA, while the NF-κB/MAPK/Nrf2 pathways-related proteins were determined by western blot. TRYP significantly attenuated psoriatic skin lesions, increased GSH, SOD, and CAT levels, reduced spleen index, accumulation of MDA, the abundance of Th17 cells in both the spleen and lymph nodes, and secretion of inflammatory cytokines in IMQ-induced psoriatic mouse models. Mechanically, TRYP suppressed IMQ-activated NF-κB (IκB and p65), MAPK (JNK, ERK1/2, and p38), and activated Nrf2 signaling pathways. Similar alterations for inflammation and oxidative stress parameters and NF-κB/MAPK/Nrf2 pathways were also observed in TNF-α-treated HaCaT cells upon TRYP treatment. Our findings suggested TRYP is effective in protecting against inflammation and oxidative stress in psoriasis-like pathogenesis by modulating the NF-κB/MAPK/Nrf2 pathways.

Free Fatty Acid Receptor 4 (FFA4) Activation Ameliorates Imiquimod-Induced Psoriasis in Mice.

Dietary supplementation with n-3 polyunsaturated fatty acids (n-3 PUFA) has been used as an adjunct therapy for psoriasis due to its anti-inflammatory properties. Free fatty acid receptor 4 (FFA4 or GPR120) is a receptor-sensing n-3 PUFA. In the present study, we examined whether FFA4 acted as a therapeutic target for n-3 PUFA in psoriasis therapy. Experimentally, psoriasis-like skin lesions were induced by treatment with imiquimod for 6 consecutive days. A selective FFA4 agonist, Compound A (30 mg/kg), was used in FFA4 WT and FFA4 KO mice. Imiquimod-induced psoriasis-like skin lesions, which present as erythematous papules and plaques with silver scaling, as well as markedly elevated IL-17/IL-23 cytokine levels in skin tissues, were significantly suppressed by Compound A in FFA4 WT mice, but not in FFA4 KO mice. Enlarged lymph nodes and spleens, as well as imiquimod-induced, elevated IL-17/IL-23 cytokine levels, were also strongly suppressed by Compound A in FFA4 WT mice, but not in FFA4 KO mice. Imiquimod-induced increases in the CD4+IL-17A+ T cell population in lymph nodes and spleens were suppressed by Compound A treatment in FFA4 WT mice; however, this was not seen in FFA4 KO mice. Furthermore, compound A suppressed the differentiation of CD4+ naïve T cells from splenocytes into TH17 cells in an FFA4-dependent manner. In conclusion, we demonstrated that the activation of FFA4 ameliorates imiquimod-induced psoriasis, and the suppression of the differentiation of TH17 cells may partly contribute to its efficacy. Therefore, we suggest that FFA4 could be a therapeutic target for psoriasis therapy.

Total withanolides ameliorates imiquimod-induced psoriasis-like skin inflammation.

ETHNOPHARMACOLOGICAL RELEVANCE: Datura metel L. has been used as an anesthetic in clinic for more than 1800 years in China, and the main efficacy of D. metel L. flower is relieving asthma and cough, relieving spasm and relieving pain. From 1978 to 1980, Datura metel L. was used as an anesthetic agent and occasionally cured psoriasis patients during anesthesia clinically, and our group confirmed that the effective portion is total withanolides (YWS). Moreover, the new drug "Datura metel L. capsule" composed of YWS has since been approved and used for the treatment of more than 3,000 psoriasis patients, with efficacy and cure rates greater than 90% and 65%. However, the immunological mechanism has not been elucidated. AIM OF THE STUDY: Nowadays, although total withanolides from Datura metel L. have a better clinical efficacy in the treatment of psoriasis, there is a lack of overall understanding of the mechanism of their treatment, especially about some immune cells and proteins closely related to psoriasis and their relationship in executive function and biological significance. This study focused on investigating the mechanism of psoriasis treatment by YWS and determined the biochemical processes in the treatment of psoriasis based on Treg/Th17 axis cell-mediated bidirectional immunoregulatory functions, which provides an important scientific basis for understanding the mechanism underlying the treatment of psoriasis by YWS. MATERIALS AND METHODS: The effects of YWS on the lesion pathology of IMQ-induced psoriasis mice and the underlying molecular mechanism were assessed directly using HE staining, the PASI score and the animal body mass. We also investigated the effects of YWS on the Treg/Th17 axis and their critical functions in psoriasis pathogenesis via molecular biological methods. Finally, we performed differential proteomics analysis on skin in IMQ-induced psoriasis mice to clarify the effect of YWS by incorporates mass spectrometry-bioinformatics and annotated the functions and pathways associated with the differential proteins through GO enrichment, KEGG pathway analysis and PPI networks analysis, respectively. RESULTS: YWS regulated the imbalance of the Treg/Th17 axis. And proteomic analysis showed that YWS up-regulated 46 and down-regulated 37 proteins. According to the bioinformatics analysis, the improvement of Treg/Th17 imbalance may be the key immunological mechanism of YWS in the treatment of psoriasis by up-regulating the butyrate metabolism pathway, down-regulating leukocyte migration, inhibiting the phagocytic function of natural killer cells, suppressing osteoclast differentiation and interfering with chemokine activity, and the critical proteins involved are Lyn, HMGCS2, ABAT, ITGß2, PRKCß, MMP9, NCF1, JUNß, and Hck. CONCLUSION: This research clarified that the improvement of the imbalance of the Treg/Th17 axis may be the key immunological mechanism of YWS in the treatment of psoriasis through metabolic pathways and influencing key proteins. The results not only expand the therapeutic targets and approaches for the treatment of psoriasis, which is a challenging and complex disease, but also deepens the understanding of the mechanism of YWS in the treatment of psoriasis and other important conditions to open up a new way of thinking for research on YWS in the treatment of psoriasis.

Gomisin M2 alleviates psoriasis­like skin inflammation by inhibiting inflammatory signaling pathways.

Psoriasis, a chronic inflammatory skin disease, is characterized by the excessive proliferation and impaired differentiation of epidermal keratinocytes and is accompanied by the increased infiltration of inflammatory cells. The condition requires long­term treatment and has no definitive cure. Hence, supplements and therapeutic agents have been intensely investigated. Gomisin M2 (GM2), a lignan extracted from Schisandra chinensis (Turcz). Baill. (Schisandraceae; S. chinensis), has demonstrated diverse pharmacological properties, including anticancer, anti­inflammatory and antiallergic effects. Based on these findings, the present study examined the effects of GM2 on an imiquimod (IMQ)­induced psoriasis mouse model and on keratinocytes stimulated by tumor necrosis factor (TNF)­α and interferon­Î³. IMQ was topically applied to the back skin of mice for 7 consecutive days, and the mice were orally administered CD. These results showed that the oral administration of GM2 suppressed the symptoms of psoriasis, as evidenced by reductions in skin thickness, psoriasis area severity index scores for psoriasis lesions, transepidermal water loss and myeloperoxidase (MPO)­associated cell infiltration. Furthermore, GM2 reduced the pathologically increased levels of immunoglobulin G2a, MPO and TNF­α in the serum and T helper (Th)1 and Th17 cell populations in the spleen. GM2 decreased the gene expression of inflammatory­related cytokines and chemokines and inhibited the expression of signal transducer and activator of transcription 1 and nuclear factor­κB in the activated keratinocytes. These results suggested that GM2 from S. chinensis is a potential therapeutic candidate to alleviate psoriasis­like skin inflammation.

Deciphering the mechanism of Fang-Ji-Di-Huang-Decoction in ameliorating psoriasis-like skin inflammation via the inhibition of IL-23/Th17 cell axis.

ETHNOPHARMACOLOGICAL RELEVANCE: In the theory of traditional Chinese medicine (TCM), the etiology of psoriasis is assigned to damp-heat internal depression, blood poisoning, Yin deficiency and loss of nourishment. Fang-Ji-Di-Huang-Decoction (FJDH), a well-known Chinese traditional formula, is recorded in Synopsis of the Golden Chamber (in the Eastern Han Dynasty). This decoction is composed of dried roots of Rehmannia glutinosa (Gaertn.) DC., dried roots of Stephania tetrandra S. Moore, roots of Saposhnikovia divaricata (Turcz.) Schischk., dried twigs of Cinnamomum cassia (L.) J. Presl and dry roots and rhizomes of Glycyrrhiza uralensis Fisch. FJDH has the function of clearing heat, removing dampness, and nourishing blood. Therefore, in modern medical theory, FJDH can regulate the infiltration of inflammatory cells and the secretion of inflammatory cytokines in the process of psoriasis. AIM OF THE STUDY: This study evaluated whether FJDH treated psoriasis and its specific mechanism for the efficacy in mice. At the same time, it clarified s what important role of the copperware played s in the curative effect of FJDH. METHODS AND MATERIALS: We used imiquimod (IMQ) to induce psoriasis-like skin inflammation in mice. Mice were treated with imiquimod for one week, and FJDH was given by intragastric administration one week in advance. Record the weight change and psoriasis Area and Severity Index (PASI) score of the mouse during the whole process to assess the severity of psoriasis were recored mouse. Hematoxylin-eosin staining was used to evaluate skin tissue structure change. Immunohistochemistry was performed to observe the expressions of Ki67 and proliferating cell nuclear antigen (PCNA) in skin tissue. In order to further explore the mechanism of FJDH in the treatment of psoriasis, we used network pharmacology to predict the therapeutic target. TCMSP and Uniprot were used to collect compounds and genes of FJDH. Genecards was used for obtaining genes of psoriasis. String was used to analyze the relationship between genes. Metascape was used for gene enrichment and pathway prediction. Using molecular biological detection methods, we verified whether FJDH could regulate Interleukin 17 signaling pathway and T helper cell 17 (Th17) cell differentiation. Flow cytometry was used to detect Th17 cell differentiation in mouse spleen. Quantitative Real-time PCR was used to detect mRNA expression of IL-17 signaling pathway-related inflammatory factors in mouse skin tissues. UPLC-Triple TOF-MS/MS and Phenol-Sulphate colorimetry were used to explore the main components of FJDH, and further elaborate the mechanism of FJDH in the treatment of psoriasis. RESULTS: FJDH with copper was found to improve psoriasis-related pathological symptoms in a dose-dependent manner, possibly by inhibiting IL-23/Th17 cell axis and reducing inflammatory cytokines such as IL-17A, IL-17F, IL-22 and TNF-α. Furthermore, R. glutinosa polysaccharide in FJDH was the main substance that exerted the drug effect and it work by forming a complex with copper. Experimental data proved that Rehmannia glutinosa polysaccharide and copper complex had the same pharmacological activity and therapeutic effect as FJDH. CONCLUSIONS: FJDH may attenulated imiquimod-induced psoriasis-like skin inflammation in mice by inhibiting IL-23/Th17 cell axis. The material basis for the therapeutic effect may be the formation of complexes between the polysaccharides of R. glutinosa and copper in FJDH to produce the effect. These findings suggest that FJDH can be used as an effective Chinese medicine to treat psoriasis.

Tuhuaiyin alleviates imiquimod-induced psoriasis via inhibiting the properties of IL-17-producing cells and remodels the gut microbiota.

BACKGROUND: psoriasis is a chronic inflammatory skin disease. The accumulation of IL-17 cytokines in the lesions leads to epidermis proliferation. Traditional Chinese medicine has a significant effect on psoriasis treatment. Among them, Tuhuaiyin is a representative prescription, which has an outstanding curative effect in acute and remission stage. METHODS: To reveal the target and molecular mechanism of Tuhuaiyin, systematic pharmacology platform and database screening were used to construct the Tuhuaiyin interaction network with compounds, targets and diseases. The intervention of Tuhuaiyin on keratinocyte proliferation and inflammation was verified in the model of psoriasis-like lesions induced by imiquimod. The effect on the number and function of IL-17-producing cells was detected, and the regulatory effect of Tuhuaiyin on gut microbial was explored. RESULTS: 32 selected active molecules in Tuhuaiyin acted on psoriasis biological processes. Tuhuaiyin significantly alleviates erythema and scales in the psoriasis like mouse model induced by imiquimod. Excessive proliferation of keratinocytes and infiltration of inflammatory cells were restrained in the dermis by using Tuhuaiyin. The expression of IL-17 was down-regulated in skin and peripheral blood. The proportion of IL-17-producing cells was decreased in immune organs. And phosphorylation of JNK inhibited in skin lesions. At the same time, the change of gut microbial diversity in the psoriasis-like model was improved. CONCLUSION: our study predicted and verified the molecular immunological mechanism of Tuhuaiyin, alleviated the abnormal proliferation of keratinocytes by inhibiting the proportion of IL-17-producing cells and the expression of IL-17 cytokines. Taken together, our data identify the therapeutic potential of Tuhuaiyin for psoriasis.

Randialic acid B and tomentosolic acid block formyl peptide receptor 1 in human neutrophils and attenuate psoriasis-like inflammation in vivo.

Psoriasis is a long-lasting inflammatory skin disease lacking proper cure. Dysregulated activation of neutrophils is a major pathogenic factor in psoriasis. Formyl peptide receptor 1 (FPR1) triggers neutrophil activation in response to bacteria- or mitochondria-derived N-formyl peptides, but its significance in neutrophilic psoriasis remains unknown. In this study, we discovered two derivatives of ursolic acid, 3ß-hydroxyurs-12,18-dien-28-oic acid (randialic acid B, RAB) and 3ß-hydroxyurs-12,19-dien-28-oic acid (tomentosolic acid, TA), as FPR1 inhibitors in human neutrophils with ability to suppress psoriatic symptoms in mice. Both RAB and TA, triterpenoids of traditional medicinal plant Ilex kaushue, selectively inhibited reactive oxygen species production, elastase release, and CD11b expression in human neutrophils activated by FPR1, but not non-FPR1 agonists. Importantly, RAB and TA inhibited the binding of N-formyl peptide to FPR1 in human neutrophils, neutrophil-like THP-1 cells, and hFPR1-transfected HEK293 cells, indicating FPR1 antagonism. Moreover, in assays induced by various concentrations of FPR1 agonist, both RAB and TA acted competitively for its binding to the FPR1 receptor. The FPR1-downstream signaling such as Ca2+ mobilisation and activation of Akt and MAPKs was also competitively inhibited. In addition, imiquimod-induced psoriasis-like symptoms, including epidermal hyperplasia, desquamation with scaling, neutrophil skin infiltration, and transepidermal water loss were significantly reduced by both RAB and TA. The results illustrate a possible role of human neutrophils FPR1 receptor in psoriasis-like inflammation. Accordingly, triterpenoids RAB and TA represent novel FPR1 antagonists and exhibit therapeutic potential for treating neutrophilic inflammatory skin diseases.

Anti-Angiogenic Efficacy of PSORI-CM02 and the Associated Mechanism in Psoriasis In Vitro and In Vivo.

Psoriasis is a chronic proliferative autoimmune dermatologic disease characterised by abnormal angiogenesis. Thus, regulating angiogenesis in the skin is an important treatment strategy for psoriasis. PSORI-CM02, an empirical Chinese medicine formula optimised from Yin Xie Ling, was created by the Chinese medicine specialist, Guo-Wei Xuan. Clinical studies have shown that PSORI-CM02 is safe and effective for the treatment of psoriasis. However, its anti-psoriatic mechanisms remain to be further explored. In this study, we investigated the effects of PSORI-CM02 on angiogenesis in the skin and the underlying mechanisms in IL-17A-stimulated human umbilical vein endothelial cells (HUVECs) and a murine model of imiquimod (IMQ)-induced psoriasis. In vitro, PSORI-CM02 significantly inhibited the proliferation and migration of IL-17A-stimulated HUVECs in a dose-dependent manner. Further, it markedly regulated the antioxidative/oxidative status and inflammation; suppressed the expression of VEGF, VEGFR1, VEGFR2, ANG1, and HIF-1α; and reduced the phosphorylation of MAPK signalling pathway components in IL-17A-stimulated HUVECs. In vivo studies showed that PSORI-CM02 markedly reduced angiogenesis in the skin of mice with IMQ-induced psoriasis, while significantly rebalancing antioxidant/oxidant levels; inhibiting the production of IL-6, TNF-α, IL-17A, and IL-17F; and repressing the synthesis of angiogenic mediators. In addition, PSORI-CM02 markedly reduced the activation of the MAPK signalling pathway in psoriatic skin tissue. Taken together, our results demonstrated that PSORI-CM02 inhibited psoriatic angiogenesis by reducing the oxidative status and inflammation, suppressing the expression of angiogenesis-related molecules, and inhibiting the activation of the MAPK signalling pathway in vitro and in vivo.

Discovery of a novel RORγ antagonist with skin-restricted exposure for topical treatment of mild to moderate psoriasis.

Clinical success of IL-17/IL-23 pathway biologics for the treatment of moderate to severe psoriasis suggests that targeting RORγt, a master regulator for the proliferation and function of Th17 cells, could be an effective alternative. However, oral RORγ antagonists (VTP43742, TAK828) with high systemic exposure showed toxicity in phase I/II clinical trials and terminated development. To alleviate the potential safety concerns, identifying compounds with skin-restricted exposure amenable for topical use is of great interest. Systematic structure activity relationship study and multi-parameter optimization led to the discovery of a novel RORγ antagonist (SHR168442) with desired properties for a topical drug. It suppressed the transcription of IL-17 gene, leading to reduction of IL-17 cytokine secretion. It showed high exposure in skin, but low in plasma. Topical application of SHR168442 in Vaseline exhibited excellent efficacy in the imiquimod-induced and IL-23-induced psoriasis-like skin inflammation mouse models and correlated with the reduction of Th17 pathway cytokines, IL-6, TNFα and IL-17A. This work demonstrated restricted skin exposure of RORγ antagonist may provide a new topical treatment option as targeted therapeutics for mild to moderate psoriasis patients and may be suitable for the treatment of any other inflammatory disorders that are accessible locally.

Abietic acid ameliorates psoriasis-like inflammation and modulates gut microbiota in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Abietic acid (AA), an antibacterial terpenoid, was initially isolated from rosin which has been used as a traditional Chinese medicine to treat psoriasis. In our previous works, we found that water-processed rosin (WPR) can alleviate imiquimod (IMQ)-induced psoriasis-like inflammation in mice. However, the efficacy of AA, the main component of WPR, against psoriasis remains unclear. MATERIALS AND METHODS: In this study, we confirmed the anti-psoriasis efficacy of AA (40 mg/kg daily for 7 days) in IMQ-induced psoriasis-like inflammation BALB/c mouse model by the psoriasis area severity index (PASI), flow cytometry, ELISA, histopathological and immunohistochemical analysis. Furthermore, we detected the relative abundance of gut microbe using high-throughput 16S rRNA gene sequencing to validate whether AA modulate gut microbe. RESULT: Oral administration of AA ameliorates IMQ-induced psoriasis-like skin inflammation through reducing PASI scores, regulating the balance of Th17/Treg cells in the mouse spleen, and downregulating the level of serum cytokines such as TNF-α, IL-17A, TGF-1ß, and IL-23. 16S rRNA gene sequencing revealed that the relative abundance of gut bacteria related to inflammation, such as, Anaerotruncus and Christensenella at genus level were decreased, while Kurthia, Citrobacter, and Klebsiella at genus level were increased in AA group mice. Additionally, the correlation analysis illustrated that the key microbiota had a close relationship with the psoriasis-like inflammation related indexes. CONCLUSION: AA might exert the anti-psoriasis effect via inhibiting Th17-related immune responses, hinting that it might be a candidate for treating psoriasis. Meanwhile, the alteration of intestinal microbiota by AA treatment is another possible explanation for the amelioration of imiquimod-induced psoriasis-like inflammation.

Chemical profiling and anti-psoriatic activity of marine sponge (Dysidea avara) in induced imiquimod-psoriasis-skin model.

Since Marine sponge Dysidea avara is regarded as a source of anti-inflammatory compounds, we decided to evaluate its potential anti-psoriatic activity in a psoriasis Imiquimod-induced in the mouse model. Psoriatic mice were treated with three different methanolic extracts of Dysidea avara compared with betamethasone-treated mice in in- vivo studies. Clinical skin severity was assessed with the psoriasis area index (PASI), whilst ELISA detected the expression of TNF-α, IL-17A, and IL-22. Dysidea avara activity was studied by employing GC-MS (to distinguish compounds), HPTLC (for skin permeation and accumulation), and SEA DOCK to predict single compound potential anti-inflammatory activity. After 7 days of treatment, mice treated with Dysidea avara displayed a dose-dependent, statistically significant improvement compared to controls (p< 0.001). In line with the clinical results, ELISA revealed a statistically significant decrease in IL-22, IL-17A, and TNF-α after treatment; the same SEA DOCK analysis suggests a possible anti-psoriatic activity of the extracts.

Role of keratinocytes and immune cells in the anti-inflammatory effects of Tripterygium wilfordii Hook. f. in a murine model of psoriasis.

BACKGROUND: Tripterygium wilfordii Hook. f. (TwHf) belonging to the Celastraceae family is widely used for psoriasis treatment, especially in topical therapy in Chinese traditional medicine. PURPOSE: In this study, we investigated the anti-psoriatic effects of topical administration of Tripterygium wilfordii Hook. f. root decoction (TwHf-RD), as well as its safety and potential mechanisms of action in vivo and in vitro. METHODS: Psoriasis-like lesions were induced in mice using imiquimod (IMQ). The liver and kidney function and the pathological changes in the liver, kidney, and spleen were measured using ELISA and hematoxylin and eosin (H&E) staining after TwHf-RD treatment. H&E staining was used to determine the optimum concentration of TwHf-RD. The expression levels of ki67 and apoptosis related-factors in vivo and in vitro were measured by immunohistochemical staining, flow cytometry, and western blotting. Immunocyte differentiation and pro-inflammatory cytokine (IL-17A, IL-17F, IL-10, IL-22, IL-23, IFN-γ, and TNF-α) expression levels were determined by flow cytometry and RT-qPCR. RESULTS: TwHf-RD treatment attenuated skin inflammation, inhibited keratinocyte (KC) proliferation, increased the levels of apoptosis factors, and influenced the differentiation and inflammatory response of T lymphocytes and regulatory T cells in mice. In vitro experiments proved that Tripterygium wilfordii Hook. f. root extract (TwHf-RE) regulates the proliferation and apoptosis of PAM212 cells. CONCLUSION: TwHf-RD alleviates IMQ-induced psoriasis lesions by regulating the proliferation and apoptosis of KC and immune cells and by inhibiting immunocyte differentiation and pro-inflammatory cytokine expression.

Uncovering the mechanism of Jueyin granules in the treatment of psoriasis using network pharmacology.

ETHNOPHARMACOLOGICAL RELEVANCE: Our clinical practice demonstrated that Jueyin granules (JYG) benefit patients with mild to moderate psoriasis vulgaris without apparent adverse effects. JYG have been shown to inhibit epidermal proliferation in an imiquimod (IMQ)-induced psoriasis-like mouse model, as well as keratinocyte proliferation. Moreover, JYG causes no acute or chronic toxicity in animal models. However, its related molecular mechanism has still not been elucidated. AIM OF THE STUDY: To assess the mechanism of JYG against psoriasis. MATERIALS AND METHODS: This study combined network pharmacology analysis with experiments to investigate the mechanism of JYG against psoriasis. First, the molecular docking technology was used to construct the network of medicinal materials-core active plant ingredients-core targets and identify possible drug targets. Next, high-performance liquid chromatography (HPLC) was used for quality control of JYG. Finally, a mice model of psoriasis was used to further verify the effects of JYG. RESULTS: (1) Molecular docking analysis of network pharmacology revealed that the therapeutic effects of JYG on psoriasis might be achieved through Vitamin D Receptor (VDR) effects. (2) The concentrations of chlorogenic acid and paeoniflorin were determined using HPLC to establish quality control of JYG. (3) JYG ameliorated pathological characteristics that included in vivo reductions in erythema, scale, and infiltration scores of back and ear lesions in IMQ-induced psoriasis-like mice. Moreover, a reduced number of PCNA-positive and Ki67-positive cells were observed in the epidermis of JYG-treated lesions. JYG also reduced inflammation (interleukin (IL)-17, IL-23) in the peripheral blood of IMQ-induced psoriasis-like mice. As expected, JYG was found to upregulate VDR expression and downregulate p-STAT3 expression in the IMQ group, which may contribute to its mechanism against psoriasis. CONCLUSION: Overall, this study clarifies the mechanism of JYG against psoriasis and provides evidence to support its clinical use.

Kan-Lu-Hsiao-Tu-Tan, a traditional Chinese medicine formula, inhibits human neutrophil activation and ameliorates imiquimod-induced psoriasis-like skin inflammation.

ETHNOPHARMACOLOGICAL RELEVANCE: Kan-Lu-Hsiao-Tu-Tan (KLHTT) is a popular traditional Chinese medicine for treating various inflammatory diseases. AIM OF THE STUDY: The aim of the present study was to investigate the anti-inflammatory effects of KLHTT on human neutrophils and its therapeutic potential in treating imiquimod (IMQ)-induced psoriasis-like skin inflammation. MATERIALS AND METHODS: Spectrophotometry, flow cytometry, and microscopy with immunohistochemical staining were used to evaluate superoxide anion generation, elastase release, CD11b expression, adhesion, and neutrophil extracellular trap (NET) formation in activated human neutrophils. Reactive oxygen species (ROS) and reactive nitrogen species in cell-free systems were measured using a multi-well fluorometer or a spectrophotometer. A psoriasis-like skin inflammation was induced in mice using the IMQ cream. RESULTS: KLHTT suppressed superoxide anion generation, ROS production, CD11b expression, and adhesion in activated human neutrophils. In contrast, KLHTT failed to alter elastase release in activated human neutrophils. Additionally, KLHTT had an ROS-scavenging effect in the AAPH assay, but it did not scavenge superoxide anions directly in the xanthine/xanthine oxidase assay. Protein kinase C (PKC)-induced NET formation most commonly occurs through ROS-dependent mechanisms. KLHTT significantly inhibited phorbol 12-myristate 13-acetate, a PKC activator, inducing NET formation. Furthermore, topical KLHTT treatment reduced the area affected by psoriasis area and severity index (PASI) score and ameliorated neutrophil infiltration in IMQ-induced psoriasis-like skin inflammation in mice. CONCLUSIONS: Our data show that KLHTT has anti-neutrophilic inflammatory effects in inhibiting ROS generation and cell adhesion. KLHTT also mitigated NET formation, mainly via an ROS-dependent pathway. In addition, KLHTT reduced neutrophil infiltration and improved the severity of IMQ-induced psoriasis-like skin inflammation in mice. Therefore, KLHTT may prove to be a safe and effective psoriasis therapy in the future.

Tussilagonone Ameliorates Psoriatic Features in Keratinocytes and Imiquimod-Induced Psoriasis-Like Lesions in Mice via NRF2 Activation.

Psoriasis is a common inflammatory skin disorder that is characterized by keratinocyte hyperproliferation and abnormal differentiation, resulting in the thickening of the epidermis and stratum corneum. In this study, we investigated in vitro and in vivo pharmacological effects of tussilagonone (TGN), a sesquiterpenoid isolated from Tussilago farfara, on transcription factors relevant for the pathogenesis of psoriasis. TGN inhibited activation of NF-κB and STAT3, leading to the attenuated expression of psoriasis-related inflammatory genes and suppression of keratinocyte hyperproliferation. Mechanistically, we show that the inhibition of NF-κB and STAT3 by TGN is mediated through activation of the cytoprotective transcription factor NRF2. Evaluation of in vivo antipsoriatic effects of topical TGN in the imiquimod-induced psoriasis-like dermatitis mouse model demonstrated amelioration of imiquimod-induced phenotypical changes, lesion severity score, epidermal thickening, and reduction in dermal cellularity. The spleen index also diminished in TGN-treated mice, suggesting anti-inflammatory properties of TGN. Moreover, TGN significantly attenuated the imiquimod-induced mRNA levels of psoriasis-associated inflammatory cytokines and antimicrobial peptides and reduced epidermal hyperproliferation. Taken together, TGN, as a potent NRF2 activator, is a promising therapeutic candidate for the development of antipsoriatic agents derived from medicinal plants.

Convallatoxin induces HaCaT cell necroptosis and ameliorates skin lesions in psoriasis-like mouse models.

Psoriasis is considered an immune-mediated inflammatory skin disorder that affects the quality of life of nearly four percent of the world population. Considering the side effects of existing therapeutic drugs and the urgent need for new drug development, we screened more than 250 traditional Chinese medicine compounds to identify drugs that significantly reduced the viability of human HaCaT keratinocytes, a psoriasis-related model cell line. Convallatoxin (CNT) was found to be a highly effective inhibitor of HaCaT cell viability. Subsequent mechanistic studies revealed that CNT induced HaCaT cell death by necroptosis rather than by apoptosis. CNT destroyed the membrane integrity of HaCaT cells, as detected by nuclear propidium iodide (PI) staining and lactate dehydrogenase (LDH) release. Additionally, the intercellular levels of adenosine triphosphate (ATP) were lower in HaCaT cells treated with CNT than in control HaCaT cells, and typical necroptosis-associated characteristics were observed by electron microscopy in cells treated with CNT. Furthermore, compared with control HaCaT cells, CNT-treated HaCaT cells produced more reactive oxygen species (ROS), but this effect was inhibited by the antioxidants N-acetyl-cysteine (NAC), diphenyleneiodonium chloride (DPI), and apocynin and the necroptosis inhibitor Nec-1. In addition, antioxidant treatment attenuated necroptotic cell death, suggesting that CNT-induced HaCaT necroptosis is mediated by oxidative stress. More importantly, CNT ameliorated skin lesions and inflammation in imiquimod (IMQ)- and 12-O-tetradecanoyl-phorbol-13-acetate (TPA)-induced psoriasis-like mouse models. In conclusion, our results demonstrate that CNT is cytotoxic against HaCaT cells in vitro and exerts antipsoriatic activities in two mouse models of psoriasis in vivo, making CNT a potential promising candidate drug for future research.

Mechanism of danshensu-induced inhibition of abnormal epidermal proliferation in psoriasis.

Psoriasis is a chronic, inflammatory skin disease with high incidence and high rates of relapse, for which no satisfactory treatments are currently available. Yes-associated protein (YAP) is highly expressed in psoriasis and may regulate the proliferation and apoptosis of keratinocytes. Danshen is a traditional Chinese medicine, commonly used in the treatment of psoriasis. Danshensu is the most abundant water-soluble component of Danshen, but its therapeutic mechanism is still unclear. In this study, MTT was used to detect the effects of different danshensu concentrations (0.125, 0.25, 0.5 mmol/l) on the proliferation of an M5-based psoriasis cell model. The effects of danshensu on cell cycle and apoptosis were detected by flow cytometry. Cyclins and apoptosis-related proteins were evaluated by Western blot. Danshensu (20, 40, 80 mg/kg/day) was administered intraperitoneally to the imiquimod (IMQ) psoriasis mouse model. After 7 days, the expression of YAP in the lesions was detected by immunohistochemistry and Western blot. We found that danshensu reduced the expression of YAP in the M5 psoriasis cell model, inhibited cell proliferation, induced cell cycle arrest in G0/G1 phase, and promoted cell apoptosis. All these effects were partly reverted by YAP overexpression. The skin lesions of IMQ mice were thinned and the scales reduced after intragastric administration of danshensu, which also resulted in dose-dependent inhibition of YAP expression. We concluded that danshensu prevents abnormal epidermis proliferation in psoriasis possibly by modulating YAP expression. Our work can provide a theoretical basis for the clinical application of Danshen in the treatment of psoriasis.

ERK inhibitor JSI287 alleviates imiquimod-induced mice skin lesions by ERK/IL-17 signaling pathway.

Many studies confirmed that the over-activation of RAF-MEK-ERK signaling pathway plays a central role in human cancers. To avoid drug resistance during cancer treatment, many researchers focused on the study of the downstream therapeutic target of RAF-MEK-ERK signaling pathway. Therefore, ERK1/2 became a hot anticancer target. It has been shown that ERK phosphorylation could activate Th17 cells and therefore induce inflammatory diseases. Due to these results, inhibition of ERK, as a potential drug target, could provide a solution for autoimmune diseases, especially T cell mediated diseases. In this study, a small synthetic molecule JSI287 was found with the function of alleviating IMQ-induced mice skin lesions through ERK/IL-17 signaling pathway during the screening of small molecule databases targeting ERK. The results showed that JS1287 small molecule alleviated epidermal thickness, epidermis congestion, edema and inflammatory cell infiltration, decreased release of inflammatory cytokines of IL-6, IL-12 and IL-17A, and further regulated the mRNA expression of ATF1 and protein expression of ERK1/2 in IMQ-induced skin lesions. Our study suggested that ERK inhibitor JSI287 could be a promising candidate for psoriasis treatment.

PSORI-CM02 alleviates IMQ-induced mouse dermatitis via differentially regulating pro- and anti-inflammatory cytokines targeting of Th2 specific transcript factor GATA3.

The IL-17-producing CD4+ T cell and γδT cells play critical roles in the pathogenesis of psoriasis (PS). PSORI-CM02 is a representative herbal formula for the treatment for PS in South China. It was confirmed to improve PS without obvious side effects in the clinic. Here we sought to clarify whether and how PSORI-CM02 regulates T cell differentiation and functions in IMQ-induced psoriasis-like BALB/c mouse model. Mice pre-treated 3 days with PSORI-CM02 significantly alleviated skin inflammation, as reduced in PASI score and classic psoriatic characteristics in pathological sections. CD3 and CD4 positive T cells were also fewer in the skin lesions of PSORI-CM02 groups, comparing to control group. PSORI-CM02 also decreased pro-inflammatory IFNγ mRNA and IL-17 A mRNA, while increased IL-4 mRNA in mouse skin lesions. In skin draining lymph nodes (DLN), PSORI-CM02 reduced the ratio of γδT cells and inhibited their function of producing IL-17 A. Nevertheless PSORI-CM02 had no effects on the ratio of total TCRß+T cells and CD4 + T cells. But it regulated CD4 + T helper cells differentiation, and resulted in the decreasing percentage of IFNγ producing Th1 cells and IL-17 A producing Th17 cells, while increasing the ratio of IL-4 producing Th2 cells in DLN. Further data showed that PSORI-CM02 promote expression of Th2 specific transcript factor GATA3, but had no effects on T-bet and RORγ. Thus, we tentatively interpret that PSORI-CM02 impairs IMQ-induced psoriasis by promoting Th2 cell response targeting of GATA3.