Extract of Polygala tenuifolia Alleviates Stress-Exacerbated Atopy-Like Skin Dermatitis through the Modulation of Protein Kinase A and p38 Mitogen-Activated Protein Kinase Signaling Pathway

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.

A novel strategy on the study of whole intestinal metabolic profiles for Polygalae Radix before and after processing

INTRODUCTION

Relieving toxicity and enhancing a calming effect after processing Polygalae Radix (PR) are widely known. Aromatic carboxylic acids (ACAs) may be crucial processed products. However, due to the limited detection methods for ACAs, the whole metabolic profiles via intestinal bacteria are still not very clear.

OBJECTIVE

Designing a novel strategy for the detection of ACAs and tracking the whole metabolic profiles before and after processing PR.

MATERIALS AND METHODS

The stable-isotope labelling derivatisation (SILD) method based on multidimensional ultra-high performance liquid chromatography coupled with a mass spectrometer (UHPLC-MS) technology and UNIFI-pathway mode was firstly designed to systematically study the metabolisms of all the drug-derived ingredients ranging from m/z 100 to 2000 in processing PR via intestinal bacteria. Firstly, the SILD with UHPLC coupled with a triple-quadrupole MS technology was designed to trace eight ACA metabolites of the processed PR with intestinal bacteria. Additionally, the UHPLC coupled with a quadrupole time-of-flight MS with UNIFI-pathway mode was adopted to monitor relatively big metabolites.

RESULTS

The metabolism mechanism of ACAs (eight kinds) and the relatively big molecular metabolites (98 kinds) were deeply traced in PR, PR with refined honey (HP), and PR with licorice (LP) via the intestinal bacteria. Totally 106 intact metabolic profiles of drug-derived ingredients were presented. Importantly, the influence of LP on the metabolism of compounds after incubation of intestinal bacteria was greater than that of HP.

CONCLUSION

This research provides a comprehensive and systematic guidance for further study on in vivo metabolisms of the processed PR.

Development of an online UPLC-PDA-ESI-Q-TOF-MS-LOX-FLD system for rapid screening of anti-inflammatory compounds in Polygala tenuifolia Willd

In this study, the first ultra-high performance liquid chromatography-photo-diode array-electrospray ionization-quadrupole-time-of-flight-mass spectrometry-lipoxygenase-fluorescence detector (UPLC-PDA-ESI-Q-TOF-MS-LOX-FLD) online system was developed for the identification and evaluation of anti-inflammatory active ingredients in Polygala tenuifolia Willd. Using this system, the UPLC fingerprints, mass fragments and LOX-binding peak profiles in the samples were rapidly and simultaneously obtained. A total of 101 compounds were isolated and identified and 38 compounds (11 oligosaccharide esters, nine xanthones, 17 saponins, and one glycosyloxyflavone) showed strong LOX-binding activity. Six compounds were selected to study their LOX-binding ability, and the results indicated that the content of the six compounds had a good linear relationship with the LOX-binding ability, and it was found that the substitution position, the type of substituent and the number of glycosyl groups all had a certain influence on the LOX-binding ability of the compounds. The LOX-binding activities of 10 compounds were verified by the surface plasmon resonance (SPR) technique and the activity results were consistent with the online system. After validation, we identified 7 active compounds that combined with LOX to exert anti-inflammatory effects for the first time. All the results fully demonstrate the efficiency, stability and reliability of the online system and this work provides an exemplary and useful method for the rapid screening of potential anti-inflammatory active compounds in P. tenuifolia and other traditional Chinese medicines. At the same time, it provides a new direction for screening small molecule inhibitors of enzymes like LOX.

Management of Atopic Dermatitis Via Oral and Topical Administration of Herbs in Murine Model: A Systematic Review

Over the past few decades, complementary and alternative medicine (CAM) using herbs, or their active constituents have garnered substantial attention in the management of a chronic and relapsing inflammatory skin disorder called atopic dermatitis (AD), particularly in attenuating disease recurrence and maintaining long-term remission. In Eastern Asian countries including China, Korea and Taiwan, herbal medicine available in both topical and oral preparation plays a significant role in treating skin diseases like AD as they possibly confer high anti-inflammatory properties and immunomodulatory functions. Conventional murine models of AD have been employed in drug discovery to provide scientific evidence for conclusive and specific pharmacological effects elicited by the use of traditional herbs and their active constituents. Coupled with the goal to develop safe and effective novel therapeutic agents for AD, this systematic review consists of a summary of 103 articles on both orally and topically administered herbs and their active constituents in the murine model, whereby articles were screened and selected via a specialized framework known as PICO (Population, Intervention, Comparator and Outcome). The objectives of this review paper were to identify the efficacy of oral and topical administered herbs along with their active constituents in alleviating AD and the underlying mechanism of actions, as well as the animal models and choice of inducer agents used in these studies. The main outcome on the efficacy of the majority of the herbs and their active constituents illustrated suppression of Th2 response as well as improvements in the severity of AD lesions, suppression of Immunoglobulin E (IgE) concentration and mast cell infiltration. The majority of these studies used BALB/c mice followed by NC/Nga mice (commonly used gender–male; commonly used age group – 6–8 weeks). The most used agent in inducing AD was 2, 4-Dinitrochlorobenzene (DNCB), and the average induction period for both oral and topical administered herbs and their active constituents in AD experiments lasted between 3 and 4 weeks. In light of these findings, this review paper could potentially assist researchers in exploring the potential candidate herbs and their active constituents using murine model for the amelioration of AD.

Gyogamdan, a Traditional Medicine Prescription, Ameliorated Dermal Inflammation and Hyperactive Behavior in an Atopic Dermatitis Mouse Model Exposed to Psychological Stress

Psychological stress (PS) plays a significant role as an aggravating factor in atopic dermatitis (AD). The traditional medicine prescription, Gyogamdan, has been used to treat chest discomfort and mood disorders caused by PS. This study investigated the effects of an ethanolic extract of Gyogamdan (GGDE) on stress-associated AD models and the underlying mechanisms. 2,4-Dinitrochlorobenzene- (DNCB-) treated BALB/c mice were exposed to social isolation (SI) stress. The effects of orally administered GGDE (100 or 500 mg/kg) were evaluated by ELISA, western blotting, and an open field test (OFT). SI stress exaggerated the skin inflammation and induced locomotor hyperactivity in the AD mouse model. GGDE reduced the levels of IgE, TNF-α, IL-13, eotaxin, and VEGF and mast cell/eosinophil infiltration and prevented the decreases in the levels of involucrin and loricrin in the skin. GGDE also suppressed the SI-induced increases in corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH), and corticosterone (CORT) in socially isolated AD mice. Furthermore, GGDE reduced traveling distances and mean speed significantly in the OFT. The in vitro experiments were performed using HaCaT, HMC-1, PC12, and BV2 cells. In the TNF-α/IFN-γ- (TI-) stimulated HaCaT cells, GGDE decreased the thymus and activation-regulated chemokine (TARC) and macrophage-derived chemokine (MDC) production significantly by inhibiting p-STAT1 and NF-κB signaling. GGDE also reduced VEGF production in HMC-1 cells stimulated with CRH/substance P (SP) by inhibiting p-ERK signaling pathway. GGDE increased the cell viability significantly and suppressed apoptosis in CORT-stimulated PC12 cells. Moreover, GGDE suppressed the LPS-induced production of NO, TNF-α, IL-1β, and IL-6 in BV2 cells. These results suggest that GGDE might be useful in patients with AD, which is exacerbated by PS.

Atopic dermatitis: new insight into the etiology, pathogenesis, diagnosis and novel treatment strategies

Atopic dermatitis (AD) is the long-lasting chronic inflammatory skin condition associated with cutaneous hyper-reactivity and triggered by environmental factors. The attributes of AD include dry skin, pruritus, lichenification and frequent eczematous abrasions. This has a strong heritable aspect and typically occurs with asthma and allergic rhinitis. The complex pathological mechanism behind AD etiology is epidermal barrier destruction resulting in the lack of filaggrin protein that can induce inflammation and T-cell infiltration. T-helper 2 cell-mediated pathways also bear the responsibility of damage to the epidermal barrier. Certain causative factors for AD include microbial imbalance of skin microbiota, immunoglobulin-E-induced sensitization and neuro-inflammation. Numerous beneficial topical and oral treatments have been available to patients and there are even more drugs in the pipeline for the treatment of AD. Topical moisturizers, corticosteroids, anti-inflammatory agents such as calcineurin inhibitors, phototherapy, cAMP-specific 3, 5 half-cyclic phosphodiesterase 4 inhibitors and systemic immunosuppressants are widely available for AD treatments. Different positions and pathways inside the immune system including JAK-STAT, phosphodiesterase 4, aryl hydrocarbon receptor and T-helper 2 cytokines are targeted by above-mentioned drug treatments. Instead of the severe side effects of topical steroids and oral antihistamines, herbal plants and their derived phytoconstituents are commonly used for the treatment of AD. A clear understanding of AD's cellular and molecular pathogenesis through substantial advancement in genetics, skin immunology and psychological factors resulted in advancement of AD management. Therefore, the review highlights the recent advancements in the understanding of clinical features, etiology, pathogenesis, treatment and management and non-adherence to AD treatment.

Inhibitory effect of carvacrol on lipopolysaccharide-induced memory impairment in rats

Neuroinflammation is an important process underlying a wide variety of neurodegenerative diseases. Carvacrol (CAR) is a phenolic monoterpene commonly used as a food additive due to its antibacterial properties, but it has also been shown to exhibit strong antioxidative, anti-inflammatory, and neuroprotective effects. Here, we sought to investigate the effects of CAR on inflammation in the hippocampus and prefrontal cortex, as well as the molecular mechanisms underlying these effects. In our study, lipopolysaccharide was injected into the lateral ventricle of rats to induce memory impairment and neuroinflammation. Daily administration of CAR (25, 50, and 100 mg/kg) for 21 days improved recognition, discrimination, and memory impairments relative to untreated controls. CAR administration significantly attenuated expression of several inflammatory factors in the brain, including interleukin-1β, tumor necrosis factor-α, and cyclooxygenase-2. In addition, CAR significantly increased expression of brain-derived neurotrophic factor (BDNF) mRNA, and decreased expression of Toll-like receptor 4 (TLR4) mRNA. Taken together, these results show that CAR can improve memory impairment caused by neuroinflammation. This cognitive enhancement is due to the anti-inflammatory effects of CAR medicated by its regulation of BDNF and TLR4. Thus, CAR has significant potential as an inhibitor of memory degeneration in neurodegenerative diseases.

Identification of candidate medicinal herbs for skincare via data mining of the classic Donguibogam text on Korean medicine

Background

Korean cosmetics are widely exported throughout Asia. Cosmetics exploiting traditional Korean medicine lead this trend; thus, the traditional medicinal literature has been invaluable in terms of cosmetic development. We sought candidate medicinal herbs for skincare.

Methods

We used data mining to investigate associations between medicinal herbs and skin-related keywords (SRKs) in a classical text. We selected 26 SRKs used in the Donguibogam text; these referred to 626 medicinal herbs. Using a term frequency-inverse document frequency approach, we extracted data on herbal characteristics by assessing the co-occurrence frequencies of 52 medicinal herbs and the 26 SRKs.

Results

We extracted the characteristics of the 52 herbs, each of which exhibited a distinct skin-related action profile. For example Ginseng Radix was associated at a high-level with tonification and anti-aging, but Rehmanniae Radix exhibited a stronger association with anti-aging. Of the 52 herbs, 46 had been subjected to at least one modern study on skincare-related efficacy.

Conclusions

We made a comprehensive list of candidate medicinal herbs for skincare via data mining a classical medical text. This enhances our understanding of such herbs and will help with discovering new candidate herbs.

Revealing the sedative-hypnotic effect of the extracts of herb pair Semen Ziziphi spinosae and Radix Polygalae and related mechanisms through experiments and metabolomics approach

BACKGROUND

Semen Ziziphi spinosae and Radix Polygalae, two herbs commonly used together in Traditional Chinese Medicine for the treatment of insomnia and anxiety. The study aims to study the sedative-hypnotic effect of the active components of the herbal pair, the possible mechanisms of such effect, and related metabolic pathways in vivo.

METHODS

The sedative and hypnotic effect of the active components (EI30) of the herbal pair was studied by recording influence on the proportion of sleeping within 30 min, sleep latency and sleep length of pentobarbital sodium-induced sleeping on mice. Possible mechanisms of the sedative-hypnotic effect of the active components were investigated by measuring the content of neurotransmitters in the total protein of mice brain tissue. The main chemical compounds of the herbal pair were identified by Liquid Chromatography-Mass Spectrometry (LC-MS). Serum samples of mice were studied, and related differential metabolites between the normal group and model group, and between model group and treatment group were identified by Gas Chromatography Time-Of-Flight Mass Spectrometry (GC-TOF-MS), Principal Components Analysis (PCA), and Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA).

RESULTS

Compared with the control group, high dose EI30 group and the Clonazepam group were with significantly higher proportions of sleep within 30 min (P = 0.027 and 0.005 respectively). Compared with the control group, all of the high, medium and low dose of EI30 groups were with significantly shorter sleep latency (P < 0.01) and prolonged sleeping time (P < 0.01). The herbal pair has good sedative-hypnotic effects, although it is weaker than the effect of Clonazepam. The sedative-hypnotic effect of EI30 is possibly related to the adjustment of neurotransmitters 5-hydroxytryptamine (5-HT), norepinephrine (NE), and dopamine (DA) in the total protein of mice brain tissue. There are five metabolic pathways in vivo most related to the sedative-hypnotic effect of EI30, and they are biosynthesis of valine, leucine, and isoleucine, metabolism of glyceride, metabolism of alanine, aspartic acid and glutamic acid, metabolism of phenylalanine, and metabolism of cysteine and methionine.

CONCLUSIONS

This study reveals the mechanisms of sedative and hypnotic effects of herbal pair Semen Ziziphi spinosae and Radix Polygalae by using metabolomics methods. This study provides a basis for further development and utilization of this herbal pair.

A Natural Compound Mixture Containing Arctigenin, Hederagenin, and Baicalein Alleviates Atopic Dermatitis in Mice by Regulating HPA Axis and Immune Activity

Forsythiae Fructus, Lonicerae Flos, and Scutellariae Radix are medicinal herbs that possess anti-inflammatory and anti-atopic effects. Hence, we investigated the effects of a mixture (ADM), containing arctigenin, hederagenin, and baicalein, which are the main compound from these herbs on atopic dermatitis (AD) skin lesions and the underlying molecular mechanisms. ADM was topically applied to dorsal skin lesions of 2,4-dinitrochlorobenzene- (DNCB-) induced ICR mice, and the expressions of proinflammatory mediators and HPA axis hormones were investigated. The topical application of 0.5% ADM significantly reduced the DNCB-induced symptoms of AD in ICR mice. Histological analysis showed that ADM exerted antiatopic effects by reducing the epidermal thickness and mast cell infiltration into skin lesions. 0.5% ADM attenuated the levels of TNF-α, IFN-γ, IL-4, and VEGF in skin lesions and serum IgE. The production of Th1-/Th2-related cytokines in splenic tissues, including TNF-α, IFN-γ, IL-12, and IL-4, were also decreased by ADM treatment. ADM diminished corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH), and corticosteroid (CORT) production in DNCB-induced mice. In vitro, ADM reduced the productions of TARC/CCL17, MDC/CCL22, IL-6, and ICAM-1 in TNF-α/IFN-γ- (TI-) stimulated HaCaT cells by suppressing the ERK and JNK signaling pathways. In addition, ADM inhibited corticotropin-releasing hormone/substance P- (CRH/SP-) induced VEGF production in HMC-1 cells. These results suggest that ADM may have therapeutic potential in AD by reducing inflammation and attenuating HPA axis activation.

Acacia Polyphenol Ameliorates Atopic Dermatitis in Trimellitic Anhydride-Induced Model Mice via Changes in the Gut Microbiota

We have previously shown that acacia polyphenol (AP), which was extracted from the bark of Acacia mearnsii De Wild, exerts antiobesity, antidiabetic, and antihypertensive effects. In this study, we examined the effect of AP on atopic dermatitis. Trimellitic anhydride (TMA) was applied to the ears of mice to create model mice with atopic dermatitis. The frequency of scratching behavior in the TMA-treated group was significantly higher than that in the control group, and the expression levels of inflammatory markers (tumor necrosis factor-α, interleukin-6, inducible nitric oxide synthase, and cyclooxygenase-2) in the skin also increased. In contrast, both the frequency of scratching behavior and the expression levels of skin inflammatory markers in the AP-treated group were significantly lower than those in the TMA-treated group. The abundances of beneficial bacteria, such as Bifidobacterium spp. and Lactobacillus spp., increased in the AP-treated group compared with the TMA-treated group. Furthermore, the abundances of Bacteroides fragilis and Clostridium coccoides in the gut, which are known for anti-inflammatory properties, increased significantly with AP administration. The present results revealed that AP inhibits TMA-induced atopic dermatitis-like symptoms. In addition, the results also suggested that this effect may be associated with the mechanism of gut microbiota improvement.

The formulae and biologically active ingredients of Chinese herbal medicines for the treatment of atopic dermatitis

Atopic dermatitis (AD) is a common relapsing inflammatory skin disease characterized by severe pruritus that seriously affects the quality of patients' life. There is an increasingly large amount of research demonstrating that traditional Chinese medicine (TCM) including herbal formulae and bioactive ingredients exerts pharmacological effects on atopic dermatitis. It has been a long history of TCM being used to treat atopic dermatitis, especially in preventing disease recurrence, maintaining long-term remission, and reducing disease burden. Nowadays, both of TCM monomer preparations and traditional formulae are still widely used. This review focuses on TCM as well as its bioactive ingredients for the treatment of AD, from the perspectives of animal model construction, pharmacodynamic mechanisms and clinical studies of formulae. To be more specific, the regulation and molecular mechanisms of the herbal formulae and bioactive ingredients of TCM are investigated, and the latest clinical research on TCM formulae is discussed. Furthermore, it provides a summary of the strengths and utilities of TCM, and will be useful for doctors who use Chinese medicine for treatment or researchers who select candidates for clinical treatments or further high-quality clinical studies.