Parishin from <i>Gastrodia elata</i> Extends the Lifespan of Yeast via Regulation of Sir2/Uth1/TOR Signaling Pathway

Parishin is a phenolic glucoside isolated from Gastrodia elata, which is an important traditional Chinese medicine; this glucoside significantly extended the replicative lifespan of K6001 yeast at 3, 10, and 30 μM. To clarify its mechanism of action, assessment of oxidative stress resistance, superoxide dismutase (SOD) activity, malondialdehyde (MDA), and reactive oxygen species (ROS) assays, replicative lifespans of sod1, sod2, uth1, and skn7 yeast mutants, and real-time quantitative PCR (RT-PCR) analysis were conducted. The significant increase of cell survival rate in oxidative stress condition was observed in parishin-treated groups. Silent information regulator 2 (Sir2) gene expression and SOD activity were significantly increased after treating parishin in normal condition. Meanwhile, the levels of ROS and MDA in yeast were significantly decreased. The replicative lifespans of sod1, sod2, uth1, and skn7 mutants of K6001 yeast were not affected by parishin. We also found that parishin could decrease the gene expression of TORC1, ribosomal protein S26A (RPS26A), and ribosomal protein L9A (RPL9A) in the target of mTOR(definition)-inhibiting drug studied for extending healthspan and lifespan." style="text-decoration:underline dotted; text-underline-offset:2px; cursor:help;">rapamycin(definition) (TOR) signaling pathway. Gene expression levels of RPS26A and RPL9A in uth1, as well as in uth1, sir2 double mutants, were significantly lower than those of the control group. Besides, TORC1 gene expression in uth1 mutant of K6001 yeast was inhibited significantly. These results suggested that parishin exhibited antiaging effects via regulation of Sir2/Uth1/TOR signaling pathway.