Inhibitory Effect of Centella asiatica Extract on DNCB-Induced Atopic Dermatitis in HaCaT Cells and BALB/c Mice

Abstract

Atopic dermatitis (AD) is a chronic inflammatory skin disease caused mainly by immune dysregulation. This study explored the anti-inflammatory and immunomodulatory effects of the Centella asiatica ethanol extract (CA) on an AD-like dermal disorder. Treatment with CA inhibited the expression of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in a dose-dependent manner in inflammatory stimulated HaCaT cells by interferon-γ (IFN-γ) and TNF-α-triggered inflammation. Eight-week-old BALB/c mice treated with 2,4-dinitrochlorobenzene (DNCB) were used as a mouse model of AD. In AD induce model, we had two types treatment of CA; skin local administration (80 µg/cm2, AD+CA-80) and oral administration (200 mg/kg/d, AD+CA-200). Interestingly, the CA-treated groups exhibited considerably decreased mast cell infiltration in the ear tissue. In addition, the expression of IL-6 in mast cells, as well as the expression of various pathogenic cytokines, such as TNF-α, IL-4, IL-5, IL-6, IL-10, IL-17, iNOS, COX-2, and CXCL9, was reduced in both AD+CA-80 and AD+CA-200 groups. Collectively, our data demonstrate the pharmacological role and signaling mechanism of CA in the regulation of allergic inflammation of the skin, which supports our hypothesis that CA could potentially be developed as a therapeutic agent for AD.

Chrysin Inhibits NF-κB-Dependent CCL5 Transcription by Targeting IκB Kinase in the Atopic Dermatitis-Like Inflammatory Microenvironment

“…To determine whether the chrysin-induced suppression of CCL5 expression affects the infiltration of inflammatory cells, we performed mast cell staining in DNCB-challenged skin tissue sections using toluidine blue (TB). In accordance with a previous study [ 19 ], DNCB increased the infiltration of TB-positive mast cells; however, this recruitment of TB-positive cells by DNCB was reduced significantly ( p < 0.001, n = 5) upon the repeated application of chrysin ( Figure 6 B). These results suggest that IKK targeting by chrysin led to the suppression of NF-κB activity and reduced NF-κB-regulated CCL5 expression, subsequently suppressing the inflammatory responses and infiltration of inflammatory cells, such as mast cells, in DNCB-induced skin lesions in BALB/c mice.…”

“…A histopathological analysis, which involved hematoxylin and eosin (H&E) staining, and a morphometric analysis showed that the DNCB-induced increase in epidermal and dermal thickenings reduced significantly ( p < 0.001, n = 5) upon the topical application of chrysin ( Figure 5 C). Previous studies have reported that DNCB increases the phosphorylation of p65 NF-κB in BALB/c mice models [ 18 , 19 ]. We also observed that the epidermal levels of phosphorylated p65 NF-κB were high in mice challenged with DNCB; however, the levels decreased substantially upon the topical application of chrysin ( Figure 5 D).…”

Role of Cutaneous Aquaporins in the Development of Xeroderma in Type 2 Diabetes

“…We investigated the presence of local inflammation in the skin of db/db mice. In particular, the mRNA expression levels of TNF-α, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), whose expression is increased due to inflammation [23,24], were evaluated as indices of inflammation.…”

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

“…At the onset of atopic dermatitis, skin inflammation occurs and the expression levels of inflammatory markers, such as TNF-α, IL-6, iNOS, and COX-2, increase [ 26 , 27 ]. We observed the skin condition and the effect of AP on the inflammatory reactions using these expression levels as indexes ( Figure 3 and Figure 4 ).…”