sh-Oligopeptide-2 or rh-Oligopeptide-2 — (See Insulin-Like Growth Factor 1 (IGF-1) is claimed to stimulate cell proliferation and wound healing. As we age the levels of IGF decline and this decline makes the dermal fibroblasts less responsive. IGF-1 possesses the ability to stimulate both epithelial cells and fibroblasts to increase proliferation rates. It is considered to be the most important growth factor for anti-aging due to its ability to activate cell growth. There is also a study that indicates EGF and IGF1 work in synergy to promote keratinocyte proliferation. They act as chemical messengers between cells, turning essential biological activities "on" and "off," and are involved in increasing the rate of collagen and elastin production.