Abstract
Growth factors and cytokines (referred to collectively hereafter as GFs) control cell
growth, proliferation, and differentiation via a network of inter and intracellular
signaling pathways. There are striking parallels between the pathways involved in
skin wound healing and those implicated in photoaging of the skin. In recent years,
topical and injectable GFs have emerged as an intriguing therapeutic modality that
can be harnessed for aesthetic and medical purposes. This article provides a review
of available evidence for the role in skin regeneration of topical GFs, and of injectable
GFs contained in autologous platelet-rich plasma (PRP). It presents data from recent
studies of GFs, offers a discussion of their potential to serve as antiaging actives,
and includes safety considerations. As studies of injectable GFs typically assume
preexisting familiarity with PRP protocols and the theory behind them, explanatory
notes are provided. An assessment is provided of the evidence gaps that exist currently
between experimental observations regarding GFs and their proven clinical benefits.
Data of evidence levels II and III support the use for skin rejuvenation of topical
GFs derived from sources including secretions or lysate of human dermal fibroblasts,
and secretions of the snail Cryptomphalus aspersa. GFs with associated stem cell proteins, secreted by human dermal fibroblasts under
hypoxic stress, can accelerate skin healing after laser resurfacing. In vitro and
animal studies, small case series of PRP-treated patients and one prospective clinical
study of its variant, platelet-rich fibrin matrix (PRFM), suggest the value of injectable
GFs for skin rejuvenation. However, data of higher power are required to expand this
proof of concept into an evidence-based paradigm. The clinical applications of topical
and injectable GFs are promising, and remain to be fully defined. With continued study,
data of higher evidence level can be accrued and formulations can be developed that
offer optimal clinical efficacy, safety, tolerability, and stability. Better understanding
of the mechanism of action of GFs can potentially advance our general understanding
of dermal signaling pathways, and hence of hyaluronic acid and other alloplastic fillers;
and allow the development of protocols for synergistic combination of GFs with other
skin rejuvenation modalities.
Keywords
growth factors - cosmeceuticals - platelet-rich plasma - skin aging - skin rejuvenation
- cytokines - platelet-rich fibrin matrix - transforming growth factor-β - platelet-derived
growth factor - vascular endothelial growth factor
