Venous ulcers are wounds that are thought to occur due to improper functioning of venous valves, usually of the legs. They are the major cause of chronic wounds, occurring in 70% to 90% of chronic wound cases. The treatment of venous ulcers also entails substantial costs. Autologous platelet rich plasma (PRP) is a simple office based procedure which helps in enhancing the wound healing by releasing many growth factors like platelet derived growth factors, fibroblast derived growth factors and epidermal growth factors.
To study the efficacy of autologous platelet rich plasma in the management of chronic venous ulcer.
12 patients with 17 venous ulcers were treated with PRP and treatment outcome was measured by percentage of improvement in area and volume of the ulcer.
12 patients with 17 ulcers were treated with PRP. The mean age of the patients was 33.5 years (SD 9.82). 10 were males and 2 were females. The mean duration of the healing of the ulcers was in 5.1 weeks (SD 3.1). The mean percentage improvement in the area and volume of the ulcer was 94.7% (SD 11.12) and 95.6% (SD 10.19) respectively.
PRP is safe, simple and effective procedure in treating chronic venous ulcers
Non healing; platelet rich plasma; venous ulcers
Lower extremity ulcers in diabetic patients are difficult to treat. Recently, the use of human blood platelet-derived components in this indication has been raising interest. In this study, we have evaluated the safety and efficacy of the combination of autologous platelet gel (PG) and skin graft for treating large size recalcitrant ulcers. Eight consecutive diabetic patients aged 25 to 82 with nine nonhealing lower extremity ulcers (median size of 50 cm2; range 15–150 cm2) were treated. Skin ulcer was debrided, and the wound was sprayed after 7 to 10 days with autologous platelet-rich plasma and thrombin. Thin split-thickness skin graft with multiple slits was then applied on the wound bed and fixed with staples or cat-gut sutures. There were no adverse reactions observed during the study. Eight out of 9 skin grafts took well. The interval between skin graft and complete wound healing ranged from 2 to 3 weeks in the 8 successful cases. No ulcer recurrence was noted in those patients during the follow-up period of 2 to 19 months. In this study, the combination of autologous platelet gel and skin grafting has proven beneficial to heal large-size recalcitrant ulcers.
Cardiac angiography produces one of the highest radiation exposures of any commonly used diagnostic x ray procedure. Recently, serious radiation induced skin injuries have been reported after repeated therapeutic interventional procedures using prolonged fluoroscopic imaging. Two male patients, aged 62 and 71 years, in whom chronic radiodermatitis developed one to two years after two consecutive cardiac catheterisation procedures are reported. Both patients had undergone lengthy procedures using prolonged fluoroscopic guidance in a limited number of projections. The resulting skin lesions were preceded, in one case, by an acute erythema and took the form of a delayed pigmented telangiectatic, indurated, or ulcerated plaque in the upper back or below the axilla whose site corresponded to the location of the x ray tube during cardiac catheterisation. Cutaneous side effects of radiation exposure result from direct damage to the irradiated tissue and have known thresholds. The diagnosis of radiation induced skin injury relies essentially on clinical and histopathological findings, location of skin lesions, and careful medical history. Interventional cardiologists should be aware of this complication, because chronic radiodermatitis may result in painful and resistant ulceration and eventually in squamous cell carcinoma.
Keywords: catheterisation; angiography; radiation; radiodermatitis; skin injury
Platelet-rich plasma (PRP) contains growth factors that promote tissue regeneration. Previously, we showed that heparin-conjugated fibrin (HCF) exerts the sustained release of growth factors with affinity for heparin. Here, we hypothesize that treatment of skin wound with a mixture of PRP and HCF exerts sustained release of several growth factors contained in PRP and promotes skin wound healing. The release of fibroblast growth factor 2, platelet-derived growth factor-BB, and vascular endothelial growth factor contained in PRP from HCF was sustained for a longer period than those from PRP, calcium-activated PRP (C-PRP), or a mixture of fibrin and PRP (F-PRP). Treatment of full-thickness skin wounds in mice with HCF-PRP resulted in much faster wound closure as well as dermal and epidermal regeneration at day 12 compared to treatment with either C-PRP or F-PRP. Enhanced skin regeneration observed in HCF-PRP group may have been at least partially due to enhanced angiogenesis in the wound beds. Therefore, this method could be useful for skin wound treatment.
angiogenesis inducing agents; endothelial growth factors; fibrin; fibroblast growth factor 2; heparin; neovascularization, physiologic; platelet-derived growth factor; platelet-rich plasma; wound healing
The economic, social and public health burden of chronic ulcers and other compromised wounds are enormous and rapidly increasing with the aging population. The growth factors derived from platelets play an important role in tissue remodeling including neovascularization. Platelet-rich plasma (PRP) has been utilized and studied for the last four decades. Platelet gel and fibrin sealant, derived from PRP mixed with thrombin and calcium chloride, have been exogenously applied to tissues to promote wound healing, bone growth, hemostasis and tissue sealing. In this study we first characterized recovery and viability of as well as growth factor release from platelets in a novel preparation of platelet gel and fibrin matrix, namely, platelet rich fibrin matrix (PRFM). Next, the effect of PRFM application in a delayed model of ischemic wound angiogenesis was investigated. The study for the first-time shows the kinetics of the viability of platelet embedded fibrin matrix. A slow and steady release of growth factors from PRFM was observed. The VEGF released from PRFM was primarily responsible for endothelial mitogenic response via ERK activation pathway. Finally, this preparation of PRFM effectively induced endothelial cell proliferation and improved wound angiogenesis in chronic wounds, providing evidence of probable mechanisms of action of PRFM in healing of chronic ulcers.
platelet rich plasma (PRP); wound healing; angiogenesis; autologous platelet gels; ischemic wounds
Autologous platelet-rich plasma (PRP) may enhance wound healing through the formation of a platelet plug that provides both hemostasis and the secretion of biologically active proteins, including growth factors such as platelet-derived growth factor, transforming growth factor (TGF)-β, TGF-β2, and epidermal growth factor. The release of these growth factors into the wound may create an environment more conducive to tissue repair and could accelerate postoperative wound healing. To our knowledge, there are no reports of combining the use of PRP with curative diabetic foot surgery. This article provides a summary of the literature regarding PRP and wound healing and presents a case of a 49-year-old man with diabetes and a three-month history of a deep, nonhealing plantar hallux wound in which PRP was combined with a first metatarsophalangeal joint arthroplasty. Through the use of the PRP and bioengineered tissue to supplement curative diabetic foot surgery, the patient healed uneventfully at seven weeks.
diabetic; foot surgery; platelet rich plasma; wound
Platelet-rich plasma (PRP) is a new approach to tissue regeneration and it is becoming a valuable adjunct to promote healing in many procedures in dental and oral surgery, especially in aging patients. PRP derives from the centrifugation of the patient's own blood and it contains growth factors that influence wound healing, thereby playing an important role in tissue repairing mechanisms. The use of PRP in surgical practice could have beneficial outcomes, reducing bleeding and enhancing soft tissue healing and bone regeneration. Studies conducted on humans have yielded promising results regarding the application of PRP to many dental and oral surgical procedures (i.e. tooth extractions, periodontal surgery, implant surgery). The use of PRP has also been proposed in the management of bisphosphonate-related osteonecrosis of the jaw (BRONJ) with the aim of enhancing wound healing and bone maturation. The aims of this narrative review are: i) to describe the different uses of PRP in dental surgery (tooth extractions and periodontal surgery) and oral surgery (soft tissues and bone tissue surgery, implant surgery and BRONJ surgery); and ii) to discuss its efficacy, efficiency and risk/benefit ratio. This review suggests that the use of PRP in the alveolar socket after tooth extractions is certainly capable of improving soft tissue healing and positively influencing bone regeneration but the latter effect seems to decrease a few days after the extraction. PRP has produced better results in periodontal therapy in association with other materials than when it is used alone. Promising results have also been obtained in implant surgery, when PRP was used in isolation as a coating material. The combination of necrotic bone curettage and PRP application seem to be encouraging for the treatment of refractory BRONJ, as it has proven successful outcomes with minimal invasivity. Since PRP is free from potential risks for patients, not difficult to obtain and use, it can be employed as a valid adjunct in many procedures in oral and dental surgery. However, further RCTs are required to support this evidence.
PRP; Wound healing; Bone regeneration; Dental surgery; Oral surgery; Tooth extraction; Periodontal surgery; Implant surgery; BRONJ
Peripheral vascular disease and/or diabetic neuropathy represent one of the main etiologies for the development of lower leg and/or diabetic foot ulcerations, and especially after acute trauma or chronic mechanical stress. The reconstruction of such wounds is challenging due to the paucity of soft tissue resources in this region. Various procedures including orthobiologics, skin grafting (SG) with or without negative pressure wound therapy and local random flaps have been used with varying degrees of success to cover diabetic lower leg or foot ulcerations. Other methods include: local or regional muscle and fasciocutaneous flaps, free muscle and fasciocutaneous, or perforator flaps, which also have varying degrees of success.
Patients and methods
This article reviews 25 propeller perforator flaps (PPF) which were performed in 24 diabetic patients with acute and chronic wounds involving the foot and/or lower leg. These patients were admitted beween 2008 and 2011. Fifteen PPF were based on perforators from the peroneal artery, nine from the posterior tibial artery, and one from the anterior tibial artery.
A primary healing rate (96%) was obtained in 18 (72%) cases. Revisional surgery and SG for skin necrosis was performed in six (24%) cases with one complete loss of the flap (4%) which led to a lower extremity amputation.
The purpose of this article is to review the use of PPF as an effective method for soft tissue coverage of the diabetic lower extremity and/or foot. In well-controlled diabetic patients that present with at least one permeable artery in the affected lower leg, the use of PPF may provide an alternative option for soft tissue reconstruction of acute and chronic diabetic wounds.
diabetes mellitus; ulcers; lower leg; foot; propeller perforator flaps
Treatment of gingival recession has become an important therapeutic issue due to increasing cosmetic demand. Multiple surgical procedures have been developed to obtain predictable esthetic root coverage. More specifically, after periodontal regenerative surgery, the aim is to achieve complete wound healing and regeneration of the periodontal unit. A recent innovation in dentistry is the preparation and use of platelet-rich plasma (PRP), a concentrated suspension of the growth factors, found in platelets. These growth factors are involved in wound healing and postulated as promoters of tissue regeneration. This paper reports the use of PRF membrane for root coverage on the labial surfaces of the mandibular anterior teeth. This was accomplished using laterally displaced flap technique with platelet rich fibrin (PRF) membrane at the recipient site.
Plasma rich-derivative (PRF membrane); recession; regeneration; repair
Flaps are currently the predominant method of reconstruction for irradiated wounds. The usefulness of split-thickness skin grafts (STSG) in this setting remains controversial. The purpose of this study is to examine the outcomes of STSGs in conjunction with VAC therapy used in the treatment of irradiated extremity wounds.
The records of 17 preoperatively radiated patients with extremity sarcomas reconstructed with STSGs in conjunction with VAC® therapy were reviewed regarding details of radiation treatment, wound closure, and outcomes.
STSGs healed without complications (>95% of the graft take) in 12 (71%). Minor loss (6% – 20% surface) was noted in 3 patients (17.6%) and complete loss in 2 (11.7%). Two patients (11.7%) required flap reconstructions and 12 (88%) healed without further operative procedures.
Although flap coverage is an established treatment for radiated wounds, STSG in conjunction with liberal utilization of VAC therapy is an alternative for selected patients where acceptable soft tissue bed is preserved. Healing of the preoperatively radiated wounds can be achieved in the vast majority of such patients with minimal need for additional reconstructive operations.
Skin that is exposed to radiation has an impaired ability to heal wounds. This is especially true for whole body irradiation, where even moderate non-lethal doses can result in wound healing deficits. Our previous attempts to administer dermal cells locally to wounds to correct radiation-induced deficits were hampered by poor cell retention. Here we improve the outcome by using biodegradable fibrin microbeads (FMB) to isolate a population of mesenchymal marrow-derived stromal cells (MSC) from murine bone marrow by their specific binding to the fibrin matrix, culture them to high density in vitro and deliver them as MSC on FMB at the wound site. MSC are retained and proliferate locally and assist wounds gain tensile strength in whole body irradiated mice with or without additional skin only exposure. MSC-FMB were effective in 2 different mouse strains but were ineffective across a major histocompatability barrier. Remarkably, irradiated mice whose wounds were treated with MSC-FMB showed enhanced hair regrowth suggesting indirect effect on the correction of radiation-induced follicular damage. Further studies showed that additional wound healing benefit could be gained by administration of G-CSF and AMD3100. Collagen strips coated with haptides and MSCs were also highly effective in correcting radiation-induced wound healing deficits.
Hyperbaric oxygen therapy (HBOT) is the use of 100% oxygen at pressures greater than atmospheric pressure. Today several approved applications and indications exist for HBOT. HBOT has been successfully used as adjunctive therapy for wound healing. Non-healing wounds such as diabetic and vascular insufficiency ulcers have been one major area of study for hyperbaric physicians where use of HBOT as an adjunct has been approved for use by way of various studies and trials. HBOT is also indicated for infected wounds like clostridial myonecrosis, necrotising soft tissue infections, Fournier's gangrene, as also for traumatic wounds, crush injury, compartment syndrome, compromised skin grafts and flaps and thermal burns. Another major area of application of HBOT is radiation-induced wounds, specifically osteoradionecrosis of mandible, radiation cystitis and radiation proctitis. With the increase in availability of chambers across the country, and with increasing number of studies proving the benefits of adjunctive use for various kinds of wounds and other indications, HBOT should be considered in these situations as an essential part of the overall management strategy for the treating surgeon.
Air embolism; compartment syndrome; crush syndrome; decompression sickness; diabetes mellitus; diabetic foot; gas gangrene; hyperbaric medicine; hyperbaric oxygen therapy; hyperbaric; hyperbaric oxygenation; necrotising fasciitis; osteomyelitis; osteoradionecrosis; radiation injuries; radiation necrosis; reperfusion injury; soft tissue infections; surgical flaps; transcutaneous oximetry
Objective: Platelet-rich plasma (PRP) is considered to enhance bone formation especially at early stages of wound
healing, depending on the limited and short life-span of platelets and growth factors. The aim of this study was to
evaluate efficacy of double-application of PRP (DA-PRP) on bone healing in a rabbit calvarial defect model.
Study design: Twenty-eight rabbits, each had two surgically prepared calvarial bone defects (10mm diameter),
were included in this study and randomly divided into six groups. Defects (n=56) were treated with single-application
of PRP (SA-PRP)(n=10), SA-PRP and beta-tricalciumphosphate (SA-PRP+TCP)(n=10), DA-PRP (n=8),
DA-PRP and beta-tricalciumphosphate (DA-PRP+TCP)(n=8), beta-tricalciumphosphate (TCP)(n=10) or left empty
(Control)(n=10). Animals were sacrificed at 30 days postoperatively.
Results: The new bone (NB%) and defect fill (DF%) percentages were calculated from histological slides by
image-analyzer software and statistically analysed. All test groups showed higher NB% than control, but differences
among all groups were insignificant. The TCP treated groups had significantly higher DF% than groups
treated without TCP, however the DF% differences between control, SA-PRP and DA-PRP or TCP, SA-PRP+TCP
or DA-PRP+TCP were insignificant.
Conclusion: Although new bone formation was histomorphologically remarkable at double-application PRP
groups, statistical analyses of the histomorphometric data revealed no significant difference.
Key words: Platelet-Rich Plasma, double application, bone formation, wound healing.
Platelet-derived Growth Factors (GFs) are biologically active peptides that enhance tissue repair mechanisms such as angiogenesis, extracellular matrix remodeling, and cellular effects as stem cells recruitment, chemotaxis, cell proliferation, and differentiation. Platelet-rich plasma (PRP) is used in a variety of clinical applications, based on the premise that higher GF content should promote better healing. Platelet derivatives represent a promising therapeutic modality, offering opportunities for treatment of wounds, ulcers, soft-tissue injuries, and various other applications in cell therapy. PRP can be combined with cell-based therapies such as adipose-derived stem cells, regenerative cell therapy, and transfer factors therapy. This paper describes the biological background of the platelet-derived substances and their potential use in regenerative medicine.
Diabetic foot ulcerations are historically difficult to treat despite advanced
therapeutic modalities. There are numerous modalities described in the literature ranging
from noninvasive topical wound care to more invasive surgical procedures such as
primary closure, skin flaps, and skin grafting. While skin grafting provides faster time to
closure with a single treatment compared to traditional topical wound treatments, the
potential risks of donor site morbidity and poor wound healing unique to the diabetic
state have been cited as a contraindication to its widespread use. In order to garner
clarity on this issue, a literature review was undertaken on the use of split-thickness skin
grafts on diabetic foot ulcers. Search of electronic databases yielded four studies that
reported split-thickness skin grafts as definitive means of closure. In addition, several
other studies employed split-thickness skin grafts as an adjunct to a treatment that was
only partially successful or used to fill in the donor site of another plastic surgery
technique. When used as the primary closure on optimized diabetic foot ulcerations,
split-thickness skin grafts are 78% successful at closing 90% of the wound by eight weeks.
The platelet-rich plasma (PRP) has been advocated as a way to introduce increased concentrations of growth factors and other bioactive molecules to injured tissues in an attempt to optimize the local healing environment. A 94-yr-old woman with various comorbidities presented with a two-week history of severe cutaneous ulcer on the left dorsum of foot. It was caused by recurrent mechanical trauma and did not respond to several wound debridement and simple dressings. However, after she was completed on seven times of autologous PRP treatments, we observed complete healing of the skin lesion within 3 months. Herein, we report a case of recalcitrant cutaneous ulcer with various comorbidities and discuss about the promising possibility of autologous PRP as an effective alternative therapeutic modality.
Platelet Rich Plasma (PRP); Refractory Ulcer; Aged; Diabetes
Platelet-rich plasma (PRP) has been increasingly used in sports medicine applications. Platelets are thought to release growth factors important in wound healing, including transforming growth factor (TGF-β1), platelet-derived growth factor (PDGF-AB), and vascular endothelial growth factor (VEGF). However, little is known about the effect of platelet activator choice on growth factor release kinetics.
The choice of platelet activator would affect the timing and level of growth factor release from PRP.
Controlled laboratory study.
Platelet-rich plasma aliquots were activated with either thrombin or collagen. A control group of whole blood aliquots was clotted with thrombin. Supernatant containing the released growth factors was collected daily for 1 week. Levels of TGF-β1, PDGF-AB, and VEGF were measured using enzyme-linked immunosorbent assay (ELISA).
The use of thrombin as an activator resulted in immediate release of TGF-β1 and PDGF-AB, while the collagen-activated PRP clots released similar amounts each day for 5 days. The use of collagen as an activator resulted in an 80% greater cumulative release of TGF-β1 from the PRP aliquots over 7 days (P < .001). Concentrating platelets to 3 times the systemic blood level resulted in a 3-fold higher release of TGF-β1, 2.5-fold greater release of PDGF, and 5-fold greater release of VEGF (all P < .0001) when compared with whole blood control clots, but no significant differences in the timing of release were noted.
These experiments demonstrated that the choice of platelet activator can significantly influence the release kinetics of cytokines from PRP, with thrombin resulting in an immediate release and collagen having a more sustained release pattern.
The level and rate of growth factor release depends on the selected platelet activator, a factor that should be considered when selecting a PRP system for a given application.
blood clot; growth factor; platelet activation; release kinetics
Wounding following whole-body γ-irradiation (radiation combined injury, RCI) increases mortality. Wounding-induced increases in radiation mortality are triggered by sustained activation of inducible nitric oxide synthase pathways, persistent alteration of cytokine homeostasis, and increased susceptibility to bacterial infection. Among these factors, cytokines along with other biomarkers have been adopted for biodosimetric evaluation and assessment of radiation dose and injury. Therefore, wounding could complicate biodosimetric assessments.
In this report, such confounding effects were addressed. Mice were given 60Co γ-photon radiation followed by skin wounding. Wound trauma exacerbated radiation-induced mortality, body-weight loss, and wound healing. Analyses of DNA damage in bone-marrow cells and peripheral blood mononuclear cells (PBMCs), changes in hematology and cytokine profiles, and fundamental clinical signs were evaluated. Early biomarkers (1 d after RCI) vs. irradiation alone included significant decreases in survivin expression in bone marrow cells, enhanced increases in γ-H2AX formation in Lin+ bone marrow cells, enhanced increases in IL-1β, IL-6, IL-8, and G-CSF concentrations in blood, and concomitant decreases in γ-H2AX formation in PBMCs and decreases in numbers of splenocytes, lymphocytes, and neutrophils. Intermediate biomarkers (7 – 10 d after RCI) included continuously decreased γ-H2AX formation in PBMC and enhanced increases in IL-1β, IL-6, IL-8, and G-CSF concentrations in blood. The clinical signs evaluated after RCI were increased water consumption, decreased body weight, and decreased wound healing rate and survival rate. Late clinical signs (30 d after RCI) included poor survival and wound healing.
Results suggest that confounding factors such as wounding alters ionizing radiation dose assessment and agents inhibiting these responses may prove therapeutic for radiation combined injury and reduce related mortality.
Radiation; Wound; Combined injury; Lymphocyte; Neutrophil; Platelet; Splenocyte; γ-H2AX; Cytokine; DNA damage; Survivin
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.
growth factors; bone regeneration; Platelet-Rich Plasma.
Accidental radioisotope burns are rare. The major components of radiation injury are burns, interstitial pneumonitis, acute bone marrow suppression, acute renal failure and adult respiratory distress syndrome. Radiation burns, though localized in distribution, have systemic effects, and can be extremely difficult to heal, even after multiple surgeries. In a 25 year old male who sustained such trauma by accidental industrial exposure to Iridium192 the early presentation involved recurrent haematemesis, pancytopenia and bone marrow suppression. After three weeks he developed burns in contact areas in the left hand, left side of the chest, abdomen and right inguinal region. All except the inguinal wound healed spontaneously but the former became a non-healing ulcer. Pancytopenia and bone marrow depression followed. He was treated with morphine and NSAIDs, epidural buprinorphine and bupivicaine for pain relief, steroids, antibiotics followed by wound excision and reconstruction with tensor fascia lata(TFL) flap. Patient had breakdown of abdominal scar later and it was excised with 0.5 cm margins up to the underlying muscle and the wound was covered by a latissimis dorsi flap. Further scar break down and recurrent ulcers occurred at different sites including left wrist, left thumb and right heel in the next two years which needed multiple surgical interventions.
Non-healing ulcer; radioisotope burns; reconstructive surgery; unstable scar
Deep and extensive burns of lower extremities present a difficult challenge to healthcare professionals. After debridement, bones, tendons or joints are frequently exposed and cannot be covered by simple autografts. Moreover, in the case of major burns, damage to the surrounding areas of skin and the severity of the patient’s overall condition, often count against using pedicled or microsurgical flaps. In dealing with such complex wounds, which are difficult to treat, several authors have recommended the combined use of Integra® and negative pressure wound therapy (NPWT). They emphasize that NPWT eliminates wound exudate, promotes neovascularisation and cell migration through the Integra® matrix while increasing its stability and adherence to the wound bed, as well as decreasing the time needed for its total integration. The case presented here is of a patient with major third-degree flame burns to the lower extremities. After debridement, the external and internal malleolus bilaterally became exposed as well as the partially debrided tendons (Achilles, extensor digitorum longus, long and short peroneus, anterior and posterior tibialis). After ruling out the use of local or microsurgical flaps due to the patient’s poor general condition and the presence of burns debrided to the fascia over both lower extremities, we elected to manage the patient with a combined treatment using Integra® and NPWT. After three weeks of treatment, the surface layer of the Integra® matrix was replaced with autografts. Due to partial loss of the skin grafts, a second autograft was needed. At present the patient is completely healed; he can walk with full flexion-extension of both ankles.
burns; Integra®; negative pressure wound therapy
Complicated diabetic patients show impaired, delayed wound healing caused by multiple factors. A study on wound healing showed that platelet-rich plasma (PRP) was effective in normal tissue regeneration. Nonetheless, there is no evidence that when plateletrich plasma is applied to diabetic wounds, it normalizes the diabetic wound healing process. In this study, we have analyzed matrix metalloproteinase (MMP)-2, MMP-9 expression to investigate the effect of PRP on diabetic wounds.
Twenty-four-week-old male Otsuka Long-Evans Tokushima Fatty rats were provided by the Tokushima Research Institute. At 50 weeks, wounds were arranged in two sites on the lateral paraspinal areas. Each wound was treated with PRP gel and physiologic saline gauze. To determine the expression of MMP-2, MMP-9, which was chosen as a marker of wound healing, reverse transcription polymerase chain reaction (RT-PCR) was performed and local distribution and expression of MMP-2, MMP-9 was also observed throughout the immunohistochemical staining.
RT-PCR and the immunohistochemical study showed that the levels of MMP-2, MMP-9 mRNA expression in PRP applied tissues were higher than MMP-2, MMP-9 mRNA expression in saline-applied tissues. MMP-9 mRNA expression in wounds of diabetic rats decreased after healing began to occur. But no statistical differences were detected on the basis of body weight or fasting blood glucose levels.
This study could indicate the extracellular matrix-regulating effect observed with PRP. Our results of the acceleration of wound healing events by PRP under hyperglycemic conditions might be a useful clue for future clinical treatment for diabetic wounds.
Platelet-rich plasma; Rats, OLETF; Matrix mtalloproteinase-2; Matrix metalloproteinase-9
Wound healing is a complex biologic process that involves the integration of inflammation, mitosis, angiogenesis, synthesis, and remodeling of the extracellular matrix. However, some wounds fail to heal properly and become chronic. Although some simulated chronic wound models have been established, an efficient approach to treat chronic wounds in animal models has not been determined. The aim of this study was to develop a modified rat model simulating the chronic wounds caused by clinical radiation ulcers and examine the treatment of chronic wounds with adipose-derived stem cells.
Sprague–Dawley rats were irradiated with an electron beam, and wounds were created. The rats received treatment with adipose-derived stem cells (ASCs), and a wound-healing assay was performed. The wound sizes after ASC treatment for 3 weeks were significantly smaller compared with the control condition (p < 0.01). Histological observations of the wound edge and immunoblot analysis of the re-epithelialization region both indicated that the treatment with ASCs was associated with the development of new blood vessels. Cell-tracking experiments showed that ASCs were colocalized with endothelial cell markers in ulcerated tissues.
We established a modified rat model of radiation-induced wounds and demonstrated that ASCs accelerate wound-healing.
Adipose-derived stem cells; Mesenchymal stem cells; Radiation ulcer; Wound model
Autologous platelet-rich plasma has attracted attention in various medical fields recently, including orthopedic, plastic, and dental surgeries and dermatology for its wound healing ability. Further, it has been used clinically in mesotherapy for skin rejuvenation.
In this study, the effects of activated platelet-rich plasma (aPRP) and activated platelet-poor plasma (aPPP) have been investigated on the remodelling of the extracellular matrix, a process that requires activation of dermal fibroblasts, which is essential for rejuvenation of aged skin.
Platelet-rich plasma (PRP) and platelet-poor plasma (PPP) were prepared using a double-spin method and then activated with thrombin and calcium chloride. The proliferative effects of aPRP and aPPP were measured by [3H]thymidine incorporation assay, and their effects on matrix protein synthesis were assessed by quantifying levels of procollagen type I carboxy-terminal peptide (PIP) by enzyme-linked immunosorbent assay (ELISA). The production of collagen and matrix metalloproteinases (MMP) was studied by Western blotting and reverse transcriptase-polymerase chain reaction.
Platelet numbers in PRP increased to 9.4-fold over baseline values. aPRP and aPPP both stimulated cell proliferation, with peak proliferation occurring in cells grown in 5% aPRP. Levels of PIP were highest in cells grown in the presence of 5% aPRP. Additionally, aPRP and aPPP increased the expression of type I collagen, MMP-1 protein, and mRNA in human dermal fibroblasts.
aPRP and aPPP promote tissue remodelling in aged skin and may be used as adjuvant treatment to lasers for skin rejuvenation in cosmetic
Fibroblast; Plasma; Platelet; Rejuvenation
The tenuous blood supply of traditional flaps for wound cover combined with collateral damage by sacrifice of functional muscle, truncal vessels, or nerves has been the bane of reconstructive procedures. The concept of perforator plus flaps employs dual vascular supply to flaps. By safeguarding perforators along with supply from its base, robust flaps can be raised in diverse situations. This is achieved while limiting collateral damage and preserving nerves, vessels, and functioning muscle with better function and aesthesis.
Materials and Methods:
The perforator plus concept was applied in seven different clinical situations. Functional muscle and fasciocutaneous flaps were employed in five and adipofascial flaps in two cases, primarily involving lower extremity defects and back. Adipofascial perforator plus flaps were employed to provide cover for tibial fracture in one patients and chronic venous ulcer in another.
All flaps survived without any loss and provided long-term stable cover, both over soft tissue and bone. Functional preservation was achieved in all cases where muscle flaps were employed with no clinical evidence of loss of power. There was no sensory loss or significant oedema in or distal to the flap in both cases where neurovascular continuity was preserved during flap elevation. Fracture union and consolidation were satisfactory. One patient had minimal graft loss over fascia which required application of stored grafts with subsequent take. No patient required re-operation.
Perforator plus concept is holistic and applicable to most flap types in varied situations. It permits the exercise of many locoregional flap options while limiting collateral functional damage. Aesthetic considerations are also addressed while raising adipofascial flaps because of no appreciable donor defects. With quick operating times and low failure risk, these flaps can be a better substitute to traditional flaps and at times even free tissue transfers.
Function and form preservation; perforator plus flaps