**5.2 Antiaging effect of anthocyanins**

Senescence is a complex physiological process. As early as 1956, Harmon proposed the free radical theory of senescence [55], which believed that the senescence was primarily caused by the attack of free radicals to cell components, and then maintaining the balance of antioxidants and free radical scavengers in the body could delay senescence. There are many studies indicated that proanthocyanidins can obviously reduce the generation of spontaneous MDA in liver and brain tissue of rats and have a significant antagonistic effect in liver lipid peroxidation induced by free radical initiators CCl4, H2O2, and iron ions, lower the depletion of GSH in liver tissue, and reveal obviously anti-lipid peroxidation and free radicals' scavenging ability [56]. The result by Sato et al. reported that GSPE can promote the recovery of cardiac systolic function and decrease the area of myocardial infarction after ischemia reperfusion and the possible mechanism of this proanthocyanidins are related to directly removing peroxide free radicals, enhancing SOD activity, decreasing MDA level, and inhibiting the damage from free radical lipid peroxidation to myocardial membrane [57]. Proanthocyanidins, as natural antioxidants, can alleviate the aging of the body by adjusting the free radical oxidation system [58].
