The therapeutical effect and mechanism of acitretin in scleroderma mice model

Objective To study the therapeutical effect of acitretin for systemic scleroderma(SSc) in the mouse model.Peripheral blood IL-17,IL-10,IL-6 and TGF-β1,which were Th17/Treg related factors were examined to explore the possible mechanism of acitretin.Methods 24 female BALB/c mice were randomly divided into control group,SSc group and acitretin group.SSc group and acitretin group were given subcutaneous injections of bleomycin for 4 weeks,and acitrein group were given acitretin 6 mg/(kg.d) orally for 4 weeks.4 weeks later,pathological changes of the skin and lung of the mice were detected.Enzyme-linked immunosorbent assay(ELISA) was used to measure the levels of IL-17,IL-10,IL-6 and TGF-β1 in the serum.Results Skin thickness,skin inflammation score,lung inflammation score of acitretin group were significantly lower than the SSc group [(140.25 ±20.24) μm vs(191.88±40.95) μm,(0.75± 0.01) scores vs(2.00±0.76) scores,(1.38±0.52) scores vs(2.00±0.92) scores,P 0.05).Serum IL-17,IL-6,IL-10 of acitretin group were significantly lower than the SSc group [(50.69 ±11.72) pg/mL vs(66.89±16.62) pg/mL,(85.77± 12.06) pg/mL vs(118.68±22.62) pg/mL,(57.65±21.74) pg/mL vs(131.07±22.52) pg/mL,P 0.05].Serum TGF-β1 levels of three groups showed no significant differences.Conclusion Acitretin significantly improves symptoms of skin and lungs in the scleroderma mice model,and its mechanism may related with Th17/Treg balance.