astragalin and Dermatitis--Atopic

Topics: Animals; Anti-Inflammatory Agents; Behavior, Animal; Cell Line; Chloroform; Dermatitis, Atopic; Dinitrochlorobenzene; Filaggrin Proteins; Humans; Interferon-gamma; Interleukin-6; Kaempferols; Mice; Plant Extracts; Pyrus; RAW 264.7 Cells; Skin

We have previously shown that persimmon leaf extract and its major flavonoid constituent, astragalin, inhibited histamine release by basophils and that oral administration of these substances prior to the onset into an atopic dermatitis (AD) model mouse, NC/Nga, prevented development of dermatitis.. This study was designed to assess the clinical therapeutic effect of persimmon leaf extract and astragalin in NC/Nga mice suffering from dermatitis and the dose-response preventive effects of persimmon leaf extract on dermatitis and transepidermal water loss (TEWL).. The efficacy of persimmon leaf extract or astragalin in NC/Nga mice was judged by measurement of skin severity, scratching behaviour, serum IgE levels or TEWL.. Oral administration of persimmon leaf extract (250 mg kg(-1)) or astragalin (1.5 mg kg-1) for 4 weeks into NC/Nga mice with overt dermatitis resulted in a decrease in the severity of the condition. The preventive effect of persimmon leaf extract on the dermatitis was dose-dependent and continuous intake of persimmon leaf extract significantly decreased its onset and development. In addition, TEWL was also suppressed at a persimmon leaf extract dose of 250 mg kg(-1). No significant adverse reaction by these substances could be observed.. These observations suggest that persimmon leaf extract or the flavonoid astragalin may be alternative substances for the management of AD.

Topics: Administration, Oral; Animals; Dermatitis, Atopic; Diospyros; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Evaluation, Preclinical; Drugs, Chinese Herbal; Flavonoids; Kaempferols; Mice; Mice, Inbred Strains; Phytotherapy; Plant Leaves; Water Loss, Insensible

We previously found that persimmon leaf extract contains antiallergic substances that inhibit histamine release by human basophilic cell line KU812 in response to cross-linkage of FcepsilonRI.. The purpose of this study was to identify substances in the persimmon leaf extract that are responsible for the effect and to examine their in vivo effects on the allergic mouse model.. HPLC analysis of persimmon leaf extract was done to measure its content. Inhibitory activity of persimmon leaf extract or its major constituent of flavonoids (astragalin) on the histamine release by KU812 cells was examined. To investigate the effects of these substances in vivo, models of passive cutaneous anaphylaxis and atopic dermatitis mice (NC/Nga) were used.. Persimmon leaf extract or astragalin inhibited histamine release from KU812 in response to cross-linkage of FcepsilonRI. Oral intake of both substances dose dependently inhibited passive cutaneous reactions. Moreover, oral administration of these substances to NC/Nga atopic dermatitis-model mice led to a striking suppression of the development of dermatitis, scratching behavior, and serum IgE elevation. Histologic analyses revealed that infiltration of inflammatory cells, especially degranulated mast cells, thickening of the epidermis, and prominent hyperkeratosis, were significantly reduced. Immunologic studies showed that the capacity of spleen T cells to produce both IL-4 and IL-13, but not IFN-gamma, was downregulated by means of oral intake of these substances.. This study demonstrates a novel activity of astragalin and the dramatic effect of persimmon leaf extract and astragalin on atopic dermatitis-model mice.

Topics: Administration, Oral; Animals; Basophils; Cells, Cultured; Dermatitis, Atopic; Flavonoids; Histamine Release; Humans; Immunoglobulin E; Interleukin-13; Interleukin-4; Kaempferols; Mice; Mice, Inbred Strains; Passive Cutaneous Anaphylaxis; Plant Extracts; Plant Leaves; Receptors, IgE; Solanaceae; Spleen; T-Lymphocytes