Application of PRP in Skin Rejuvenation & Skin Aging:

Platelet concentration is a rich source of various cytokines and growth factors, which are activated after its injection into the target tissue. Platelets are activated endogenously by coagulation factors (in some methods of preparing PRP, the activated PRP is injected to the tissue). Following their attachment to special receptors on the cell surfaces, some intracellular processes are activated, that facilitate extracellular matrix (ECM) accumulation and improve cell proliferation and differentiation. Tissue regeneration is resulted from cell proliferation, angiogenesis and cell migration.Matrix metalloproteins proteins (MMP) are involved in aging process by degradation of collagen and other extracellular matrix (ECM) proteins, this characteristic can be used to benefit rejuvenation. They can help regeneration of dermis through omission of collagen fragments that are harmful to the dermal connective tissue, and so, provide an appropriate foundation for new collagen deposition. AlsoaPRP (activated PRP) increases the expression of MMP-1 and MMP-3 protein. Thus, aPRP may cause ECM remodeling through stimulating the removal of photo-damaged ECM components and inducing the synthesis of new collagen by fibroblasts, which are in turn proliferated by their stimulation.Another study showed that high concentration of PRP increased type I  collagen, MMP-1 and MMP-2 expression in human skin fibroblasts.
In addition to above mechanisms, improving aging skin through PRP which is a dose-response relationship has been recognized between concentrated platelet and mesenchymal stem cell proliferation.Another mechanism of PRP for skin rejuvenization, is through acceleration of hyaluronic acid production. Hyaluronic acid absorbs water and makes hyaluronic acid matrix swelled which increases skin volume and turgor. It also promotes cell proliferation, extracellular matrix synthesis and helps to the adjustment of the collagen fibers diameter. Overall, it could enhance skin elasticity (41). All these processes and some other unknown ones contribute to tissue rejuvenation through PRP.Platelet Rich Plasma (PRP) is used for stimulation of both superficial and deep dermis layers. For superficial stimulation, the injection must be done in the superficial dermis. The PRP must be injected into the deep dermis or subdermal tissues when using as filler. The superficial injection might be done just like mesotherapy technique in order to improve the skin texture, volume and hydration. The technique is easy to be performed and has no important side-effects. Side-effects might appear from mild bruising and occasional swelling.