Perspective Platelet-rich plasma: a healing virtuoso (original) (raw)
Growth-promoting action and growth factor release by different platelet derivatives
Platelets, 2013
Platelet derivatives are commonly used in wound healing and tissue regeneration. Different procedures of platelet preparation may differentially affect growth factor release and cell growth. Preparation of platelet-rich fibrin (PRF) is accompanied by release of growth factors, including platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF) and transforming growth factor b1 (TGFb1), and several cytokines. When compared with the standard procedure for platelet-rich plasma (PRP), PRF released 2-fold less PDGF, but 415-fold and 42-fold VEGF and TGFb1, respectively. Also, the release of several cytokines (IL-4, IL-6, IL-8, IL-10, IFNg, MIP-1a, MIP-1b and TNFa) was significantly increased in PRF-conditioned medium (CM), compared to PRP-CM. Incubation of both human skin fibroblasts and human umbilical vein endothelial cells (HUVECs) with PRF-derived membrane (mPRF) or with PRF-CM enhanced cell proliferation by 42-fold (p50.05). Interestingly, PRP elicited fibroblast growth at a higher extent compared to PRF. At variance, PRF effect on HUVEC growth was significantly greater than that of PRP, consistent with a higher concentration of VEGF in the PRF-CM. Thus, the procedure of PRP preparation leads to a larger release of PDGF, as a possible result of platelet degranulation, while PRF enhances the release of proangiogenic factors.
The therapeutic basis of platelet-rich plasma use in medicine is derived from the growth factor content and provisional matrix provided by the platelets themselves. This chapter briefly reviews the platelet research which led to the conceptual development of PRP as a treatment and also the early history of its use. An overview of platelet structure and function is provided to enhance the clini-cian's understanding of the cell biology behind PRP therapy. The 2 major growth factors in PRP (PDGF and TGFb) are also discussed. Finally, a review of the experimental PRP literature (in vitro and animal studies) is presented, which describes the evidence for use of PRP in tendon/ligament, bone, and joints. Standardization of PRP use remains a challenging prospect due to the number of variables involved in its preparation and administration. It may be that individually tailored PRP protocols are actually more beneficial for our patients—only time and further research will bear this out. Origins and Overview of PRP Use in Medicine As recently as forty years ago, platelets were considered to be exclusively hemostatic cells. Today we know that platelets actually perform myriad diverse functions. The conventional paradigm of limited platelet function began to shift in 1974, as the pathogenesis of atherosclerosis was beginning to be unraveled. Researchers studying the proliferation of smooth muscle cells in the vascular intima knew that 10 % serum was crucial to support cell growth in culture, but did not know which component of serum was responsible for the observed anabolic
International journal of implant dentistry, 2016
The development of platelet-rich fibrin (PRF) drastically simplified the preparation procedure of platelet-concentrated biomaterials, such as platelet-rich plasma (PRP), and facilitated their clinical application. PRF's clinical effectiveness has often been demonstrated in pre-clinical and clinical studies; however, it is still controversial whether growth factors are significantly concentrated in PRF preparations to facilitate wound healing and tissue regeneration. To address this matter, we performed a comparative study of growth factor contents in PRP and its derivatives, such as advanced PRF (A-PRF) and concentrated growth factors (CGF). PRP and its derivatives were prepared from the same peripheral blood samples collected from healthy donors. A-PRF and CGF preparations were homogenized and centrifuged to produce extracts. Platelet and white blood cell counts in A-PRF and CGF preparations were determined by subtracting those counts in red blood cell fractions, supernatant ac...
Orthopedic Research and Reviews
Platelet-rich plasma (PRP) contains many growth factors, such as FGF, which induces the production of type I collagen, and VEGF, which induces neovascularization, all of which are important in bone healing. This study aimed to evaluate the effect of PRP administration on type I collagen production, VEGF expression, and neovascularization in rat models following femoral bone implants using K-wire. Methods: An experimental randomized control study was conducted on 24 white male rats (Rattus norvegicus) in the Wistar strain that underwent K-wire implantation, where PRP was administered to the treatment groups. The amount of type I collagen was measured by immunohistochemistry VEGF expression using sandwich ELISA, and neovascularization by histopathological examination. Results: The amount of type I collagen in the treatment group (50->150/field of view) was significantly higher than the control group (0-99/field of view; p=0.003). VEGF expression in the treatment groups was significantly higher than controls: 10.90±4.47 and 2.29 ±0.92, respectively (p=0.006). Mean number of new vessels formed on fibrotic capsules in the treatment groups was significantly (p=0.007) higher than the control groups (2.69±1.03 vs 0.67±0.52). Conclusion: The use of PRP significantly increased type I collagen production, VEGF expression, and neovascularization in rat models, elucidating the potential of PRP to be used in clinical settings to enhance the bone-healing process.
Autologous platelets as a source of proteins for healing and tissue regeneration
Thrombosis and Haemostasis, 2003
SummaryPlatelets are known for their role in haemostasis where they help prevent blood loss at sites of vascular injury. To do this, they adhere, aggregate and form a procoagulant surface leading to thrombin generation and fibrin formation. Platelets also release substances that promote tissue repair and influence the reactivity of vascular and other blood cells in angiogenesis and inflammation. They contain storage pools of growth factors including PDGF, TGF-β and VEGF as well as cytokines including proteins such as PF4 and CD40L. Chemokines and newly synthesised active metabolites are also released. The fact that platelets secrete growth factors and active metabolites means that their applied use can have a positive influence in clinical situations requiring rapid healing and tissue regeneration. Their administration in fibrin clot or fibrin glue provides an adhesive support that can confine secretion to a chosen site. Additionally, the presentation of growth factors attached to p...
PDGF and VEGF Levels in Platelet-Rich Plasma
The Journal of Dentists, 2013
PDGF and VEGF are two of the most potent mitogen for connective tissue, its secretion appears to be particularly important when the source is Platelet Rich Plasma (PRP), hence the latter leading role in tissue regeneration. ELISA PDGFBB levels in PRP, Platelet Poor Plasma (PPP) and exudates, were determined in 32 healthy subjects before and 24 hours after ingestion of Aspirin (ASA) and Clopidogrel (CLO). Results: PDGFBB baseline levels were 10.6 ± 1.9 ng / ml (PPP), 12.12 ± 2.5 ng / ml (PRP) and 10.84 ± 1.68 ng / ml (exudate) While after treatment with PDGFBB ASA concentrations were at 8.96 ± 1.4 ng / ml (PPP), 11.36 ± 1.48 ng / ml (PRP), 11.11 ± 1.14 ng / ml (exudate) and the Clopidogrel were 8.53 ± 0.59 ng / ml (PPP), 9.65 ± 1.17 ng / ml (PRP) and 8.51 ± 0.75 ng / ml (exudate) . VEGF basal values were 973.9 ± 590.3 pg / ml (PPP), 1184.2 ± 288.4 pg / ml (PRP), 1069.3 ± 192.3 pg / ml (exudate). After treatment with ASA VEGF values ??were at 1439.5 ± 117.4 pg / ml (PPP), 1802.3 ± 123...
The use of autologous blood-derived growth factors in bone regeneration
Clinical cases in mineral and bone metabolism : the official journal of the Italian Society of Osteoporosis, Mineral Metabolism, and Skeletal Diseases, 2011
Platelet-rich plasma (PRP) is defined as a portion of the plasma fraction of autologous blood having platelet concentrations above baseline. When activated the platelets release growth factors that play an essential role in bone healing such as Platelet-derived Growth Factor, Transforming Growth Factor-β, Vascular Endothelial Growth Factor and others.Multiple basic science and in vivo animal studies agree that PRP has a role in the stimulation of the healing cascade in ligament, tendon, muscle cartilage and in bone regeneration in the last years PRP had a widespread diffusion in the treatment of soft tissue and bone healing.The purpose of this review is to describe the biological properties of platelets and its factors, the methods used for producing PRP, to provide a background on the underlying basic science and an overview of evidence based medicine on clinical application of PRP in bone healing.
Platelet-Rich Plasma: The Choice of Activation Method Affects the Release of Bioactive Molecules
BioMed Research International, 2016
Platelet-Rich Plasma (PRP) is a low-cost procedure to deliver high concentrations of autologous growth factors (GFs). Platelet activation is a crucial step that might influence the availability of bioactive molecules and therefore tissue healing. Activation of PRP from ten voluntary healthy males was performed by adding 10% of CaCl2, 10% of autologous thrombin, 10% of a mixture of CaCl2+ thrombin, and 10% of collagen type I. Blood derivatives were incubated for 15 and 30 minutes and 1, 2, and 24 hours and samples were evaluated for the release of VEGF, TGF-β1, PDGF-AB, IL-1β, and TNF-α. PRP activated with CaCl2, thrombin, and CaCl2/thrombin formed clots detected from the 15-minute evaluation, whereas in collagen-type-I-activated samples no clot formation was noticed. Collagen type I produced an overall lower GF release. Thrombin, CaCl2/thrombin, and collagen type I activated PRPs showed an immediate release of PDGF and TGF-β1that remained stable over time, whereas VEGF showed an inc...
Biomedicine
Introduction and Aim: Activated autologous platelet-rich plasma (aaPRP) is becoming a popular therapy to accelerate healing in the field of plastic surgery. Platelets, which are abundant in aaPRP, can release many growth factors including platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF). This study aims to examine the plasma levels of PDGF and VEGF in healthy subjects after intravenous administration of aaPRP. Materials and Methods: Nine healthy patients with no prior history of metabolic disease were divided into two groups (control and experiment group). The treatment group which consists of six patients received intravenous aaPRP treatment. The preparation of aaPRP starts with the collection of 24 mL of whole blood in sodium citrate tubes followed a two-step centrifugation procedure and subsequent chemical activation. aaPRP was then administered intravenously to patients. Meanwhile, the control group received no intervention. Venous blood samp...