Liquiritin targeting Th17 cells differentiation and abnormal proliferation of keratinocytes alleviates psoriasis via NF-κB and AP-1 pathway

Single-cell RNA sequencing indicates AP-1 as a potential therapeutic target for autoimmune uveitis

Autoimmune uveitis (AU) is a sight-threatening eye disease, marked by a complex pathogenesis and limited treatment options. Herein, we conducted single-cell RNA sequencing (scRNA-seq) on the spleen and cervical draining lymph nodes (CDLNs) of both normal and experimental autoimmune uveitis (EAU) mice and found common alterations in celluar composition and transcriptional regulation occurred throughout the EAU process. Moreover, we identified activator protein-1 (AP-1) as a pivotal disease-related molecule in the pathogenesis of EAU. Inhibiting AP-1 alleviated symptoms of EAU and reduced the retina infiltration of T helper 17 cells (Th17) and Th1 cells. Additionally, following treatment with the AP-1 inhibitor, both the spleen and CDLNs showed decreased Th17 and Th1 cell proportions. Meanwhile, in vitro studies revealed that treatment with AP-1 inhibitor reduced the level of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-23 (IL-23), two pivotal molecules implicated in the Th17 cell pathogenicity, during EAU. The adoptive transfer experiment also showed that inhibiting AP-1 in CD4+ T cells suppressed their ability to elicit EAU. Altogether, our study demonstrates that AP-1 might involved in EAU pathogenesis by supporting Th17 cell pathogenicity via the GM-CSF/IL-23 feedback loop. Thus, AP-1 inhibition might be a novel treatment strategy for uveitis.

Immunoregulatory effects of traditional Chinese medicine and its ingredients on psoriasis

Psoriasis is an immune-mediated inflammatory skin disease involving the activation and regulation of various immune cells. A proportion of psoriasis patients remain unresponsive to conventional therapies or targeted drugs, highlighting the urgent need for novel therapeutic strategies. In addition, although many conventional immunosuppressants are effective in the treatment of psoriasis, they may cause various side effects. Traditional Chinese Medicine (TCM) represents a potential drug candidate, with a rich history of traditional use and a vast array of pharmacological options. In particular, TCM may serve as an alternative or complementary therapy of psoriasis with potentially less side effects. In this review, we focus on immune cells, including dendritic cells, neutrophils, macrophages, myeloid-derived suppressor cells, Th17, regulatory T (Treg) cells, and γδ T cells. We provide an overview of the roles for these immune cells in the pathogenesis of psoriasis and regulatory effects of TCM and its ingredients on them. Additionally, we briefly summarize the clinical research involving treatment of psoriasis with TCM and discuss the existing challenges and limitations in this field.

Exploring the Role of Licorice and Its Derivatives in Cell Signaling Pathway NF-κB and MAPK

Licorice is a therapeutic herb in traditional Chinese herbal medicine. Licorice is considered as an anti-inflammatory agent due to its suppression and inhibition of inflammatory pathways. Licorice has many bioactive compounds such as glycyrrhetinic acid, glycyrrhizin, liquiritigenin, and isoliquirtigenin which are principally accountable for its therapeutic benefits. These bioactive components reduce inflammation by preventing the activation of important inflammatory pathways including mitogen-activated protein kinases (MAPKs) and nuclear factor-kappa B (NF-κB). As a result of this tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β) and interleukin-6 (IL-6) are among the proinflammatory cytokines whose production is inhibited. Components present in licorice inhibit the activation by suppressing the IκBα phosphorylation and degradation. Moreover, licorice compounds also attenuate the MAPK signaling cascades by inhibiting the MAPK kinase phosphorylation and downstream MAPKs such as extracellular signal-regulated kinase (ERK), p38 MAPK, and c-Jun N-terminal kinase (JNK). The present review focuses on the current understanding of licorice effect on the NF-κB and MAPK inflammatory cell signaling pathways at molecular level. Furthermore, emerging evidence suggested that licorice-derived bioactive compounds may attenuate the molecular mechanism which is associated with inflammation, providing the additional insights into the therapeutic potential. Further studies explained the precise molecular mechanism at the cellular level underlying the licorice anti-inflammatory effect and potential application in managing inflammatory disorders. In conclusion, licorice has a complex mode of action and is a valuable natural anti-inflammatory. Its natural origin and effectiveness in clinical applications make it an intriguing topic for additional study. As licorice becomes more widely used in medicine, future research should focus on refining its formulations to optimize therapeutic advantages.

Combining Metagenomics, Network Pharmacology and RNA-Seq Strategies to Reveal the Therapeutic Effects and Mechanisms of Qingchang Wenzhong Decoction on Inflammatory Bowel Disease in Mice

Background

Inflammatory bowel disease (IBD) is a chronic and recurrent inflammatory disease that lacks effective treatments. Qingchang Wenzhong Decoction (QCWZD) is a clinically effective herbal prescription that has been proven to attenuate intestinal inflammation in IBD. However, its molecular mechanism of action has not been clearly elucidated.

Purpose

We aimed to probe the mechanism of QCWZD for the treatment of IBD.

Methods

The dextran sulfate sodium (DSS)-induced mouse model of IBD was used to identify the molecular targets involved in the mechanism of action of QCWZD. Metagenomics sequencing was utilized to analyze the differences in gut microbiota and the functional consequences of these changes. Network pharmacology combined with RNA sequencing (RNA-seq) were employed to predict the molecular targets and mechanism of action of QCWZD, and were validated through in vivo experiments.

Results

Our results demonstrated that QCWZD treatment alleviated intestinal inflammation and accelerated intestinal mucosal healing that involved restoration of microbial homeostasis. This hypothesis was supported by the results of bacterial metagenomics sequencing that showed attenuation of gut dysbiosis by QCWZD treatment, especially the depletion of the pathogenic bacterial genus Bacteroides, while increasing the beneficial microorganism Akkermansia muciniphila that led to altered bacterial gene functions, such as metabolic regulation. Network pharmacology and RNA-seq analyses showed that Th17 cell differentiation plays an important role in QCWZD-based treatment of IBD. This was confirmed by in vivo experiments showing a marked decrease in the percentage of CD3+CD4+IL-17+ (Th17) cells. Furthermore, our results also showed that the key factors associated with Th17 cell differentiation (IL-17, NF-κB, TNF-α and IL-6) in the colon were significantly reduced in QCWZD-treated colitis mice.

Conclusion

QCWZD exerted beneficial effects in the treatment of IBD by modulating microbial homeostasis while inhibiting Th17 cell differentiation and its associated pathways, providing a novel and promising therapeutic strategy for the treatment of IBD.

Baicalin and probenecid protect against Glaesserella parasuis challenge in a piglet model

Glaesserella parasuis (G. parasuis) induces vascular damage and systemic inflammation. However, the mechanism by which it causes vascular damage is currently unclear. Baicalin has important anti-inflammatory, antibacterial and immunomodulatory functions. In this study, we explored the ability of baicalin and probenecid to protect against G. parasuis challenge in a piglet model. Sixty piglets were randomly divided into a control group; an infection group; a probenecid group; and 25 mg/kg, 50 mg/kg and 100 mg/kg baicalin groups. The probenecid group and the 25 mg/kg, 50 mg/kg and 100 mg/kg baicalin groups were injected intramuscularly with 20 mg/kg body weight (BW) probenecid and 25 mg/kg BW, 50 mg/kg BW and 100 mg/kg BW baicalin, respectively. All piglets except those from the control group were injected intraperitoneally with 1 × 108 CFU of G. parasuis. The control group was injected intraperitoneally with TSB. The results showed baicalin and probenecid protected piglets against G. parasuis challenge, improved body weight and decreased temperature changes in piglets. Baicalin and probenecid attenuated IL-1β, IL-10, IL-18, TNF-α and IFN-γ mRNA levels in the blood for 48 h, inhibited the production of the nucleosides ATP, ADP, AMP and UMP from 24 to 72 h, reduced Panx-1/P2Y6/P2X7 expression, weakened NF-kB, AP-1, NLRP3/Caspase-1 and ROCK/MLCK/MLC signalling activation, and upregulated VE-cadherin expression in the blood vessels of piglets challenged with G. parasuis. Baicalin and probenecid alleviated pathological tissue damage in piglets induced by G. parasuis. Our results might provide a promising strategy to control and treat G. parasuis infection in the clinical setting.

Natural Product-Derived Compounds Targeting Keratinocytes and Molecular Pathways in Psoriasis Therapeutics

Psoriasis is a chronic autoimmune inflammatory skin disorder that affects approximately 2-3% of the global population due to significant genetic predisposition. It is characterized by an uncontrolled growth and differentiation of keratinocytes, leading to the formation of scaly erythematous plaques. Psoriasis extends beyond dermatological manifestations to impact joints and nails and is often associated with systemic disorders. Although traditional treatments provide relief, their use is limited by potential side effects and the chronic nature of the disease. This review aims to discuss the therapeutic potential of keratinocyte-targeting natural products in psoriasis and highlight their efficacy and safety in comparison with conventional treatments. This review comprehensively examines psoriasis pathogenesis within keratinocytes and the various related signaling pathways (such as JAK-STAT and NF-κB) and cytokines. It presents molecular targets such as high-mobility group box-1 (HMGB1), dual-specificity phosphatase-1 (DUSP1), and the aryl hydrocarbon receptor (AhR) for treating psoriasis. It evaluates the ability of natural compounds such as luteolin, piperine, and glycyrrhizin to modulate psoriasis-related pathways. Finally, it offers insights into alternative and sustainable treatment options with fewer side effects.

Network pharmacology and gut microbiota insights: unraveling Shenling Baizhu powder's role in psoriasis treatment

Background: Psoriasis, a chronic skin condition characterized by systemic inflammation and altered gut microbiota, has been a target of Traditional Chinese Medicine (TCM) for centuries. Shenling Baizhu Powder (SLBZP), a TCM formulation, holds promise for treating inflammatory diseases, but its specific role in psoriasis and impact on gut microbiota is not fully understood. Objective: This study aims to elucidate the mechanism of SLBZP in treating psoriasis, integrating component analysis, network pharmacology, and experimental validation in mice models. Methods: We commenced with a detailed component analysis of SLBZP using liquid chromatograph and mass spectrometer (LC-MS). Network pharmacology analysis was used to predict the potential action targets and pathways of SLBZP in psoriasis. An in vivo experiment was conducted with psoriasis mice models, treated with SLBZP. Therapeutic effects were assessed via symptomatology, histopathology, and immunohistochemical analysis. Gut microbiota composition was analyzed using 16S rRNA gene sequencing. Results: A total of 42 main components and quality markers were identified, primarily from licorice and ginseng, including flavonoids, saponins and other markers. PPI topology analysis showed that TNF, IL-6, IL-1β, TP53 and JUN were the core DEPs. 168 signaling pathways including lipid and atherosclerosis, AGE-RAGE signaling pathway, IL-17 signaling pathway and Th17 cell differentiation were enriched by KEGG. SLBZP demonstrated significant therapeutic effects on psoriasis in mice, with alterations in skin pathology and biomarkers. Additionally, notable changes in gut microbiota composition were observed post-treatment, indicating a possible gut-skin axis involvement. Conclusion: This research has pinpointed lipid metabolism as a key pathway in the treatment of psoriasis with SLBZP. It explores how SLBZP's modulation of gut microbiota and lipid metabolism can alleviate psoriasis, suggesting that balancing gut microbiota may reduce inflammation mediators and offer therapeutic benefits. This underscores lipid metabolism modulation as a potential new strategy in psoriasis treatment.