These data indicate that a dysregulation in the autophagic pathway is improved by polyphenols through mTOR, AMPK, SIRT1, Ho-1 and JNK/Bcl-2 signaling, and polyphenols also increase the clearance of α synuclein and thereby help in the mitochondrial turnover in PD. The gene discussed is SNCA; the disease is Parkinson disease.