NGF and Alzheimer disease: Kim et al. reported that Re and Rd selectively upregulated the expression of choline acetyltransferase (ChAT) and vesicular acetylcholine transporter (VAChT), which promoted neuron-like cell differentiation and alleviated the symptoms and progression of AD through cell cycle in neuronal differentiation and the nerve growth factor (NGF)-TrkA signaling pathway; moreover, the activity of Rd was superior to that of Re [127].