Danggui buxue tang inhibits 2,4-dinitrochlorobenzene: induced atopic dermatitis in mice

Abstract

Danggui Buxue Tang (DBT) is a herbal decoction that has been used in Chinese medicine to enhance qi and blood circulation. Previously, we found that DBT can suppress allergy-related asthma in mice, leading us to hypothesize that DBT might ameliorate allergy disease. In this study, we evaluated whether DBT can attenuate atopic dermatitis (AD) symptoms and have an anti-inflammatory effect on AD-like mice. The dorsal skin of female mice was shaved and sensitized cutaneously (skin smear) with 1-chloro-2,4-dinitrobenzene. Mice were then given various doses of DBT from days 14 to 29 cutaneously. DBT treatment suppressed ear swelling and skin inflammation and decreased mast cell and eosinophil infiltration into skin and ear tissue. DBT also inhibited levels of IgE and Th2-associated cytokine levels in serum. These results demonstrate that cutaneous administration of DBT reduced the development of AD-like skin lesions in mice.

Figure 1

A summary of the development of AD-like skin lesions in DNCB-treated mice. The dorsal skin of mice was shaved and treated with topical 0.5% DNCB on days 1–3. Next, the mice were challenged with 1% DNCB on days 14, 17, 20, 23, 26, and 29. AD-like mice were treated with topical Danggui Buxue Tang (DBT) on days 14–27. Finally, mice were sacrificed on day 30.

Figure 2

Clinical features of AD-like skin lesions treated topically with DBT. (a) Normal control mice (N); sensitized control mice (S); sensitized mice topically treated with 3 g/kg DBT (HD3) or 10 g/kg DBT (HD10). Ear thicknesses were also calculated (b). n = 8 mice per group for all groups. Data are presented as means ± SEM. ^* P < 0.05, ^** P < 0.01 versus sensitized control mice.

Figure 3

The effects of DBT on eosinophil infiltration in the ears. Ear sections were stained with H&E and analyzed for eosinophil infiltration in normal control mice (a); sensitized control mice (b); 3 g/kg DBT (HD3, c) or 10 g/kg DBT (HD10, d) (100x magnification); n = 8 mice per group for all groups.

Figure 4

The effects of DBT on eosinophil infiltration in skin. Skin sections were stained with H&E and analyzed for eosinophil infiltration in normal control mice (a); sensitized control mice (b); 3 g/kg DBT (HD3, c) or 10 g/kg DBT (HD10, d) (100x magnification, and amplified graph is 200x); n = 8 mice per group for all groups. Black arrows indicate eosinophils.

Figure 5

The effects of DBT on mast cell infiltration in ear tissue. Ear sections were stained with toluidine blue to analyze mast cell infiltration in normal control mice (a); sensitized control mice (b); 3 g/kg DBT (HD3, c) or 10 g/kg DBT (HD10, d) (100x magnification); n = 8 mice per group for all groups. Arrows indicate mast cells. The mast cells were measured under 10–15 high-power fields (HPFs) (e). Data are presented as means ± SEM. ^* P < 0.05, ^** P < 0.01 versus sensitized control mice.

Figure 6

The effects of DBT on mast cell infiltration in skin tissue. Skin sections were stained with toluidine blue to analyze mast cell infiltration in normal control mice (a); sensitized control mice (b); 3 g/kg DBT (HD3, c) or 10 g/kg DBT (HD10, d) (100x magnification, and amplified graph is 200x); n = 8 mice per group for all groups. Arrows indicate mast cells. The mast cells were measured under 10–15 high-power fields (HPFs) (e). Data are presented as means ± SEM. ^* P < 0.05, ^** P < 0.01 versus sensitized control mice.

Figure 7

Effect of DBT on levels of serum IL-4 (a), TNF-α (b), serum antibodies IgE (c), IgG1 (d), and IgG2a (e). Serum was centrifuged and collected; then the cytokine and antibody levels were evaluated by ELISA. Data are presented as means ± SEM. ^* P < 0.05, ^** P < 0.01 versus sensitized control mice.

Figure 8

Effect of DBT on cytokine levels of spleen cells. The cells were stimulated with 2 μg/mL concanavalin A (Con A) for 2 days. The supernatants were collected and assayed the levels of IFN-γ (a), IL-4 (b), and IL-5 (c). Data are presented as means ± SEM. ^* P < 0.05, ^** P < 0.01 versus sensitized control mice.