Abstract:Objective To evaluate the effect the of arbutin on chloasma in guinea pig model and explore the possible mechanism. Methods Fifty female guinea pigs of SPF grade were randomized into five groups by weight including a blank group, a model group, a low-dose arbutin group, a middle-dose arbutin group, and a high-dose arbutin group with 10 in each group. Except for the blank group, intramuscular injection of progesterone was adopted in all of the guinea pigs to induce chloasma model. The guinea pigs were killed after treated with different doses of arbutin ointment and hydroquinone cream for 30 d. A piece of skin from the lesion was collected for the detection of tyrosine content, SOD activity and MDA content; another piece of the lesion was collected for pathological observation after HE staining and for immunohistochemical detection. Results SOD activity obviously increased, MDA and tyrosine content reduced in the skin of chloasma in all the arbutin groups, which were more obvious in the medium-dose arbutin group. In all the arbutin groups the area of melanin in the skin of chloasma reduced and the color became lighter, especially in the medium-dose arbutin group. Conclusions Arbutin has a good effect on experimental chloasma guinea pig model, probably through increasing SOD activity and reducing MDA and tyrosine content.