diospyros and Dermatitis--Atopic

Atopic dermatitis (AD) is a common chronic inflammatory skin disease, affecting 10-20% of individuals worldwide. Therefore, the discovery of drugs for treating AD is an attractive subject and important to human health. Diospyros kaki and Diospyros kaki (D. kaki) folium exert beneficial effects on allergic inflammation. However, the effect of D. kaki calyx on AD remains elusive. The present study evaluated the effects of an aqueous extract of D. kaki calyx (AEDKC) on AD-like skin lesions using mouse and keratinocyte models. We used a mouse AD model by the repeated skin exposure of house dust mite extract [Dermatophagoides farinae extract (DFE)] and 2,4-dinitrochlorobenzene (DNCB) to the ears. In addition, to determine the underlying mechanism of its operation, tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ)-activated keratinocytes (HaCaT) were used. Oral administration of AEDKC decreased AD-like skin lesions, as demonstrated by the reduced ear thickness, serum immunoglobulin E (IgE), DFE-specific IgE, IgG2a, histamine level and inflammatory cell infiltration. AEDKC inhibited the expression of pro-inflammatory cytokines and a chemokine via downregulation of nuclear factor-κB and signal transducer and activator of transcription 1 in HaCaT cells. On examination of the AD-related factors in vivo and in vitro, it was confirmed that AEDKC decreased AD-like skin lesions. Taken together, the results suggest that AEDKC is a potential drug candidate for the treatment of AD.

Topics: Animals; Anti-Inflammatory Agents; Dermatitis, Atopic; Dinitrochlorobenzene; Diospyros; Disease Models, Animal; Female; Immunoglobulin G; Keratinocytes; Mice; Mice, Inbred BALB C; Plant Extracts; Pyroglyphidae; Skin

Atopic dermatitis, a chronic relapsing and pruritic inflammation of the skin also thought to be involved in, or caused by immune system destruction is an upsetting health problem due to its continuously increasing incidence especially in developed countries. Mast cell infiltration in atopic dermatitis skin lesions and its IgE-mediated activation releases various cytokines and chemokines that have been implicated in the pathogenesis of atopic dermatitis. This study was aimed at investigating synergistic anti-inflammatory, anti-pruritic and anti-atopic dermatitis effects of Diospyros lotus leaf extract (DLE) and Muscat bailey A grapefruit stem extract (GFSE) in atopic dermatitis-like induced skin lesions in mice. Combinations of DLE and GFSE inhibited TNF-α and IL-6 production more than DLE or GFSE in PMA plus calcium ionophore A23187-activated HMC-1 cells. DLE and GFSE synergistically inhibited compound 48/80-induced dermal infiltration of mast cells and reduced scratching behavior than DLE or GFSE. Furthermore, DLE and GFSE synergistically showed a stronger ameliorative effect in skin lesions by reducing clinical scores; dermal infiltration of mast cells; ear and dorsal skin thickness; serum IgE and IL-4 production in atopic dermatitis-like mice. Collectively, these results suggest that DLE and GFSE synergistically exhibit anti-atopic dermatitis effects in atopic dermatitis-like skin lesions in mice.

Topics: Animals; Citrus paradisi; Dermatitis, Atopic; Diospyros; Mast Cells; Mice; Plant Extracts; Plant Stems

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