Matrine regulates Th1/Th2 inflammatory responses by inhibiting the Hsp90/NF-κB signaling axis to alleviate atopic dermatitis

Insights from Traditional Chinese Medicine for Restoring Skin Barrier Functions

The skin barrier is essential for maintaining the body's internal homeostasis, protecting against harmful external substances, and regulating water and electrolyte balance. Traditional Chinese Medicine (TCM) offers notable advantages in restoring skin barrier function due to its diverse components, targets, and pathways. Recent studies have demonstrated that active ingredients in TCM can safely and effectively repair damaged skin barriers, reinstating their proper functions. This review article provides a comprehensive overview of the mechanisms underlying skin barrier damage and explores how the bioactive constituents of TCM contribute to skin barrier repair, thereby offering a theoretical framework to inform clinical practices.

Liangxue-Qushi-Zhiyang Decoction Ameliorates DNCB-Induced Atopic Dermatitis in Mice through the MAPK Signaling Pathway Based on Network Pharmacology

The traditional prescription of Liangxue-Qushi-Zhiyang decoction (LQZ) has been demonstrated to be efficacious in treating atopic dermatitis (AD), a chronic inflammatory skin disorder marked by intense itching, redness, rashes, and skin thickening. Nevertheless, there has been an inadequate systematic exploration of the potential targets, biological processes, and pathways for AD treatment through LQZ. The study objective was to evaluate the efficacy and possible mechanism of LQZ in AD mice. In our study, we identified the primary compounds of LQZ, analyzed hub targets, and constructed a network. Subsequently, the predicted mechanisms of LQZ in AD were experimentally studied and validated in vivo, as determined by network pharmacological analysis. A total of 80 serum components of LQZ were identified through ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS), among which 49 compounds were absorbed into the bloodstream. Our results indicated that LQZ targets six putative key factors in the MAPK signaling pathway, which play essential roles in AD, namely, EGFR, p-MAPK1/3, p-MAPK14, IL-1β, IL-6, and TNF-α. We observed spleen coefficient, dermatitis scores, and ear thickness were all downregulated in 2,4-dinitrochlorobenzene (DNCB)-induced mice after LQZ treatment. Histological analysis of the dorsal and ear skin further revealed that LQZ significantly decreased skin inflammation, epidermal thickness, and mast cell numbers compared to the DNCB group. Our study demonstrated the effectiveness of LQZ in reducing epidermal and dermal damage in a mouse model of AD. Furthermore, our findings suggest that downregulating the MAPK signaling pathway could be a potential therapeutic strategy for the treatment of AD.

Therapeutic effects of the Qingre-Qushi recipe on atopic dermatitis through the regulation of gut microbiota and skin inflammation

Accumulating evidence has highlighted a strong association between gut microbiota and the occurrence, development, prevention, and treatment of atopic dermatitis (AD). The regulation of gut microbial dysbiosis by oral traditional Chinese medicine (TCM) has garnered significant attention. In the treatment of AD, the TCM formula Qingre-Qushi Recipe (QRQS) has demonstrated clinical efficacy. However, both the therapeutic mechanisms of QRQS and its impact on gut microbiota remain unclear. Thus, our study aimed to assess the efficacy of QRQS and evaluate its influence on the composition and diversity of gut microbiota in AD animal models. First, we investigated the therapeutic effect of QRQS on AD using two animal models: filaggrin-deficient mice (Flaky tail, ft/ft) and MC903-induced AD-like mice. Subsequently, we explored its influence on the composition and diversity of gut microbiota. Our results demonstrated that QRQS treatment ameliorated the symptoms in both ft/ft mice and MC903-induced AD-like mice. It also reduced the levels of serum IgE and pro-inflammatory cytokines, including IL-1β, IL-4, IL-5, IL-9, IL-13, IL-17A, and TNF-α. Furthermore, QRQS remarkably regulated gut microbiota diversity by increasing Lactobacillaceae and decreasing Bacteroidales. The inflammatory factors in peripheral serum of ft/ft mice showed a close correlation with gut microbiota, as determined using the Spearman correlation coefficient. Additionally, PICRUSt analysis revealed an enrichment in ascorbate and aldarate metabolism, fatty acid metabolism and biosynthesis, and propanoate metabolism in the QRQS group compared to the ft/ft group. Finally, we identified liquiritin as the primary active ingredient of QRQS using ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UPLC-HRMS). Our findings revealed that QRQS improved AD-like symptoms and alleviated skin inflammation in ft/ft and MC903-induced mice. This suggests that modulating the gut microbiota may help elucidate its anti-inflammation activation mechanism, highlighting a new therapeutic strategy that targets the intestinal flora to prevent and treat AD.

Tanshinone IIA protects mouse testes from heat stress injury by inhibiting apoptosis and TGFβ1/Smad2/Smad3 signaling pathway

Heat stress can cause testicular damage and affect male fertility. Tanshinone IIA (TSA) is a monomer substance derived from plants, with antioxidant and anti-apoptotic effects. Whether it can repair testicular damage caused by heat stress is unclear. This study aims to construct a mouse testicular heat stress injury model and intervene with TSA. Various methods such as histopathology, high-throughput sequencing, bioinformatics analysis, and molecular biology were used to investigate whether TSA can alleviate heat stress-induced testicular injury and its mechanism. Results showed that heat stress significantly reduced the diameter of the mouse seminiferous tubules, increased cell apoptosis in the testicular tissue, and significantly decreased testosterone levels. After TSA intervention, testicular morphology and cell apoptosis improved significantly, and testosterone secretion function was restored. High-throughput transcriptome sequencing found that key differentially expressed genes between the HS group and the control and TSA groups clustered in the apoptosis and TGFβ signaling pathways. Using western blot technology, we found that the HS group upregulated TGFβ1/Smad2/Smad3 pathway protein expression, causing cell apoptosis, testicular tissue organic lesions, and affecting testicular secretion function. Through TSA intervention, we found that it can inhibit TGFβ1/Smad2/Smad3 pathway protein expression, thereby restoring testicular damage caused by heat stress. This study confirms that TSA can effectively restore testicular damage caused by heat stress in mice, possibly by inhibiting the TGFβ1/Smad2/Smad3 pathway to suppress apoptosis.

Inhibition of gasdermin D (GSDMD) as a promising therapeutic approach for atopic dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by pruritus, erythema, and skin barrier dysfunction. Gasdermin D (GSDMD) is the key executioner of an inflammatory cell death mechanism known as pyroptosis. However, the role of GSDMD in the pathogenesis of AD remains unclear. Through the analysis of publicly available Gene Expression Omnibus (GEO) datasets, we observed an upregulation of Gsdmd mRNA in the skin tissue of AD patients. Moreover, we delved into the impact of GSDMD deletion and inhibition on AD-like skin lesions using a mouse model induced by the topical application of oxazolone (Oxa). We found that mice lacking GSDMD exhibited relieved AD signs and symptoms in terms of reduced skin thickness, scarring and scratching behavior compared to wild-type mice after induction of AD-like skin lesions. This was associated with decreased infiltration of inflammatory cells, reduced epidermal thickness, and decreased serum levels of IgE and IL-4. Western blot analysis further revealed decreased GSDMD cleavage in the skin of GSDMD knockout mice, and reduced expression of IL-1β and IL-18. Inhibition of GSDMD using the pharmacological agent disulfiram or the herbal compound matrine significantly attenuated the symptoms of AD-like skin lesions in wild-type mice, GSDMD cleavage and pro-inflammatory cytokines were reduced as well. Our results suggest that GSDMD-mediated pyroptosis plays a critical role in the development of AD-like skin lesions, and targeting GSDMD may be a promising therapeutic strategy for AD.

Oxymatrine Alleviates Collagen-Induced Arthritis in Mice by Regulating the Immune Balance of T Cells

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by systemic immunity and autoimmune disorders. We have previously found that oxymatrine (OMT), a natural alkaloid, can alleviate rheumatoid arthritis without knowing whether OMT can alleviate rheumatoid arthritis through gut microbiota. In this study, we found that OMT can alleviate collagen-induced arthritis in mice and reconstruct the immune balance of Th1/Th2, Treg/Th17, and Tfr/Tfh cells. Colon transcriptome gene enrichment analysis indicated that oxymatrine may alleviate collagen induced arthritis in mice through immune system process pathway. Furthermore, OMT significantly altered the gut microbiota variety, changed the composition of microbial colonies, and reshaped the gut microbiota of collagen-induced arthritis (CIA) mice, which may participate in the regulation of the balance of Th1/Th2, Treg/Th17, and Tfr/Tfh cells to alleviate collagen-induced arthritis in mice.