Experimental Study On The Effect Of Compound Sophora Decoction On Treating Allergic Dermatitis In Rats

ObjectiveTo establish the ACD (Allergic Contact Dermatitis) rats model and explore the mechanism and target spot when curing ACD with Compound Kusheng Antipruritic Ointment.Methods1. Fourteenth SD rats were randomly divided into blank group (only dorsal hair removal in two places) and model group (only establish the ACD model). Rats were sensitized by DNCB on the back skin, and also challenged on the back skin.24 hours after the challenge, the pathological changes was observed by means of HE staining, and the expression levels of TNF-a and IL-4 in serum were detected with ELISA.2. Twenty-eight SD rats were randomly divided into blank group (only dorsal hair removal in two places), model group (only establish the ACD model), treatment group (establish the ACD model and apply Compound Kusheng Antipruritic Ointment), and positive control group (establish the ACD model and apply Mometasone Furoate Cream). The concentration of IL-4, TNF-a and LTB4 in serum were detected by enzyme linked immunosorbent assay(ELISA). The mRNA expression of BLT1, Caspase-14in skin lesion were tested by Real Time-Polymerase Chain Reaction (RT-PCR).Results1. The challenged back skin of the model group showed generalized erythema and swelling. HE staining of skin lesion revealed that there was significant infiltration of inflammatory cells, which was consistent with typical contact dermatitis pathology. It means that the model of allergic contact dermatitis (ACD) on rats’ back has been successfully established; The ELISA detection results showed that the amount of Thl cells increased, while the amount of Th2 cells decreased, It means that the Thl ACD is more likely to be induced by DNCB.2. The comparison of LTB4 and BLT1 concentration showed that the quantity of LTB4 in blood serum and the BLT1 mRNA expression in the skin lesion of the model group were significantly higher than that of the blank group (P<0.05). The LTB4 concentration of the treatment group and the positive control group were significantly lower than that of the model group (P<0.01), and the results of these two groups showed no statistical difference (P>0.05).3. The experimental results showed that the Caspase-14 mRNA expression in the skin lesion of the model group were significantly higher than that of the blank group (P<0.05). The Caspase-14 mRNA expression of the treatment group, the positive control group, and the model group showed no statistical difference (P>0.05).Conclusion1. The model of allergic contact dermatitis (ACD) on rats’ back has been successfully established.2. Compound Kusheng Antipruritic Ointment can suppress the LTB4-BLT path and then control the inflammatory reaction.3. Experiment shows that the Caspase-14 expression increases significantly after the normal skin barrier is damaged. This reveals that the external stimuli on the damaged skin will increase the expression of Caspase-14 through signal transmission. This mechanism is helpful to the recovery of skin barrier.