Finally, ginsenoside Rg1 inhibits the phosphorylation of PPARγ by downregulating the cyclin-dependent kinase (CDK5) pathway and ultimately reduces Aβ levels by affecting the expression of PPARγ target genes, including APP, BACE1, and IDE, in an AD model established using Aβ1-42-treated primary rat neurons [96]. The gene discussed is BACE1; the disease is Alzheimer disease.