MMP1 and skin aging: A detailed investigation showed that CPs first reduce the level of skin oxidation, inhibit the expression of the key transcription factor AP-1 (c-Jun and c-Fos), and then activate the TGF-β/Smad signaling pathway to promote collagen synthesis, inhibit the expression of MMP-1 and MMP-3 to inhibit collagen degradation, and inhibit skin inflammation to alleviate skin aging in mice.