PSORI-CM02 Formula Increases CD4+ Foxp3+ Regulatory T Cell Frequency and Ameliorates Imiquimod-Induced Psoriasis in Mice

New insight in treating autoimmune diseases by targeting autophagy

Autophagy is a highly conserved biological process in eukaryotes, which degrades cellular misfolded proteins, damaged organelles and invasive pathogens in the lysosome-dependent manner. Autoimmune diseases caused by genetic elements, environments and aberrant immune responses severely impact patients' living quality and even threaten life. Recently, numerous studies have reported autophagy can regulate immune responses, and play an important role in autoimmune diseases. In this review, we summarised the features of autophagy and autophagy-related genes, enumerated some autophagy-related genes involved in autoimmune diseases, and further overviewed how to treat autoimmune diseases through targeting autophagy. Finally, we outlooked the prospect of relieving and curing autoimmune diseases by targeting autophagy pathway.

Yinxieling decoction ameliorates psoriasis by regulating the differentiation and functions of Langerhans cells via the TGF-β1/PU.1/IL-23 signal axis

Langerhans cells (LCs) play a critical role in skin immune responses and the development of psoriasis. Yinxieling (YXL) is a representative Chinese herbal medicine for the treatment of psoriasis in South China. It was found to improve psoriasis without obvious side effects in the clinic. Here we attempted to clarify whether and how YXL regulates the differentiation and functions of LCs in Imiquimod (IMQ)-induced psoriasis in vivo and induced LCs in vitro. The Psoriasis Area Severity Index (PASI) score was used to evaluate the efficacy of YXL for IMQ-induced psoriasis-like mice. Flow cytometry was utilized to analyze the effects of YXL, to regulate the differentiation, migration, maturation, and antigen presentation of LCs. The results show that YXL significantly alleviated skin inflammation, as reduced in PASI score and classic psoriasis characteristics in pathological sections. Although there was no effect on the proportion of total DCs in the skin-draining lymph nodes, the expression of epidermal LCs and its transcription factor PU.1 were both markedly inhibited. LCs were also prevented from migrating from epidermal to skin-draining lymph nodes and mature. In addition, the number of LCs carrying antigens in the epidermis increased, which suggested that YXL could effectively prevent LCs from presenting antigens. In vitro, YXL had a significant impact on inhibiting the differentiation of LCs. Further data showed that YXL decreased the relative expression of transforming growth factor-β (TGFβ) messenger RNA (mRNA) and interleukin-23 (IL-23) mRNAs. Thus, YXL alleviates psoriasis by regulating differentiation, migration, maturation, and antigen presentation via the TGFβ/PU.1/IL-23 signal axis.

Extracts from Seseli mairei Wolff attenuate imiquimod-induced psoriasis-like inflammation by inhibiting Th17 cells

Objective

Seseli mairei Wolff extracts (SMWE) are widely used to treat psoriasis as a Chinese medicine, but their effect and mechanism are unclear. This study verified the effect of SMWE on psoriasis by regulating Th17 cells.

Methods

HaCaT cells were treated with IL-17A in vitro to evaluate the effect of SMWE on psoriasis. In vivo, the mice psoriasis model was established using imiquimod (IMQ, 62.5 mg/d), and intragastrically treated with the different drugs for six days. The severity of skin inflammation was evaluated with Psoriasis Area and Severity Index (PASI) scores and pathology. The levels of inflammation cytokines were assessed with immunofluorescence, immunochemistry, ELISA, and real-time PCR. The number of Th17 cells was determined with flows.

Results

SMWE inhibited the proliferation of HaCaT cells and reduced the IL-17A-induced IL-6 production in vitro. In vivo, SMWE deduced the levels of IL-1β, IL-6, IL-8, IL-17A, IL-17F, IL-22, IL-23, and TNF-α, while increasing the level of IL-10 compared to the model group. SMWE also inhibited the levels of NF-κB, JAK2, and STAT3 proteins, while declining the expressions of Gr-1, and MPO. Interestingly, SMWE significantly decreased the number of Th17 cells.

Conclusion

SMWE inhibited the proliferation of HaCaT cells and attenuated the development of psoriasis lesions by inhibiting Th17 cells to regulate the levels of inflammation cytokines.

Transcriptional regulation on effector T cells in the pathogenesis of psoriasis

Psoriasis is one of the most common inflammatory diseases, characterized by scaly erythematous plaques on the skin. The accumulated evidence on immunopathology of psoriasis suggests that inflammatory reaction is primarily mediated by T helper (Th) cells. The differentiation of Th cells plays important roles in psoriatic progression and it is regulated by transcription factors such as T-bet, GATA3, RORγt, and FOXP3, which can convert naïve CD4+ T cells, respectively, into Th1, Th2, Th17 and Treg subsets. Through the activation of the JAK/STAT and Notch signaling pathways, together with their downstream effector molecules including TNF-α, IFN-γ, IL-17, TGF-β, these subsets of Th cells are then deeply involved in the pathogenesis of psoriasis. As a result, keratinocytes are abnormally proliferated and abundant inflammatory immune cells are infiltrated in psoriatic lesions. We hypothesize that modulation of the expression of transcription factors for each Th subset could be a new therapeutic target for psoriasis. In this review, we will focus on the recent literature concerning the transcriptional regulation of Th cells in psoriasis.

Specific Activation of CB2R Ameliorates Psoriasis-Like Skin Lesions by Inhibiting Inflammation and Oxidative Stress

Psoriasis is a chronic inflammatory skin disease. Inflammation and oxidative stress play crucial roles in the pathogenesis of psoriasis. Cannabinoid receptor type 2 (CB2R) is an attractive target for treating various inflammatory disorders. However, the precise role and mechanism of CB2R activation in psoriasis remain to be further elucidated. In this study, imiquimod (IMQ)-induced experimental psoriasis mice and tumor necrosis factor-α (TNF-α)-activated keratinocytes (HaCaT) were used to examine the effect of CB2R activation on psoriasis-like lesions and the mechanism in vivo and in vitro. Our results demonstrated that activation of CB2R by the specific agonist GW842166X (GW) significantly ameliorated IMQ-induced psoriasiform skin lesions in mice by reducing epidermal thickness and decreasing plaque thickness. On the one hand, GW alleviated inflammation by decreasing inflammatory cytokines and abating inflammatory cell infiltration. On the other hand, this treatment reduced the level of iNOS and downregulated the expression of CB2R in psoriatic skin tissue. Further studies suggested that the Kelch-like ECH-associated protein 1/nuclear factor erythroid-2-related factor (Keap1/Nrf2) signaling pathway might be involved. Our findings reveal that selective activation of CB2R may serve as a new strategy for the treatment of psoriasis.

Deciphering the mechanism of PSORI-CM02 in suppressing keratinocyte proliferation through the mTOR/HK2/glycolysis axis

Hyperplasia of epidermal keratinocytes that depend on glycolysis is a new hallmark of psoriasis pathogenesis. Our previous studies demonstrated that PSORI-CM02 could halt the pathological progression of psoriasis by targeting inflammatory response and angiogenesis, but its effect(s) and mechanism(s) on proliferating keratinocytes remained unclear. In this study, we aim to identify components of PSORI-CM02 that are absorbed into the blood and to determine the effect(s) of PSORI-CM02 on keratinocyte proliferation and its molecular mechanism(s). We used the immortalized human epidermal keratinocyte cell line, HaCaT, as an in vitro model of proliferating keratinocytes and the imiquimod-induced psoriasis mouse (IMQ) as an in vivo model. Metabolite profiles of vehicle pharmaceutic serum (VPS), PSORI-CM02 pharmaceutic serum (PPS), and water extraction (PWE) were compared, and 23 components of PSORI-CM02 were identified that were absorbed into the blood of mice. Both PPS and PWE inhibited the proliferation of HaCaT cells and consequently reduced the expression of the proliferation marker ki67. Additionally, PPS and PWE reduced phosphorylation levels of mTOR pathway kinases. Seahorse experiments demonstrated that PPS significantly inhibited glycolysis, glycolytic capacity, and mitochondrial respiration, thus reducing ATP production in HaCaT cells. Upon treatments of PPS or PWE, hexokinase 2 (HK2) expression was significantly decreased, as observed from the set of glycolytic genes we screened. Finally, in the IMQ model, we observed that treatment with PSORI-CM02 or BPTES, an inhibitor of mTOR signaling, reduced hyperproliferation of epidermal keratinocytes, inhibited the expression of p-S6 and reduced the number of proliferating cell nuclear antigen (PCNA)-positive cells in lesioned skin. Taken together, we demonstrate that PSORI-CM02 has an anti-proliferative effect on psoriatic keratinocytes, at least in part, by inhibiting the mTOR/HK2/glycolysis axis.

The Dopamine Gene Receptors (DRD1-5) Expression Alteration in Psoriasis Patients

BACKGROUND

Psoriasis is a chronic inflammatory autoimmune disease that is considered linked to genetic and environmental factors such as stress. Since the neurotransmitter dopamine has a close association with stress configuration, it can be a candidate for relieving psoriasis representation. In addition to the CNS, immune cells can play a decisive role in regulating immune functions through dopamine synthesis and the expression of its receptors. Altered response of immune cells to dopamine as well as a distorted expression of dopamine receptors (DRs) in immune cells have been reported in some chronic inflammatory conditions.

OBJECTIVE

This study aims the evaluation of dopamine receptor (DR1-DR5) gene expression in mononuclear blood cells of psoriatic patients in comparison with normal individuals.

METHODS

We isolated peripheral mononuclear cells (PBMCs) from blood samples followed by total RNA extraction, cDNA synthesis, and real-time PCR using specific primer pairs.

RESULTS

We found that all types of DRs are expressed in the PBMCs of normal and psoriatic individuals. We also concluded that compared to controls, DR2 and DR4 were overexpressed in psoriasis patients while DR3 was low-expressed.

CONCLUSION

Increased expression of DR2 and DR4 along with decreased expression of DR3 in PBMCs of psoriasis patients not only provide new insight into the pathogenesis of psoriasis but may also be effective in designing future therapeutic strategies attributable to psoriasis.

Potential effects and mechanisms of Chinese herbal medicine in the treatment of psoriasis

ETHNOPHARMACOLOGICAL RELEVANCE

Psoriasis is a chronic inflammatory dermatosis related to high morbidity and mortality. The incidence of psoriasis is increasing in recent decades. Some patients with psoriasis are anxious about the underlying side effects of synthetic drugs they are on. Therefore, they are eager to seek alternative and efficient therapy, such as Chinese herbal medicine (CHM). Researchers have found some CHM provides best source for the development of anti-psoriatic drugs because of their structural diversity and fewer adverse reactions. Some of CHM formulas or active constituents extracted from CHM have been rapidly developed into clinical drugs with good efficacy. At present, along with the CHM formulas, single CHM and its active components have been extensively accepted and utilized in the treatment of psoriasis, whose therapeutic mechanisms hitherto have not been thoroughly illustrated.

AIM OF THE STUDY

This review aimed to comprehensively summarize about the existing therapeutic mechanisms of CHM in the treatment of psoriasis and to provide a reference to develop future related studies in this field.

MATERIALS AND METHODS

Relevant literatures about how CHM treated psoriasis were acquired from published scientific studies (including PubMed, CNKI, Web of Science, Baidu Scholar, The Plant List, Elsevier and SciFinder). All plants appearing in the review have been included in The Plant List or Medicinal Plant Names Services (MPNS).

RESULTS

In this review, we collect numerous literatures about how CHM treats psoriasis via immune cells, signaling pathways and disease-related mediators and systematically elucidates potential mechanisms from the point of the suppression of oxidative stress, the inhibition of abnormal abnormal proliferation and differentiation, the inhibition of immune responses, and the suppression of angiogenesis.

CONCLUSIONS

Psoriasis is considered as a complicated disease caused by interaction among various mechanisms. The CHM formulas, single CHM and its active components have considerable positive reports about the treatment of psoriasis, which brings hope for a promising future of CHM in the clinical therapy of psoriasis. In the paper, we have concluded that the existing therapeutic mechanisms of CHM in the treatment of psoriasis.

Topical Application of Tetrandrine Nanoemulsion Promotes the Expansion of CD4+Foxp3+ Regulatory T Cells and Alleviates Imiquimod-Induced Psoriasis in Mice

There is compelling evidence that CD4⁺Foxp3⁺ regulatory T cells (Tregs) are indispensable in the inhibition of autoimmune inflammatory responses, including psoriasis. Recently, we showed that systemically treatment with tetrandrine (TET), a two-pore channel inhibitor identified from the Chinese herb Stephania tetrandra S. Moor, could promote the proliferative expansion of Tregs in mice through stimulation of TNF-TNFR2 interaction. We thus hypothesized that topical administration of TET might also expand Tregs and consequently inhibit psoriasis. To this end, we developed a TET nanoemulsion and examined its effect on the expansion of Tregs after topical administration on mouse psoriasis induced by imiquimod. The result of our experiment showed that topical treatment with TET nanoemulsion markedly increased the proportion and number of Tregs in the spleen, as well as TNFR2 and Ki-67 expression by Tregs, in WT and TNFR1 KO mice, but not in TNFR2 KO mice. Consequently, TET nanoemulsion potently inhibited IL-17-expressing cells in the spleen and lymph nodes of imiquimod-treated WT mice, accompanied by decreased serum levels of IL-17A, INF-γ, and TNF and their mRNA levels in the flamed lesion. Importantly, TET nanoemulsion treatment markedly inhibited the development of psoriasis-like disease in WT and TNFR1 KO mice but not in TNFR2 KO mice. Therefore, our study indicates that the topical administration of TET could also stimulate the expansion of Tregs through the TNF-TNFR2 pathway. This effect of TET and its analogs may be useful in the treatment of inflammatory skin diseases such as psoriasis.

Differential role of TNFR1 and TNFR2 in the development of imiquimod-induced mouse psoriasis

Tumor necrosis factor alpha (TNF) has been implicated in the pathogenesis of psoriasis and anti-TNF therapeutics are used in the treatment of psoriasis in the clinic. However, considerable proportion of patients fail to respond to anti-TNF treatment. Furthermore, anti-TNF therapy induces de novo development of psoriasis in some patients with other type of autoimmune disorders. Therefore, further understanding of the role of TNF-TNFR signaling in pathogenesis of psoriasis remains a critical to devise safer and more effective treatment. In this study, it is shown that in imiquimod-induced mouse psoriasis model, TNF receptor type 1 (TNFR1) deficiency inhibited the development of skin diseases. In sharp contrast, TNF receptor type 2 (TNFR2) deficiency led to more severe psoriasis that was associated with increased Th1 and Th17 responses and reduced number of CD4⁺ Foxp3⁺ regulatory T cells (Tregs). Importantly, adoptive transfer of WT Tregs was able to attenuate inflammatory responses in imiquimod-treated TNFR2^-/- mice, suggestive of a role of malfunctioned Tregs in mice deficient in TNFR2. RNA sequencing data revealed that Tregs deficient in TNFR2 exhibited down-regulation of different biological processes linked to proliferative expansion. Taken together, our study clearly indicated that TNFR1 was pathogenic in mouse psoriasis. In contrast, through boosting the proliferative expansion of Tregs, TNFR2 was protective in this model. The data thus suggest that TNFR1-specific antagonist or TNFR2-specific agonist may be useful in the treatment of patients with psoriasis.

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.

Chinese Medicine Formula PSORI-CM02 Alleviates Psoriatic Dermatitis via M-MDSCs and Th17 Crosstalk

Psoriasis is a chronic inflammatory skin disease that is associated with multiple coexisting conditions. Extensive literature suggests that psoriasis is a T-cell-mediated condition, and its pathogenesis is related to dysfunction of the immune system. Myeloid-derived suppressor cells (MDSCs) are a group of heterogeneous myeloid cells that have suppressive effects on T cells. MDSCs are present at very low levels in healthy individuals but can substantially expand in tumours or inflammatory conditions. PSORI-CM02, a Chinese medical formula designed based on the Chinese medicine theory (Blood Stasis), has been prescribed extensively for psoriasis therapy and shows a stable clinical effect and safety. This study discusses the mechanisms of MDSCs involved in disease development and therapeutic progress. Our data provides evidence that monocytic myeloid-derived suppressor cells (M-MDSCs) play a role in IMQ-induced psoriatic dermatitis. Functional characterization and correlation analysis indicated that MDSCs are positively correlated with Th17 cells. PSORI-CM02 alleviated IMQ-induced psoriatic dermatitis and suppressed the proliferation of Th17 cells via M-MDSC-induced Arg1 upregulation, suggesting M-MDSCs could be a novel therapeutic target for psoriasis, and PSORI-CM02 exerted its effects via the perturbation of M-MDSCs and Th17 cell crosstalk.

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

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

Importance of Redox Equilibrium in the Pathogenesis of Psoriasis-Impact of Antioxidant-Rich Diet

Psoriasis is a common, chronic, hyperproliferative, inflammatory skin disease occurring in most ethnic groups in the world. The disease is hereditary but the process of its inheritance is complex and still not fully understood. At the same time, it has been observed that psoriatic lesions may be triggered by certain prooxidative external factors: using narcotics, smoking, drinking alcohol, physical and mental stress, as well as bacterial infections and injury. Since the main physiological marker of psoriasis relates to disorders in the organism's antioxidative system, it is necessary to develop a well-balanced combination of pharmaceuticals and dietary antioxidants to facilitate the effective treatment and/or prevention of the disease. The dietary sources of antioxidants must be adequate for chronic use regardless of the patient's age and be easily available, e.g., as ingredients of regular food or dietary supplements. Diet manipulation is a promising therapeutic approach in the context of modulating the incidence of chronic diseases. Another potentially viable method entails the use of nutrigenomics, which guarantees a multiaspectual approach to the problem, including, in particular, analyses of the genetic profiles of psoriasis patients with the view to more accurately targeting key problems. The present paper pertains to the significance of redox equilibrium in the context of psoriasis. Based on information published in worldwide literature over the last decade, the impact of dietary exogenous antioxidants on the course of this chronic disease was analysed.

Study on Anti-Inflammatory Effect and Major Anti-Inflammatory Components of PSORI-CM02 by Zebrafish Model

PSORI-CM02 is an optimization formula of PSORI-CM01, which is a clinical herbal formula for the treatment for psoriasis in the Guangdong Provincial Hospital of Chinese Medicine. Previous research indicates that it plays a critical role in anti-inflammation and immunoregulation. Rhizoma smilacis glabrae (RSG) is one herbal medicine of PSORI-CM02, whose effective anti-inflammatory component is astilbin. This study aims to test the anti-inflammatory and immunoregulation effects of astilbin as well as RSG in PSORI-CM02, and we, respectively, used the CuSO₄-induced neutrophil-specific transgenic zebrafish model Tg(mpx: EGFP) and the melanin allele mutated Albino strain zebrafish model to visualize the effects of neutrophil recruitment and macrophage phagocytosis. Our data indicated that both PSORI-CM02 and astilbin had anti-inflammatory effects, leading to a reduction in the recruitment of neutrophils and promotion in macrophage phagocytosis. Nevertheless, the negative liquor of Rhizoma smilacis glabrae (PSORI-CM02 without RSG) also had anti-inflammatory and promoting macrophage phagocytosis effects. The results revealed the formula excluding RSG also had anti-inflammatory and immunoregulation effects, which demonstrated that RSG was not the major anti-inflammatory herbal medicine in PSORI-CM02. Similarly, astilbin was not the major anti-inflammatory active ingredient in the formula. The anti-inflammatory and the promotion of macrophage phagocytosis effect of PSORI-CM02 in vivo zebrafish were the results of multiple component interaction, which was the common characteristic of the Chinese medicine compound.

Instantaneous depolarization of T cells via dopamine receptors, and inhibition of activated T cells of Psoriasis patients and inflamed human skin, by D1-like receptor agonist: Fenoldopam

Activated T cells are pathological in various autoimmune and inflammatory diseases including Psoriasis, and also in graft rejection and graft-versus-host-disease. In these pathological conditions, selective silencing of activated T cells through physiological receptors they express remains a clinical challenge. In our previous studies we found that activation of dopamine receptors (DRs) in resting human T cells activates these cells, and induces by itself many beneficial T cell functions. In this study, we found that normal human T cells express all types of DRs, and that expression of D1R, D4R and D5R increases profoundly after T cell receptor (TCR) activation. Interestingly, DR agonists shift the membrane potential (V_m ) of both resting and activated human T cells, and induces instantaneous T cell depolarization within 15 seconds only. Thus, activation of DRs in T cells depolarize these immune cells, alike activation of DRs in neural cells. The skin of Psoriasis patients contains 20-fold more D1R⁺ T cells than healthy human skin. In line with that, 25-fold more D1R⁺ T cells are present in Psoriasis humanized mouse model. Highly selective D1-like receptor agonists, primarily Fenoldopam (Corlopam) - a D1-like receptor agonist and a drug used in hypertension, induced the following suppressive effects on activated T cells of Psoriasis patients: reduced chemotactic migration towards the chemokine SDF-1/CXCL12; reduced dramatically the secretion of eight cytokines: tumor necrosis factor-α, interferon-γ, interleukin-1β (IL-1β), IL-2, IL-4, IL-6, IL-8 and IL-10; and reduced three T cell activation proteins/markers: CD69, CD28 and IL-2. Next, we invented a novel topical/dermal Fenoldopam formulation, allowing it to be spread on, and providing prolonged and regulated release in, diseased skin. Our novel topical/dermal Fenoldopam: reduced secretion of the eight cytokines by activated human T cells; reduced IL-1β and IL-6 secretion by human lipopolysaccharide-inflamed skin; eliminated preferentially >90% of live and large/proliferating human T cells. Together, our findings show for the first time that both resting and activated T cells are depolarized instantaneously via DRs, and that targeting D1-like receptors in activated T cells and inflamed human skin by Fenoldopam, in Psoriasis, and potentially in other T cell-mediated diseases, could be therapeutic. Validation in vivo is required.

PSORI-CM02 formula alleviates imiquimod-induced psoriasis via affecting macrophage infiltration and polarization

AIMS

Psoriasis is a refractory skin disease characterized by macrophage cell infiltrated in the dermal layer. Macrophages can simultaneously polarize into two distinct functional subtypes, M1 and M2, and this process is affected by the microenvironment, cytokines and JAK/STAT pathways. Formula PSORI-CM02 is a novel Chinese medicine used to alleviate psoriasis symptoms and regulate T cell differentiation and epithelial cell proliferation. However, the effects of PSORI-CM02 in imiquimod (IMQ)-induced psoriasis and macrophage infiltration and polarization in the dermis remain unknown.

MAIN METHODS

Imiquimod induced psoriasis mice model and M1/M2 polarization model on mice peritoneal macrophages cell line RAW264.7 in vitro were used to observe the therapeutic effect of PSORI-CM02 on skin and its molecular mechanisms.

KEY FINDINGS

PSORI-CM02 can significantly improve skin lesions and reduce macrophage infiltration in mice induced by imiquimod. After treatment with PSORI-CM02 formula, M1 macrophage mediators were significantly reduced, while M2 mediators were significantly increased in mice. Similarly in vitro, M1 macrophage proliferation was suppressed and M2 macrophage proliferation was elevated by PSORI-CM02 in the presence of LPS and IL-4, respectively. The elevated expression of TNF-α, iNOS, and IL-1β induced by LPS was reduced, while the expression of Arg-1, Fizz-1, Ym-1, and IL-10 induced by IL-4 was elevated in PSORI-CM02-treated cells. Finally, we found that the effects of PSORI-CM02 in macrophage polarization were associated with regulation of STAT1 and STAT6 expression, which were activated by LPS and IL-4, respectively.

SIGNIFICANCE

Our novel findings reveal that PSORI-CM02 may possess therapeutic action in psoriasis treatment by regulating the infiltration and polarization of macrophages in the dermal layer.

PSORI-CM02 ameliorates psoriasis in vivo and in vitro by inducing autophagy via inhibition of the PI3K/Akt/mTOR pathway

BACKGROUND

Psoriasis is an inflammatory skin disease that affects an estimated 3% of the world's population. PSORI-CM02 is an empirically developed Chinese medicine formula optimised from Yin Xie Ling, summarised by national medical master Guo-Wei Xuan, that has been used for decades to treat psoriasis in the Guangdong Provincial Hospital of Chinese Medicine. However, its anti-psoriatic mechanisms are still poorly understood. In this study, we explored the effects of PSORI-CM02 on autophagy and the underlying mechanisms in TNF-α-stimulated HaCaT cells and in a mouse model of imiquimod-induced psoriasis.

METHODS

Cell viability was assessed by MTT assay. Apoptosis was detected by annexin V-FITC/PI double-staining and caspase-3 assays. Autophagy was detected by electron microscopy, RT-PCR and western blotting. The PI3K/Akt/mTOR pathway was analysed by western blotting and immunochemical analysis.

RESULTS

PSORI-CM02 induced autophagy and thus inhibited the proliferation of HaCaT cells via suppression of the PI3K/Akt/mTOR pathway. In mice with IMQ-induced psoriasis, PSORI-CM02 relieved psoriasis symptoms, induced autophagy and inhibited the phosphorylation of the PI3K/AKT/mTOR pathway in the skin.

CONCLUSION

These results suggest that PSORI-CM02 treats psoriasis by inducing autophagy via inhibition of the PI3K/Akt/mTOR pathway.

Betulinic acid suppresses Th17 response and ameliorates psoriasis-like murine skin inflammation

Psoriasis is a common inflammatory skin disease. Current treatment for psoriasis relies on conventional immunosuppressive agents. However, long-term treatment with global immunosuppression may cause various side effects. Thus, it is compelling to seek alternative drugs for treating psoriasis with potentially less side effects. Betulinic acid (BA) is a naturally occurring pentacyclic triterpene, an ingredient that originally exists in natural plants and lacks systemic toxicity. BA can regulate immunity with anti-fibrotic, anti-inflammatory and antioxidant properties. However, it's unknown whether BA has a therapeutic effect on psoriasis. The objectives of this study were to investigate whether BA attenuates psoriatic skin inflammation and to identify its mechanisms of action. A murine model of imiquimod-induced psoriasis was utilized to evaluate skin lesion while flow cytometry, immunohistochemistry, quantitative RT-PCR and Western blotting analyses were performed for immunoassays. We found that BA treatment alleviated psoriatic symptoms and inflammatory skin lesion. BA lowered the PASI scores, decreased epidermal thickness and reduced T cell infiltration in the skin lesion. Moreover, BA reduced the frequency of IL-17A-expressing CD4⁺ and γδ T cells in psoriatic mice, but did not alter CD4⁺FoxP3⁺ Treg frequency. BA also reduced IL-17A production but increased anti-inflammatory cytokine IL-10 level in serum of the psoriatic mice. Furthermore, BA inhibited gene expression of pro-inflammatory mediators in skin lesions, including RORγt, IL-17A, IL-6 and TNFα. Importantly, it suppressed NFκB signaling in the skin lesion. Finally, BA inhibited T cell proliferation and IL-17A production by CD4⁺ T-Cells in vitro. Thus, BA attenuates psoriasis and inhibits Th17 development.

miR‑125b‑mediated regulation of cell proliferation through the Jagged‑1/Notch signaling pathway by inhibiting BRD4 expression in psoriasis

Psoriasis is a chronic inflammatory disease characterized by the abnormal differentiation and hyperproliferation of epidermal keratinocytes. The aim of the present study was to investigate the mechanism by which microRNA‑125b (miR‑125b) inhibits the activation of the bromodomain‑containing protein 4 (BRD4)/Notch signaling pathway in psoriasis. The contents of associated miRNAs in serum samples from 32 patients with psoriasis were detected by reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR). The most significantly downregulated miRNA, miR‑125b, was screened out. In experiments using HaCaT cells, the association between miR‑125b and cell proliferation was observed using a Cell Counting Kit‑8 assay, that between miR‑125b and the Notch signaling pathway was observed by western blotting and RT‑qPCR, and that between miR‑125b and the upstream molecule BRD4 of the Notch signaling pathway was observed by luciferase reporter assay and western blotting. The proliferation of HaCaT cells became apparent following miR‑125b inhibition. The Jagged‑1 ligand in the Notch signaling pathway was upregulated, the active intracellular domain of the Notch1 receptor was increasingly truncated, and the Notch signaling pathway was activated. Furthermore, the inhibited miR‑125b contributed directly toward the upstream protein BRD4 3'‑UTR of Jagged‑1, ultimately activating the Notch signaling pathway with the upregulation of Jagged‑1. In conclusion, the proliferation of HaCaT cells mediated by the Jagged‑1/Notch signaling pathway was decreased with the miR‑125b‑mediated inhibition of BRD4 expression. Therefore, miR‑125b may be a biomarker and potential therapeutic target for psoriasis treatment.

In-depth serum proteomics reveals biomarkers of psoriasis severity and response to traditional Chinese medicine

Serum and plasma contain abundant biological information that reflect the body's physiological and pathological conditions and are therefore a valuable sample type for disease biomarkers. However, comprehensive profiling of the serological proteome is challenging due to the wide range of protein concentrations in serum. Methods: To address this challenge, we developed a novel in-depth serum proteomics platform capable of analyzing the serum proteome across ~10 orders or magnitude by combining data obtained from Data Independent Acquisition Mass Spectrometry (DIA-MS) and customizable antibody microarrays. Results: Using psoriasis as a proof-of-concept disease model, we screened 50 serum proteomes from healthy controls and psoriasis patients before and after treatment with traditional Chinese medicine (YinXieLing) on our in-depth serum proteomics platform. We identified 106 differentially-expressed proteins in psoriasis patients involved in psoriasis-relevant biological processes, such as blood coagulation, inflammation, apoptosis and angiogenesis signaling pathways. In addition, unbiased clustering and principle component analysis revealed 58 proteins discriminating healthy volunteers from psoriasis patients and 12 proteins distinguishing responders from non-responders to YinXieLing. To further demonstrate the clinical utility of our platform, we performed correlation analyses between serum proteomes and psoriasis activity and found a positive association between the psoriasis area and severity index (PASI) score with three serum proteins (PI3, CCL22, IL-12B). Conclusion: Taken together, these results demonstrate the clinical utility of our in-depth serum proteomics platform to identify specific diagnostic and predictive biomarkers of psoriasis and other immune-mediated diseases.

Inhibition of spleen tyrosine kinase attenuates psoriasis-like inflammation in mice through blockade of dendritic cell-Th17 inflammation axis

Psoriasis is a debilitating autoimmune disease of the skin characterized by acanthosis and hyperkeratosis resulting from excessive growth of keratinocytes in the epidermis and inflammatory infiltrates in the dermis. Innate immune cells such as dendritic cells (DCs), perform a critical role in the pathophysiology of psoriasis by presenting inflammatory/costimulatory signals for differentiation of Th17 cells. Recent studies point to the involvement of spleen tyrosine kinase (SYK) in inflammatory signaling cascade of DCs. However, it is yet to be determined whether SYK inhibition in DCs would lead to diminishment of psoriatic inflammation. Therefore, our study evaluated the effects of SYK inhibitor, R406 on imiquimod (IMQ)-induced psoriasis-like inflammation, expression of costimulatory/inflammatory molecules in DCs and their relationship with Th17/Treg cells. Our data show that R406 causes attenuation of IMQ-induced dermal inflammation as shown by reduction in ear/back skin thickness, acanthosis and myeloperoxidase activity. This was concurrent with reduction in inflammatory cytokines and co-stimulatory molecules in CD11c + DCs such as IL-6, IL-23, MHCII, and CD40. This favoured the suppression of Th17 cells and upregulation of Treg cells in R406-treated mice with psoriasis-like inflammation. Direct activation of TLR7 by IMQ in splenocytic cultures led to increased SYK expression in CD11c + DCs and release of IL-23/IL-6. IMQ-induced IL-6/IL-23 levels were significantly diminished by SYK inhibitor, R406 in splenocytic cultures. In essence, our study shows that SYK inhibition supresses psoriasis-like inflammation by modifying DC function in mice. Further, it implies that SYK inhibition could be a prospective therapeutic approach for the treatment of psoriasis-like inflammation.

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

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