HPGD and skin aging: The results showed that apart from CXCR2, other targets (AR, BCEH, HPGD and PI3) were all linked to up-regulation of autophagy (Figure 7A–7L), and down-regulation of Phospholipase D signaling pathway, which suggested AAK compounds may exert therapeutical effect on skin aging via inhibiting autophagy process and activating the Phospholipase D signaling.