Pharmacological Inhibition of Stearoyl CoA Desaturase in the Skin Induces Atrophy of the Sebaceous Glands

Stearoyl-CoA desaturase-1(SCD-1) catalyzes the formation of delta9-monounsaturated fatty acids from saturated precursors. Deficiency of SCD-1 in mice causes atrophy of sebaceous glands. We asked whether local pharmacological inhibition of this enzyme in the skin would lead to a similar effect. To this end, we characterized the low-molecular-weight compound XEN103 as a potent and selective inhibitor of SCD-1 activity. The compound blocks microsomal and cellular SCD-1 activity across species with IC50 values in the range of 10-15 nM. Upon topical application to the skin of mice as a 1% solution, XEN103 induces pronounced sebaceous glandatrophy with a rapid onset after a few days of dosing, both sebaceous glandnumbers and size being reduced by 50 to 75%, and without any signs of skin irritation. We show that the effect is due to the local action of the compound on SCD-1 in the skin and occurs in the presence of only minimal plasma exposure. Based on these observations, SCD-1 inhibitors such as XEN103 may provide an opportunity to develop a novel topical therapy for acne, as a disease characterized by overproductionof sebum from hypertrophic sebaceous glands.