Mechanism of Longevity Extension of<i>Caenorhabditis elegans</i>Induced by Pentagalloyl Glucose Isolated from Eucalyptus Leaves

The multicellular model organism Caenorhabditis elegans (C. elegans) was used to identify the anti-aging effect of pentagalloyl glucose (PGG) isolated from Eucalyptus leaves at four different concentrations. For 160 μM PGG, the median lifespan of C. elegans was found to increase by 18%, and the thermal stress resistance was also increased. The anti-aging effect of PGG did not cause side effects on the physiological functions including the reproduction, pharyngeal pumping rate, age pigments accumulation, and locomotion ability. The life extension induced by PGG was found to rely on genes daf-16, age-1, eat-2, sir-2.1, and isp-1 but did not rely on genes mev-1 and clk-1. These findings suggested that the insulin/IGF-1 signaling pathway, dietary restriction, Sir-2.1 signaling, and mitochondrial electron transport chain became partly involved with the mechanism of lifespan extension mediated by PGG. Our results provided an insight into the mechanism of longevity extension mediated by PGG in C. elegans, which might be developed into a new generation of multitarget drug to prolong lifespan.