Injectable Growth Factors and Facial Rejuvenation
Costas Papageorgiou MD, London January 2015
Topical and injectable growth factors have emerged as intriguing therapies with an expanding potential in skin rejuvenation. The aim of administering growth factors is to replenish the skin’s own depleted levels and to upregulate the activity of cells responsible for collagen production, thereby slowing or even reversing the manifestations of skin aging.
Growth factors may be applied topically in cosmeceutical formulations, or injected in the autologous form of Platelet-Rich-Plasma (PRP). PRP is a treatment in which a patient’s own cell biology is used to achieve a process of biostimulation: using the patient’s own growth factors to stimulate regeneration of the skin and dermis.
Platelets are small cell fragments circulating in the blood and when activated they can release vital growth factors and proteins that are important in wound healing as well as tissue repair and regeneration. The primary function of platelets is to control blood loss and promote wound healing via fibrin clot formation. This clot is a reservoir of growth factors which are released into plasma from the activated platelets. There are several parallels between pathways of wound healing and rejuvenation of the aging face: both involve release of key growth factors.
Unlike hormones, the activity of growth factors in confined to the vicinity of their sites of production. The aim of PRP is to concentrate and provide these growth factors directly to the target tissue. Ideally, the concentration of platelets in PRP may be 2 to 4 times the normal platelet concentration in the blood. It is important to stay close to the body’s normal physiological levels, in order to reactivate natural regenerative processes without overstimulation.
The preparation of PRP involves withdrawal of 15 to 20 ml of blood from the patient followed by centrifugation and isolation of a fraction that is rich in activated platelets, plasma proteins and a selection of white cells. Injection of this natural concentrate into the face allows direct and sustained delivery of growth factors where they can activate fibroblasts and boost new collagen deposition.
PRP is virtually a cocktail of many proteins that collectively stimulate repair and regeneration. There are many growth factors with varying responsibilities, however by delivering a powerful cocktail of growth factors several effects have been noted:
Fibroblast stimulation and collagen production (dermal regeneration)
Increased turnover of keratinocytes (improved skin elasticity and epidermal regeneration)
Increased blood flow and nutrient delivery (angiogenesis)
Enhanced anti-oxidant activity (downregulation of free radicals)
Although the use of PRP for indications such as skin rejuvenation is off FDA (USA) labelling, clinical studies have shown promising outcomes. Histological findings support clinical observations of soft tissue augmentation and improvement of skin texture and elasticity. These data have expanded the clinical applications of PRP into remodelling of scars or acceleration of healing after facelift procedures.
Outcomes depend on the biostimulatory potential and skin quality of each patient. Usually, 2-3 treatments are required to achieve noticeable results. The growth factors are administered via multiple injections at different levels of the skin-dermis. Topical or local anaesthetics can be administered if necessary. As with any aesthetic intervention redness, swelling, slight pain, bruising or all these signs can occur in the treatment area. These side effects usually subside in a few hours to a few days. Post care instructions will need to be followed to optimise outcomes.
Balancing the efficacy and safety of this treatment is essential as different preparation protocols can affect the concentration-activation of growth factors and therefore the control mechanisms linked to their safe application. Even when specific protocols are used, the concentration and activation status of the growth factors can vary greatly among techniques and even within a single technique. In addition, platelet concentrations can vary from day to day in PRP produced from a single individual, depending on factors such as diet, general health, medications (like coagulants), and exercise. Super-concentration or other strategies aiming to maximize cellular proliferation is not recommended.
A better understanding of the mechanisms of isolation and release of biological factors will allow standardization of protocols regarding the number of treatments and treatment intervals in facial rejuvenation.