Recently, several studies have found that berberine is a potential neuroprotector for several neurodegenerative pathogenesis, including Parkinson’s disease, Huntington’s diseases and Alzheimer’s disease (AD) through ameliorating the β-amyloids deposition, or enhancing the degradation of mutant huntingtin by autophagic pathway [27–31]. The gene discussed is HTT; the disease is Alzheimer disease.