Efficacy of kampo medicine in treating atopic dermatitis: an overview

Mechanisms of intestinal pharmacokinetic natural product-drug interactions

The growing co-consumption of botanical natural products with conventional medications has intensified the need to understand potential effects on drug safety and efficacy. This review delves into the intricacies of intestinal pharmacokinetic interactions between botanical natural products and drugs, such as alterations in drug solubility, permeability, transporter activity, and enzyme-mediated metabolism. It emphasizes the importance of understanding how drug solubility, dissolution, and osmolality interplay with botanical constituents in the gastrointestinal tract, potentially altering drug absorption and systemic exposure. Unlike reviews that focus primarily on enzyme and transporter mechanisms, this article highlights the lesser known but equally important mechanisms of interaction. Applying the Biopharmaceutics Drug Disposition Classification System (BDDCS) can serve as a framework for predicting and understanding these interactions. Through a comprehensive examination of specific botanical natural products such as byakkokaninjinto, green tea catechins, goldenseal, spinach extract, and quercetin, we illustrate the diversity of these interactions and their dependence on the physicochemical properties of the drug and the botanical constituents involved. This understanding is vital for healthcare professionals to effectively anticipate and manage potential natural product-drug interactions, ensuring optimal patient therapeutic outcomes. By exploring these emerging mechanisms, we aim to broaden the scope of natural product-drug interaction research and encourage comprehensive studies to better elucidate complex mechanisms.

Hochuekkito exerts the anti-allergic effects via activating regulatory T cells in a murine model of contact hypersensitivity

Hochuekkito (HET) is a Kampo prescription, used for the clinical treatment of skin diseases such as atopic dermatitis (AD), in Japan. Oral administration of HET exerts anti-allergic effects in an experimental dermatitis mice model and in patients with atopic dermatitis; however, the mechanism underlying the anti-allergic effects of HET is still unclear. Therefore, we investigated the immunopharmacological properties of the anti-allergic actions of HET using a 2,4,6-trinitrochlorobenzene (TNCB)-induced murine contact hypersensitivity (CHS) model and adoptive cell transfer experiments. Oral administration of HET (1.4 g/kg) exhibited anti-allergic effects in a TNCB-induced CHS model via activation of Tregs; this activation was observed even without antigen sensitization in donor mice. Activation was dependent on the duration of HET administration and required at least 4 days of dosing. In addition, the anti-allergic effects of HET through the activation of Tregs were not antigen specific. Flow cytometry results indicated that the proportion of CD4+CD25+Foxp3+ cells in the splenic lymphocytes increased after oral administration of HET. Therefore, oral administration of HET induced both inducible regulatory T cells (iTregs) and thymus-derived naturally occurring regulatory T cells (nTregs). Ginseng radix and Bupleuri radix were involved in the anti-allergic actions of HET through the induction and/or activation of Tregs; Bupleuri radix participated in the activation of nTregs. In conclusion, our findings suggest that HET exerts the anti-allergic effects through the induction and/or activation of Tregs. These findings elucidate the usefulness of HET as an immunomodulator.

Desire for Alternative Treatment Options in Patients with Atopic Dermatitis in Japan: Results of a Web-Based Cross-Sectional Study (AD-JOIN Study)

INTRODUCTION

Treatment satisfaction in patients with atopic dermatitis (AD) has been investigated in several studies, but the desire for alternative treatment options is unclear and has not been previously evaluated. We conducted a cross-sectional, web-based survey aimed at evaluating the desire for alternative treatment options in adults with AD from a patient registry in Japan.

METHODS

Main eligibility criteria were adults aged ≥ 18 years with AD who were receiving treatment with topical corticosteroids (TCS) and not systemic therapy. Questionnaires included the Patient Oriented Eczema Measure (POEM) and pruritus Numeral Rating Scale. The proportion of patients with a desire for an alternative treatment option was assessed, overall (Overall Desire) and by specific type of alternative treatment option (Specific Desire), including change in medication, hospital transfer, and complementary and alternative medicine (CAM) use. Patient background factors associated with desire were evaluated using multivariate logistic regression.

RESULTS

Of the 1500 patients included in the analysis, 91.5% (n = 1372) had an Overall Desire, with the most common Specific Desire being a change in medication (n = 1213, 80.9%), followed by CAM (n = 593, 39.5%) and hospital transfer (n = 429, 28.6%). Dissatisfaction with current treatment was significantly (p < 0.05) associated with Overall Desire and Specific Desire (p < 0.001 each). Severe disease according to POEM was significantly associated with Overall Desire and a change in medication (p < 0.001 each).

CONCLUSIONS

A high proportion of Japanese patients with AD being treated with TCS had a desire for alternative treatment options. The desire was greatly affected by patients' satisfaction with their current treatment and perception of disease severity. These findings highlight the importance of assessing patients' satisfaction or perception of disease severity, and facilitating early discussions between patient and doctor on their available treatment options, including new treatment options.

Berberine induces anti-atopic dermatitis effects through the downregulation of cutaneous EIF3F and MALT1 in NC/Nga mice with atopy-like dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease with severe pruritus. Berberine, a naturally occurring isoquinoline alkaloid, has anti-inflammatory effects. This study investigated the effects and molecular mechanisms of berberine on AD-like symptoms in mice. In this study, NC/Nga mice with atopy-like dermatitis (dermatitis mice), fibroblast and mast cells were used. In dermatitis mice, intermittent oral administrations of berberine 3 times a week for 12 days inhibited skin symptom, itching, cutaneous infiltration of eosinophils and mast cells, and the expression of cutaneous eotaxin, macrophage migration inhibitory factor (MIF) and IL-4. Berberine also attenuated IL-4/MIF-induced eotaxin in fibroblasts and allergen-induced MIF and IL-4 in mast cells. In mast cells, the GeneChip® microarray showed that antigen increased the expression of EIF3F and MALT1, inhibited by berberine. The siRNAs for them inhibited the expression of MIF and IL-4 in antigen-stimulated mast cells. These results suggest that berberine improves AD-like symptoms through the inhibition of the eotaxin and pro-inflammatory cytokine expression and the related inflammatory cell recruitment. It is also suggested that the downregulation of EIF3F and MALT1 by berberine is involved in suppressing the cytokine expression. Taken together, berberine or berberine-containing crude drugs are expected to contribute to the improvement of AD symptoms.

Current treatments for atopic dermatitis in Japan

The goal of a treatment regimen for atopic dermatitis is to reach and maintain a state where the patient exhibits mild symptoms or an absence of symptoms, and the patient should not experience disturbance during daily activities. The basis of a treatment regimen for atopic dermatitis is topical therapy, and currently there exist topical corticosteroids, tacrolimus and delgocitinib. Using these, proactive therapy is performed as maintenance therapy after remission induction therapy. However, in cases of moderate to severe atopic dermatitis, topical drugs alone cannot induce remission and systemic therapies such as cyclosporin, ultraviolet therapy, and dupilumab should be used in combination. In particular, dupilumab has many advantages such as high efficacy, relatively few adverse reactions, and ease of use in elderly patients with severe atopic dermatitis. In this review, we present a treatment algorithm for atopic dermatitis that emphasizes the importance of maintaining remission after induction of remission, and summarizes the characteristics of current medication therapy for atopic dermatitis in Japan.

Therapeutic Benefit in Allergic Dermatitis Derived from the Inhibitory Effect of Byakkokaninjinto on the Migration of Plasmacytoid Dendritic Cells

Dendritic cells (DCs) are well known to be essential immunocytes involved in innate and adaptive immunity. DCs are classified as conventional dendritic cells (cDCs) and plasmacytoid dendritic cells (pDCs). Recently, the accumulation of pDCs in inflamed tissues and lymphoid tissues has been considered to be a possible contributing factor in the development of immunological diseases, but little is known about the pathophysiological roles of pDCs in immunological diseases. To date, many studies have demonstrated that many kinds of Kampo formulas can regulate immunological reactions in human immune diseases. Thus, we screened Kampo formulas to identify an agent that inhibits pDC migration. Furthermore, we investigated the therapeutic effects of these formulas on a murine DNFB-induced allergic contact dermatitis model. Bone marrow-derived pDCs (BMpDCs) were derived from the bone marrow cells of BALB/c mice in a culture medium with Flt3 ligand. The effects of Kampo formulas on BMpDC migration were evaluated by assessing the number, velocity, and directionality of BMpDCs chemotaxing toward the more concentrated side of a chemokine (C-C motif) ligand 21 (CCL21) gradient. The Kampo formulas that exerted inhibitory effects on pDC migration were orally administered to DNFB-induced allergic contact dermatitis model mice. Byakkokaninjinto reduced the number of migrated BMpDCs and suppressed the velocity and directionality of BMpDC migration in a chemotaxis assay. Gypsum Fibrosum and Ginseng Radix, which are components of byakkokaninjinto, obviously suppressed the velocity of BMpDC migration. Furthermore, Gypsum Fibrosum significantly suppressed the directionality of BMpDC migration. In DNFB-induced allergic contact dermatitis model mice, byakkokaninjinto markedly abrogated ear swelling in late-phase allergic reactions. In conclusions, byakkokaninjinto, which has an inhibitory effect on pDC migration, was able to prevent the occurrence of allergic contact dermatitis, suggesting that pDCs were involved in the onset of allergic contact dermatitis in the mouse model. Therefore, byakkokaninjinto is anticipated to be a therapeutic agent for disorders related to pDC migration.

Functionalized Textile Based Therapy for the Treatment of Atopic Dermatitis

Atopic dermatitis (AD) is a common chronic inflammatory skin condition characterized by intense puritus and skin dryness. The pathogenesis for AD has not been fully understood to date. Complementary therapies are very popular as effective treatment for AD among clinical practitioners. This study presents a comprehensive review of published works associated with textiles-based complementary therapies for AD treatment such as wet-wrap dressing, functionalized textiles, and the application of hydrogel techniques in the textile industry to provide a better understanding of the development and design of new textiles-based transdermal therapies.

Efficient Use of a Crude Drug/Herb Library Reveals Ephedra Herb As a Specific Antagonist for TH2-Specific Chemokine Receptors CCR3, CCR4, and CCR8

Chemokine receptors CCR3 and CCR4 are preferentially expressed by TH2 cells, mast cells, and/or eosinophils, all of which are involved in the pathogenesis of allergic diseases. Therefore, CCR3 and CCR4 have long been highlighted as potent therapeutic targets for allergic diseases. Japanese traditional herbal medicine Kampo consists of multiple crude drugs/herbs, which further consist of numerous chemical substances. Recent studies have demonstrated that such chemical substances appear to promising sources in the development of novel therapeutic agents. Based on these findings, we hypothesize that Kampo-related crude drugs/herbs would contain chemical substances that inhibit the cell migration mediated by CCR3 and/or CCR4. To test this hypothesis, we screened 80 crude drugs/herbs to identify candidate substances using chemotaxis assay. Among those tested, Ephedra Herb inhibited the chemotaxis mediated by both CCR3 and CCR4, Cornus Fruit inhibited that mediated by CCR3, and Rhubarb inhibited that mediated by CCR4. Furthermore, Ephedra Herb specifically inhibited the chemotaxis mediated by not only CCR3 and CCR4 but CCR8, all of which are selectively expressed by TH2 cells. This result led us to speculate that ephedrine, a major component of Ephedra Herb, would play a central role in the inhibitory effects on the chemotaxis mediated by CCR3, CCR4, and CCR8. However, ephedrine exhibited little effects on the chemotaxis. Therefore, we fractionated Ephedra Herb into four subfractions and examined the inhibitory effects of each subfraction. As the results, ethyl acetate-insoluble fraction exhibited the inhibitory effects on chemotaxis and calcium mobilization mediated by CCR3 and CCR4 most significantly. In contrast, chloroform-soluble fraction exhibited a weak inhibitory effect on the chemotaxis mediated by CCR8. Furthermore, maoto, one of the Kampo formulations containing Ephedra Herb, exhibited the inhibitory effects on the chemotaxis mediated by CCR3, CCR4, and CCR8. Taken together, our data suggest that these crude drugs/herbs might be useful sources to develop new drugs targeting TH2-mediated allergic diseases.

Clinical Search for Undiagnosed Mesenteric Phlebosclerosis at Outpatient Departments Specializing in Herbal (Kampo) Medicine

OBJECTIVE

Mesenteric phlebosclerosis (MP) is a disease characterized by calcification of the mesenteric vein, which causes chronic mesenteric ischemia. Recently, the long-term intake of gardenia fruit ('Sanshishi' in Japanese) has been attracting attention as a possible cause. Usually, only advanced, severe MP cases get reported. However, we suspected that some latent cases of this disease may exist. We performed this study in order to determine the prediagnostic cases at our outpatient departments of herbal (Kampo) medicine, with particular attention paid to the initial changes, such as any slight color change of the colon, as shown in colonoscopy.

METHODS

We recommend colonoscopy and computed tomography (CT) scans for patients with a long-term history of taking herbal medicines containing gardenia fruit. Clinical examinations were performed upon receiving patients' consent from December 2013 to November 2014.

RESULTS

Of the 103 patients who took gardenia fruit long-term, 29 agreed to be checked for MP. 14 patients underwent colonoscopy. Four patients were confirmed to have MP due to the presence of fibrotic deposition of the colonic membrane on histological inspection. Twenty-one patients underwent abdominal CT screening. Characteristic calcification of the mesenteric vein was observed on CT scans in 2 patients. All 4 MP patients took Kampo formulas containing gardenia fruit for more than 6.8 years. The other patients did not develop MP, despite long-term gardenia fruit intake.

CONCLUSION

We detected the latent and undiagnosed MP cases. All diagnoses were made while paying careful attention to any slight changes in colonoscopy and CT scans.