Blood–brain barrier (BBB) homeostasis plays an important role in the treatment of PD, so we roughly verify the interaction between icaritin and BBB-related proteins, such as 12/15-lipoxygenase (12/15-LOX), occludin, claudin-5, and zonula occludens-1 (ZO-1). This evidence concerns the gene CLDN5 and Parkinson disease.