Effect of total glucosides of paeony on the changes of IL-4 and ICAM-1 levels in eczema mouse model serum

Effect of total glucosides of paeony on the changes of IL-4 and ICAM-1 levels in eczema mouse model serum was investigated. A total of 38 KM mice of SPF grade were divided into 3 groups: the control group (n=10), the model group (n=15) and the treatment group (n=13). The pathological model of chronic eczema in mouse right ear was induced using dinitrochlorobenzene acetone solution. Two ears of mice in the control group and the left ear of mice in the model and treatment groups were smeared with acetone as control. The mice in the treatment group were treated by administration with total glucoside of paeony. The changes of IL-4 and ICAM-1 levels were measured using caudal vein blood collection. The mouse ear weight was measured and the relationship among IL-4 and ICAM-1 levels, ear thickness and treatment time was analyzed. Mouse ear thickness in the model group was higher than that in the treatment and control groups (P<0.05). The weight of the mouse right ear in the model and treatment groups was significantly higher than that of the left ear (P<0.05). Furthermore, The IL-4 and ICAM-1 levels of mice in the model group were higher than that in the treatment and control groups (P<0.05). The IL-4 and ICAM-1 levels of mice in the model and treatment groups increased compared to that before modeling (P<0.05). The IL-4 and ICAM-1 levels of mice were positively correlated with ear thickness in the model group (r=0.865, P=0.002; r=0.833, P=0.009). In addition, the IL-4 level of mice was positively correlated with the ICAM-1 level in the model group (r=0.812, P=0.014). Finally, IL-4 and ICAM-1 may be involved in the pathologic process of chronic eczema. Therefore, the study showed that the total glucosides of paeony may play a role in the treatment of chronic eczema by regulating the IL-4 and ICAM-1 levels.

1β-Hydroxyalantolactone, a sesquiterpene lactone from Inula japonica, attenuates atopic dermatitis-like skin lesions induced by 2,4-dinitrochlorobenzene in the mouse

CONTEXT

1β-Hydroxyalantolactone (IJ-5) is a sesquiterpene lactone compound isolated from Inula japonica Thunb (Asteraceae). Sesquiterpene lactones have been shown to modulate many processes that influence inflammatory reactions.

OBJECTIVE

The present study examines the protective effect of IJ-5 on atopic dermatitis (AD) in a mouse model induced by 2,4-dinitrochlorobenzene (DNCB).

MATERIALS AND METHODS

AD-like skin lesions were induced in Balb/c mice by sensitizing once with painting 100 μL of 5% DNCB on their shaved back skin and then challenging with 20 μL of 0.2% DNCB five times on their right ears at 3 d interval starting on day 5 post-sensitization. IJ-5 was administrated intraperitoneally at 10 mg/kg 1 h before each DNCB challenge.

RESULTS

IJ-5 treatment attenuated DNCB-induced dermatitis severity and right ear swelling. The serum levels of IgE, IL-4, and IL-6 in IJ-5-treated mice were reduced by 54.7, 56.5, and 53.0%, respectively, while the mRNA levels of TNFα, IL-1, IL-4, and IL-6 in back skin lesions of IJ-5-treated mice were reduced by 47.7, 61.5, 57.5, and 58.5%, respectively, compared with untreated controls. Histopathological examination showed that IJ-5 treatment decreased DNCB-induced hypertrophy, hyperkeratosis, and infiltration of inflammatory cells in both ear and back skins. Moreover, IJ-5 suppressed the expression of TNFα, IL-1, and IL-6 with IC50 values of 6.58, 9.48, and 7.01 μM, respectively, and inhibited the activation of NF-κB pathway in TNFα-stimulated HaCat cells.

DISCUSSION AND CONCLUSION

The present study demonstrates the protective effects of IJ-5 against AD-like skin inflammation and highlights IJ-5 as a potential therapeutic agent for AD.