Application of platelet-rich plasma accelerates the wound healing process in acute and chronic ulcers through rapid migration and upregulation of cyclin A and CDK4 in HaCaT cells

The Effects of Tissue Healing Factors in Wound Repair Involving Absorbable Meshes: A Narrative Review

Wound healing is a complex and meticulously orchestrated process involving multiple phases and cellular interactions. This narrative review explores the intricate mechanisms behind wound healing, emphasizing the significance of cellular processes and molecular factors. The phases of wound healing are discussed, focusing on the roles of immune cells, growth factors, and extracellular matrix components. Cellular shape alterations driven by cytoskeletal modulation and the influence of the 'Formin' protein family are highlighted for their impact on wound healing processes. This review delves into the use of absorbable meshes in wound repair, discussing their categories and applications in different surgical scenarios. Interleukins (IL-2 and IL-6), CD31, CD34, platelet rich plasma (PRP), and adipose tissue-derived mesenchymal stem cells (ADSCs) are discussed in their respective roles in wound healing. The interactions between these factors and their potential synergies with absorbable meshes are explored, shedding light on how these combinations might enhance the healing process. Recent advances and challenges in the field are also presented, including insights into mesh integration, biocompatibility, infection prevention, and postoperative complications. This review underscores the importance of patient-specific factors and surgical techniques in optimizing mesh placement and healing outcomes. As wound healing remains a dynamic field, this narrative review provides a comprehensive overview of the current understanding and potential avenues for future research and clinical applications.

Research trends on platelet-rich plasma in the treatment of wounds during 2002-2021: A 20-year bibliometric analysis

Platelet-rich plasma (PRP) has attracted attention because of its potential to accelerate the wound healing process. However, resources for evaluating research trends in the treatment of wounds with PRP were limited. In this study, we aimed to make a bibliometric analysis of the literature related to PRP in the treatment of wounds and explore the research status, hotspots and frontiers in this field in recent 20 years. Studies about PRP treatment for wounds from 2002 to 2021 were retrieved from the Science Citation Index Expanded (SCI-E) of Web of Science (WOS) database. Visualisation softwares such as VOSviewer and SCImago Graphica, and CiteSpace were used to analyse the research trends and features. A total of 1748 studies were identified in the SCI-Expanded from 2002 to 2021. The number of publications on PRP in the treatment of wounds has shown an increasing trend, from 6 (in 2002) to 228 (in 2021). The papers published in the United States have led in times cited (14637) and H-index (63). Though Italy was slightly lower than China in the number of publications, the H-index and average cited (47, 28.45) were higher than that of China (38, 27.01). The strongest keyword was "fibrin" (strength = 13.07), and the longest burst duration keyword was "thrombin" (began in 2002 and ended in 2014). The largest 10 co-citation clusters are as follows: endothelial cell proliferation (#0), regenerative medicine-associated treatment (#1), diabetic wound healing (#2), autologous derived (#3), platelet-rich fibrin (#4), tissue engineering (#5), regenerative potential (#6), clinical randomised trial (#7), histologic observation (#8), and wound bacteria (#9). The United States has made the most outstanding contribution in this field. Chinese researchers need to enhance the quality of publications further. Wound Repair Regen. is the most noteworthy journal. The mechanism of growth factors of PRP, combination therapy, preparation of PRP, and related clinical trials may be topics that need attention.

Astragaloside IV promotes keratinocyte proliferation and migration through upregulating lncRNA H19 recruited ILF3 to enhance the stability of CDK4 mRNA

Skin is the first line of the body to resist pathogen invasion. A potentially fatal infection may result from problems with wound healing. Small molecule drugs like astragaloside IV (AS-IV) show pro-healing activities, but the mechanisms are not fully understood. Using real-time quantitative PCR and a western blot assay, the amount of gene expression was evaluated. The proliferation and migration of keratinocytes were determined by MTS and wound healing assay, respectively. The binding of lncRNA H19 to RBP protein ILF3 and the binding of ILF3 protein to CDK4 mRNA were confirmed by RNA immunoprecipitation. Treatment with AS-IV enhanced the expression of lncRNA H19, ILF3, and CDK4 and improved the proliferation and migration of keratinocytes HaCaT. Additionally, apoptosis of keratinocytes was attenuated by AS-IV. Further studies showed that both lncRNA H19 and ILF3 were important for AS-IV-mediated keratinocyte growth and migration. In addition, lncRNA H19 recruited ILF3 to increase CDK4 mRNA level and enhanced cell proliferation. We discovered a lncRNA H19/ILF3/CDK4 axis that is activated by AS-IV to promote keratinocyte migration and proliferation. These results elucidate the mechanism of action of AS-IV and justify its application in further application in wound healing treatment.

Use of Autologous Platelet Rich Plasma (A-PRP) for Postpartum Perineal Repair Failure: A Case Report

Perineal wound dehiscence is an uncommon but important postpartum complication. In many cases, it leads to extreme pain and urinary and defecation problems. For up to several weeks, it can interfere with the mother’s daily activity, affecting psychosexual health and body image. The best way to manage perineal wound breakdown (resuturing vs. spontaneous closure) after childbirth remains controversial. A-PRP is the autologous human plasma containing an increased platelet concentration, rich in growth factors, and mediators with hemostatic, anti-inflammatory, and antimicrobial properties. It accelerates the natural healing process. Even though A-PRP is widely used in orthopedics and dermatology, its use in gynecological injuries is limited. We describe here a case of a woman with postpartum perineal dehiscence treated with A-PRP with positive outcomes.

Platelet-derived concentrates influence human keratinocyte proliferation in vitro and induce wound healing in a prospective case series of chronic wounds of different entities in vivo

Objectives

Soft tissues defects can extend into the fat layer or even deeper and can cause significant clinical disadvantages like pain, infections, and loss of function. In particular, chronic wounds are difficult to treat, as split-thickness skin grafts (STSGs) have varying success rates. To improve wound healing in chronic wounds, the authors have studied the application of platelet-mediator concentrate (PMC) in a human keratinocyte culture model in vitro and of autologous platelet concentrates (PRP) in a combination with surgical procedures in vivo as second line therapy in patients with initially failed wound closure.

Methods

For in vitro testing on keratinocytes, a PMC was processed with a commercially available bedside system (ATR^®, Curasan, Germany). In a clinical, nonrandomized study, five in-house patients with chronic wounds were treated using a combination of surgical debridement and autologous PRP. Time of healing as determined by epithelization as well as laser Doppler imaging to visualize blood flow was analyzed. Additionally, changes in ease of surgical wound closure were determined. Finally, the quality of life of patients was assessed using a validated questionnaire (clinicaltrials.gov # NCT03667638).

Results

In vitro testing shows a significant effect of PMC on keratinocyte proliferation in cell culture. Clinical studies showed that patients treated with PRP had initiation of wound closure, higher blood flow after PRP injection, and easier wound closure as well as improved quality of life.

Conclusions

The injection of platelet concentrates to treat chronic wound defects presents a favorable addition to treatment where single surgical procedures have failed and may improve current therapy options.

PRP Versus Standard of Care for Venous leg Ulcers: A Systematic Review and Meta-Analysis of Prospective Comparative Studies

Venous leg ulcers (VLUs) are chronic and recalcitrant lower limb wounds that affect millions of patients annually, severely reducing their quality of life, and causing a significant burden on the health care system. Recently, Platelet rich plasma (PRP) has been used to improve healing of VLUs. This systematic review aimed at evaluating the effectiveness of PRP versus the standard of care commonly used to treat VLUs. Ten prospective studies (8 randomized) met the inclusion criteria comprising 451 patients with 527 VLUs. Results were as follows: a) the weighted Odds Ratio (OR) of the mean healing rate was 2.84 (95% CI = 1.160 to 5.056, I2 = 41.4%, p = 0.0004), b) the mean healed ulcer areas were 79.2 ± 19% for the PRP group and 51.7 ± 36% for the control group (p = 0.007) in favor of the PRP group, and c) the weighted infection OR showed no significant difference between both groups. Additionally, negative correlations were found between healing rate and duration of VLUs and initial size of the ulcers. This meta-analysis demonstrated significant beneficial effects of PRP versus standard of care on healing rate, reduction in surface, and reduction in healing time of VLUs. Infection and other complications were similar to standard of care. Therefore, our analytical data would support the use of PRP as a safe and effective treatment for VLUs.

Recombinant Prolidase Activates EGFR-Dependent Cell Growth in an Experimental Model of Inflammation in HaCaT Keratinocytes. Implication for Wound Healing

This study was conducted to investigate the proliferative capacity of recombinant human prolidase (rhPEPD) in a human model of inflammation induced by IL-1β in HaCaT keratinocytes. In this report, we provide evidence that IL-1β stimulates keratinocyte proliferation, and rhPEPD significantly augmented this process through activation of epidermal growth factor receptor (EGFR) and downstream signaling proteins as phosphorylated Akt, ERK1/2, and STAT3, which are implicated in keratinocyte migration, proliferation, and epithelialization during the wound healing process. Inhibition of PEPD-dependent EGFR signaling by gefitinib supported the finding. Moreover, during activation of EGFR in the presence of IL-1β the epithelial-to-mesenchymal transition (EMT) occurred via downregulation of E-cadherin and upregulation of N-cadherin. The phenomenon was accompanied by an increase in the activity of matrix metalloproteinase-9 (MMP-9), suggesting extracellular matrix (ECM) remodeling during the inflammatory process. MMP-9 activation may result from nuclear translocation of NF-κB through IKK-mediated IκBα degradation. Interestingly, some mutated variants of PEPD (rhPEPD-G448R, rhPEPD-231delY, and rhPEPD-E412K) evoked the ability to induce EGFR-dependent HaCaT cell proliferation. To the best of our knowledge, this is the first report on the cross-talk between PEPD and IL-1β in the process of keratinocyte proliferation. The data suggest that both enzymatically active and inactive rhPEPD may activate EGFR-dependent cell growth in an experimental model of inflammation in HaCaT keratinocytes and the knowledge may be useful for further approaches for therapy of wound healing disorders.

Novel therapeutic targets for diabetes-related wounds or ulcers: an update on preclinical and clinical research

INTRODUCTION

Diabetes-related wounds, particularly diabetes-related foot ulcers, are mainly caused by lack of foot sensation and high plantar tissue stress secondary to peripheral neuropathy, ischemia secondary to peripheral artery disease, and dysfunctional wound healing. Current management of diabetes-related wounds involves the offloading of high foot pressures and the treatment of ischemia through revascularization. Despite these treatments, the global burden of diabetes-related wounds is growing, and thus, novel therapies are needed. The normal wound healing process is a coordinated remodeling process orchestrated by fibroblasts, endothelial cells, phagocytes, and platelets, controlled by an array of growth factors. In diabetes-related wounds, these coordinated processes are dysfunctional. The past animal model and human research suggest that prolonged wound inflammation, failure to adequately correct ischemia, and impaired wound maturation are key therapeutic targets to improve diabetes-related wound healing.

AREAS COVERED

This review summarizes recent preclinical and clinical research on novel diabetes-related wound treatments. Animal models of diabetes-related wounds and recent studies testing novel therapeutic agents in these models are described. Findings from clinical trials are also discussed. Finally, challenges to identifying and implementing novel therapies are described.

EXPERT OPINION

Given the growing volume of promising drug therapies currently under investigation, it is expected within the next decade, that diabetes-related wound treatment will be transformed.

Platelet lysate converts M (IFNγ+LPS) macrophages in CD206+ TGF-β+ arginase+ M2-like macrophages that affect fibroblast activity and T lymphocyte migration

Macrophages, thanks to their extreme plasticity, exert critical roles in wound healing by orchestrating tissue defenses in the early inflammatory phase, and by promoting tissue regeneration and angiogenesis at a later time point. In parallel, platelets release a large number of preformed molecules that could affect immunocyte functions. Platelet-rich plasma and platelet lysate (PL) have been widely used as a therapeutic preside for ulcers, although little is known about the effects of platelet-derived biomolecules on macrophage functions during wound healing. In this study, we analyze the effects of PL on macrophages phenotype and functions. Monocyte-derived macrophages were cultured in the presence of interferon-γ and lipopolysaccharides to induce the M1 polarization and were further exposed to 10% PL. PL treatment reduced CD80, CD86, and PDL-1 and enhanced CD206 and CD200R expression on macrophages analyzed by cytofluorimetry. Additionally, macrophage cultures show reduced TNF-α and CXCL10, while increased arginase protein, PPAR, TGF-β, and VEGF. TGF-β secretion was paralleled by the decrease of NFkB and increase of STAT3, STAT6, and SMAD2 and SMAD4. Supernatants of PL-treated macrophages induced a significant increase of type-I collagen and to a lesser extent of type-III collagen production by fibroblasts. Finally, the supernatant of PL-treated macrophages showed significantly reduced capacity to induce the in vitro migration of T lymphocytes. Our results demonstrate that PL dampens the macrophage secretion of pro-inflammatory cytokines and induces the release of arginase, TGF-β, and VEGF that may affect angiogenesis and tissue regeneration, thus facilitating the wound healing process.

Eliminating non-healing wounds: a review

Non-healing cutaneous wounds, including pressure, diabetic and venous ulcers, are wounds where the skin and underlying tissues die due to ischemia, infection, metabolic conditions, immunosuppression or radiation. Some can be eliminated with relatively straightforward techniques, although they may continue to grow in diameter and depth, becoming increasingly painful and never heal. Others respond more slowly or poorly to treatment, while others are recalcitrant to treatments. This review examines the etiology of non-healing wounds and different wound management treatments. In addition, it examines the efficacy of platelet-rich plasma in promoting wound healing and its potential mechanisms of action. It is concluded that platelet-rich plasma alone, but more effectively when combined with another technique(s), has the greatest potential for promoting complete wound healing. However, further studies are required to determine whether the efficacy of wound healing induced by each of these techniques is enhanced by applying the techniques simultaneously.

Cost and effectiveness of Platelet Rich Plasma in the healing of varicose ulcer: Meta-analysis

OBJECTIVES

to analyze the evidence on the cost and effectiveness of Plaque Rich Plasma in the treatment of venous ulcers compared to other topical therapies.

METHODS

systematic review, with search in the databases: COCHRANE, EMBASE, MEDLINE via PubMed, LILACS, CINAHL, SCOPUS, without temporal cut and in the English, Portuguese and Spanish languages.

RESULTS

fifteen articles were included, a cost-minimization analysis showed that the cost of Plaque Rich Plasma is € 163.00 ± 65.90, slightly higher than the cost of standard dressing. Regarding effectiveness, the results of the studies associated with the meta-analysis suggest a tendency that Plaque Rich Plasma is effective in the healing of venous ulcers.

CONCLUSIONS

it is concluded that there are few studies about the cost of Platelet Rich Plasma and this product tends to be effective in the healing of venous ulcers. However, more controlled and randomized clinical studies are necessary in order to establish a stronger recommendation.

Platelet-Rich Plasma Promotes the Proliferation of Human Keratinocytes via a Progression of the Cell Cycle. A Role of Prolidase

Although the role of platelet-rich plasma (PRP) in tissue regeneration has been confirmed in many studies, the mechanism of this process is still not fully understood. Human keratinocytes (HaCaT) cells were used as an experimental model for studies on the effects of PRP on cell proliferation, migration, collagen biosynthesis, prolidase activity, and its expression and anabolic signaling. The activation of epidermal growth factor receptor (EGFR), β₁-integrin, and insulin-like growth factor-1 receptor (IGF-1R) by PRP were investigated by western blot and immunocytochemistry. It has been found that PRP induced keratinocytes migration and proliferation through activation of cell cycle progression and EGFR downstream signaling. Similar biological effects were achieved by an addition to the culture medium of prolidase (PEPD), a ligand of EGFR (PRP is a rich source of PEPD–2 ng/mL). PRP-dependent stimulation of collagen biosynthesis was accompanied by an increase in the expression of NF-κβ, IGF-1R-downstream signaling proteins, and PEPD activity. The data suggest that PRP activates a complex of growth factors and adhesion receptors that stimulate cell proliferation, migration, and collagen biosynthesis. PRP induces PEPD-dependent human keratinocyte proliferation through activation of the EGFR receptor. Our study provides a novel mechanism of PRP-dependent wound healing.

Exosomes from adipose-derived stem cells and application to skin wound healing

Skin wound healing is an intractable problem that represents an urgent clinical need. To solve this problem, a large number of studies have focused on the use of exosomes (EXOs) derived from adipose‐derived stem cells (ADSCs). This review describes the mechanisms whereby ADSCs‐EXOs regulate wound healing and their clinical application. In the wound, ADSCs‐EXOs modulate immune responses and inflammation. They also promote angiogenesis, accelerate proliferation and re‐epithelization of skin cells, and regulate collagen remodelling which inhibits scar hyperplasia. Compared with ADSCs therapeutics, ADSCs‐EXOs have highly stability and are easily stored. Additionally, they are not rejected by the immune system and have a homing effect and their dosage can be easily controlled. ADSCs‐EXOs can improve fat grafting and promote wound healing in patients with diabetes mellitus. They can also act as a carrier and combined scaffold for treatment, leading to scarless cutaneous repair. Overall, ADSCs‐EXOs have the potential to be used in the clinic to promote wound healing.

The Anti-photoaging Effects of Pre- and Post-treatment of Platelet-rich Plasma on UVB-damaged HaCaT Keratinocytes

Platelet-rich plasma (PRP) has seen wide clinical use owing to its regenerative and repair abilities.

OBJECTIVE

To investigate the anti-photoaging effects of pre- and post-treatment of PRP on UVB-damaged HaCaT cells.

METHODS

HaCaT cells were irradiated with 80 mJ/cm² UVB, before or after PRP treatment (1000 × 10⁷ /L), and following measurements were taken: survival rate of UVB-irradiated HaCaT cells, malondialdehyde (MDA) content and activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT). Western blot was used to determine the effect of different PRP intervention on the expression of PI3K, AKT, ERK, MMP-1, MMP-9, TIMP-1 and γ-H2AX in the UVB-irradiated HaCaT cells.

RESULTS

pre- and post-PRP treatment reduced MDA content and increased the activities of GSH-Px, SOD and CAT in photoaged HaCaT cells. These changes resulted in reduced cytotoxic effects. Besides, different PRP intervention promoted cell proliferation via PI3K/AKT pathway. Furthermore, PRP application suppressed the expression of γ-H2AX. Also, PRP intervention alleviated photoaging effects by upregulating the expression level of tissue inhibitor of metalloproteinases-1 (TIMP-1) while downregulating matrix metalloproteinase (MMP) expression level in photoaged HaCaT cells.

CONCLUSION

pre- and post-PRP treatment play anti-photoaging role through strengthening cellular oxidative defense capacity, mitigating MMP expression, alleviating DNA damages and promoting proliferation of UVB-irradiated HaCaT cells.

Platelet-Rich Plasma: The Journey so Far !

Platelet-rich plasma (PRP) is an autologous blood product, obtained after blood centrifugation. PRP is rich in growth factors which promote tissue-healing, alter angiogenesis, and possess versatile immunomodulatory effects, in the relative absence of any significant demonstrable adverse effects. Consequently, PRP has found application in multiple specialities in recent years, including dermatology. A literature search was performed on PubMed, Medline database, and Google Scholar, using keywords like platelet-rich plasma (PRP), platelet-concentrated plasma, platelet-rich growth factors, autologous platelet concentrate. Relevant studies were selected, and data was analyzed following extraction. Studies show that PRP has not only been used as an adjunctive modality but has been employed as a stand-alone therapy as well. Multiple authors have reported PRP to be efficacious in disparate dermatological conditions, like alopecia, skin rejuvenation, healing of refractory cutaneous ulcers, and even acne scar management. The strongest evidence so far has been demonstrated in androgenetic alopecia and facial skin rejuvenation. However, routine use in dermatological conditions is hampered by the relative paucity of high-quality evidence and large randomized studies. Furthermore, PRP composition and preparation methods are not yet standardized and even the treatment regimens proposed too vary widely. The present review provides a bird's eye view of the evidence available so far regarding the use of PRP in dermatology. The review focusses more on recent prospective studies, including randomized trials and tries to summarize the evidence in a brief, but comprehensive manner.

Challenges and New Therapeutic Approaches in the Management of Chronic Wounds

Chronic non-healing wounds are estimated to cost the US healthcare $28-$31 billion per year. Diabetic ulcers, arterial and venous ulcers, and pressure ulcers are some of the most common types of chronic wounds. The burden of chronic wounds continues to rise due to the current epidemic of obesity and diabetes and the increase in elderly adults in the population who are more vulnerable to chronic wounds than younger individuals. This patient population is also highly vulnerable to debilitating infections caused by opportunistic and multi-drug resistant pathogens. Reduced microcirculation, decreased availability of cytokines and growth factors that promote wound closure and healing, and infections by multi-drug resistant and biofilm forming microbes are some of the critical factors that contribute to the development of chronic non-healing wounds. This review discusses novel approaches to understand chronic wound pathology and methods to improve chronic wound care, particularly when chronic wounds are infected by multi-drug resistant, biofilm forming microbes.

Inhibitory Effect of Hydroxysafflor Yellow B on the Proliferation of Human Breast Cancer MCF-7 Cells

BACKGROUND

A recent patent has been issued for hydroxysafflor yellow A (HSYA) as a drug to prevent blood circulation disorders. Hydroxysafflor yellow B (HSYB), an isomer of HSYA with antioxidative effects, has been isolated from the florets of Carthamus tinctorius. The effects of HSYB on the proliferation of cancer cells and its mechanism of action have not been investigated.

OBJECTIVE

The aims of this study were to investigate the anti-cancer effects and the molecular mechanism of HSYB for breast cancer MCF-7 cells.

METHODS

MTT assays and colony formation assays were used to assess the survival and proliferation of MCF-7 cells, respectively. Hoechst 33258 and flow cytometry were used to measure cell apoptosis and flow cytometry to determine effects on the cell cycle. Western blots were used to measure protein levels.

RESULTS

Treatment with HSYB reduced survival and proliferation of human breast cancer MCF-7 cells in a dose-dependent manner. Furthermore, HSYB arrested the MCF-7 cell cycle at the S phase and downregulated cyclin D1, cyclin E, and CDK2. Compared with a control group, HSYB suppressed the protein levels of p-PI3K, PI3K, AKT, and p-AKT in MCF-7 cells. In addition, HSYB decreased the levels of Bcl- 2, increased the levels of Bax, cleaved caspase-3 and caspase-9, and subsequently induced MCF-7 cell apoptosis.

CONCLUSION

These data demonstrate that HSYB arrests the MCF-7 cell cycle at the S phase and induces cell apoptosis. Patent US20170246228 indicates that HSYB can be potentially used for the prevention and treatment of human breast cancer.

A Meta-analysis of the Evidence for Assisted Therapy with Platelet-Rich Plasma for Atrophic Acne Scars

BACKGROUND

A number of studies have investigated the role of platelet-rich plasma (PRP) as an assisted therapy for atrophic acne scars. However, the results are diverse, and no up-to-date meta-analysis was found that exclusively examined atrophic acne scar treatment.

OBJECTIVES

To perform a meta-analysis to assess improvements in the side effects of PRP and the effect of assisted therapy for atrophic acne scars.

METHODS

This study followed PRISMA guidelines. A comprehensive search of the literature was carried out in September 2018 using the electronic databases of PubMed, EMBASE, MEDLINE, and the Cochrane Library.

RESULTS

Seven articles were included in this review. All of the studies published utilized PRP as additive therapy. The major therapies included fractional carbon laser therapy and microneedling. Five studies (249 participants) reported four degrees of improvement on an improvement scale (degrees 3 and 4 were considered improvement in this analysis). Four studies (200 participants) reported mean improvement scores. A significantly higher degree of improvement was shown in the PRP group compared to the control group (OR = 8.19; 95% CI 4.32-15.52; p < 0.00001), as well as better mean improvement score (WMD = 23.73; 95% CI 18.60-28.87; p < 0.00001). Substantial heterogeneity was seen in the degree of improvement (I² = 54% p = 0.07) and the mean improvement score (I² = 75%; p = 0.008). There were overall fewer monitored side effects, including erythema and edema (in days), in the PRP groups; however, no significance was found.

CONCLUSIONS

This review shows that PRP is a useful assisted therapy for atrophic acne scars, which can achieve better improvement.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Prospective application of exosomes derived from adipose-derived stem cells in skin wound healing: A review

BACKGROUND

Wound healing has always been an intractable medical problem for both clinicians and researchers and a burden for patients both physically and financially. Poor wound healing at the injury site, especially in an exposed site, is associated with an unappealing esthetic appearance in patients and also results in a bad skin barrier, tissue infection and necrosis, loss of main function in extreme cases and other serious local and systemic consequences. There is a crucial and urgent need for newer, more efficacious methods for enhancing the healing process to achieve optimal outcomes morphologically and functionally. Recent advances have focused on developing therapies that promote tissue regeneration through positively activating the mechanism of tissue repair. Given the increasing high-quality studies concerning exosomes derived from adipose-derived stem cells (ADSCs-Exos), their potential use in accelerating or supporting the wound healing process has gained increasing attention in recent years.

AIMS

In this review, we present an overview of the recent advances in the field of ADSCs-Exos and investigate their benefit in wound healing for skin regeneration with the expectation of providing a perspective on how to best utilize this powerful cell-free therapy in the future.

METHODS

A retrospective review of the published data was conducted.

RESULTS

Most studies have shown the possible roles of ASCs-derived exosomes (ADSCs-Exos) in cutaneous wound healing through regulation of the inflammatory response and promotion of cell proliferation, migration, differentiation, angiogenesis and matrix reconstruction to provide a new perspective strategy for the use of ASCs-Exos in skin wound healing.

CONCLUSION

ADSCs-Exos are likely to achieve the best functionally and cosmetic skin wound healing while avoiding undesirable consequences. ADSCs-Exos represent a novel therapeutic tool in soft tissue repair; however, further randomized, double-blind, comparative clinical trials must be performed to determine the specific mechanisms, safety and other relevant cosmetic concerns.

Effects of topical application of platelet-rich plasma on esophageal stricture and oxidative stress after caustic burn in rats: Is autologous treatment possible?

BACKGROUND

Caustic esophageal burn is still an important health problem in pediatric surgery. Although there are a number of experimental and clinical studies to increase the recovery of the esophagus and reduce the stenosis rate, there is no consensus on the treatment protocol. Platelet-rich plasma (PRP) is an autologous blood product, which has positive effects on wound healing, reepithelization and scar prevention. The aim of our study was to investigate the effects of PRP on stricture formation and oxidative status after caustic esophageal injury in rats.

METHODS

Twenty-one rats were divided into three groups [Sham operation (n = 8), corrosive esophageal burn with 30% NaOH (n = 6), topical PRP application after corrosive burn (n = 7)]. On the postoperative 21st day, oxidative markers were measured in the serum, and collagen accumulation and stenosis index were measured histopathologically to assess the efficacy of PRP treatment.

RESULTS

Postoperative weight was higher than preoperative weight in Sham and PRP groups, but lower in the Burn group (p < 0.05). No difference was observed between Sham and PRP groups at total antioxidant status and paraoxonase values, but a significant decrease was found in the Burn group. Group PRP had higher total oxidant status and arylesterase levels than Group Burn (p < 0.05). There was no difference in total thiol values between PRP and Sham group. Histopathological scoring for muscularis mucosa damage revealed a significant reduction in Group PRP, compared to Group Burn (p < 0.05). Esophageal wall thickness and SI were reduced, and luminal diameter was increased in Group PRP compared to Group Burn (p < 0.05).

CONCLUSION

For the first time in the literature, these results indicate that topical PRP treatment after the experimental corrosive burn has a positive effect on oxidative stress, mucosal healing and decreased stricture development. PRP may be an alternative at the clinical treatment because it can be used during diagnostic esophagoscopy.

TYPE OF STUDY

Treatment study Level I (randomized controlled trial).

A mini-pig model for evaluating the efficacy of autologous platelet patches on induced acute full thickness wound healing

Background

Autologous platelet concentrates are currently widely used across different areas of regenerative medicine in order to enhance the wound healing process. Although several protocols for platelet concentrates are available, their application remains difficult due to different protocols leading to distinct products with vary potential biological uses. In this study, we attempted to make a platelet patch (PP) using mixtures of platelet rich plasma (PRP) injection and platelet rich fibrin (PRF) to promote wound repair and regeneration.

Results

Experiments were performed using a full-thickness wound model in mini-pigs. Autologous PRP, PRF and PP were prepared immediately before creating four full-thickness skin wounds in pigs. We quantified concentrations of platelets, thrombin and various growth factors to ensure that the desired effect can be produced. After surgery, hydrocolloid dressing, PRP injection, PRF and PP was applied to experimentally induced wounds. Application efficacy was evaluated by measurement of wound sizes and histological examination. The results indicated that all wounds showed a significant size reduction. Wound repair efficacy in response to PP treatment exhibited enhanced re-epithelialization compared to PRP and PRF (P < 0.05) and higher wound contraction than did PRF application (P < 0.05). Another aspect, experiment using DsRed transgenic pigs as blood donors demonstrated that leucocytes in PP were incorporated into the wound bed at the end of the study, suggesting that leucocytes activity is stimulated in response to PP application. Safety of the experimental processes was also confirmed by examination of organ biopsies.

Conclusions

We used a mini-pig model to evaluate the efficacy of lab-made PP on induced full-thickness wound healing. Results demonstrated that application of one piece of PP was enough to obtain comparable efficacy versus general utilization of PRP or PRF for wound care. We also demonstrated that leucocytes in PP were incorporated into the wound bed and no safety concerns have been found in the whole experiment. This study provides a novel and feasible method for veterinary or clinical wound care.

Autologous platelet-rich plasma for healing chronic venous leg ulcers: Clinical efficacy and potential mechanisms

The overall quality of evidence of autologous platelet-rich plasma (PRP) for treating chronic wounds remains low. While further well-designed clinical studies are clearly required to convincingly demonstrate the efficacy of autologous PRP in improved healing of venous leg ulcers (VLUs) and other chronic wounds, there is also an increasing need to better define the underlying mechanisms of action and whether positive outcomes can be predicted based on the analysis of PRP. This brief review will discuss the current understanding of autologous PRP in VLUs and whether molecular evaluation of PRP at the time of collection could potentially be informative to clinical outcomes. Benefits of the autologous PRP treatment strategy include that PRP is easily accessible and is relatively inexpensive and safe. Better understanding of the mechanisms involved could improve treatment, enable supplementation, and/or lead to gains in product development. Analysis of PRP could also add value to future clinical trials on efficacy and potentially personalised treatment regimens.

Effectiveness of Autologous Platelet-Rich Plasma for the Healing of Ulcers after Endoscopic Submucosal Dissection

Background/Aims

Platelet-rich plasma (PRP) has been used for wound healing in various medical fields. The aim of this study was to evaluate the clinical efficacy and safety of local PRP injections after endoscopic submucosal dissection (ESD).

Methods

Patients were non-randomly divided into the following two groups: (1) control group in which patients were administered only an intravenous proton pump inhibitor (PPI), and (2) a study group in which patients were administered an intravenous PPI and a topical PRP injection. We assessed the reduction in the ulcer area and stage of the ulcer after the procedure (24 hours, 48 hours, and 28 days after endoscopic surgery).

Results

We enrolled 7 study and 7 control patients. In the study group, the rate of ulcer reduction was 59% compared to 52% in the control group (p=0.372), 28 days after ESD. There were 5 patients in the S stage and 2 patients in the H stage in the study group compared to no patient in the S stage and 7 patients in the H stage in the control group (p=0.05), 28 days after ESD. There were no serious complications in either group.

Conclusions

The local injection of PRP is a safe and effective procedure for ulcer healing after ESD.

Use of platelet-rich plasma to facilitate wound healing

Platelet-rich plasma (PRP) is widely used nowadays in different fields of medicine, affecting physiological processes including tissue regeneration. The use of PRP in maxillofacial surgical interventions and its efficiency in the improvement of postoperative wound healing were analysed. Patients undergoing plastic and reconstructive surgeries in the maxillofacial region were recruited: 50 patients were enrolled into a control group (received no PPRP injection) and 50 patients were enrolled into a treatment group, where PRP was applied during the surgical procedure. Evaluation of treatment outcomes was carried out by determination of IL-1β, TNFα, and IL-6 cytokines levels in the wound-drain fluid. The stages of wound healing were assessed by cytological analyses and ultrasound within a month period. The use of the PRP has substantially positive effects, contributing to the improvement of the healing process. In the treatment group, fibroblasts, macrophages, and collagen fibres appeared and their quantities increased earlier than when compared with control group patients. The concentration of IL-1β and TNFα in wound fluid on day 1 and day 5 after operation was higher for the treatment group as opposed to the control group, which was linked to the influence of PRP on inflammatory and granulation phases of the healing process. An ultrasound examination showed less oedema and infiltration in the tissues around the wound of the treatment group.

[New progress in the treatment of chronic wound of diabetic foot]

Diabetic foot is one of the serious complications of diabetic patients. It is caused by diabetes combined with different degrees of lower extremity vascular lesions and neuropathy, and the wound can not heal for a long time. The serious results can cause bone marrow infection, bone destruction, and have high disability and death rate. At present, there are various treatment methods for diabetic foot chronic wound. On the basis of internal medicine controlling blood sugar, anti infection, lowering blood lipid, improving microcirculation and nourishment nerve, the surgical method is adopted, including the debridement of the necrosis in a short time to prevent the infection from spreading; maggot biological debridement and ozone chemical debridement will promote the growth of granulation tissue while controlling infection. Skin grafting, skin flap transplantation, skin distraction closure can be used to repair soft tissue defects, or fat transplantation, platelet-rich plasma, and rich blood are used for the refractory wound after infection control. In patients with diabetic foot, the reconstruction of lower limb blood supply is beneficial to the recovery of chronic ischemic wounds. It is feasible to improve the blood supply of the lower extremities, improve the blood supply of the lower extremity artery bypass grafting, and improve the microcirculation of the peripheral vessels around the lower extremities. Lower extremity vascular bypass pressure perfusion therapy for vascular network expansion, tibia lateral moving technique for lower limb microcirculation reconstruction. For diabetic foot ulcer caused by peripheral neuropathy, such as Charcot foot, while the application of external fixator, total contact cast technology of affected foot for reducing treatment to promote wound healing; the preparation of orthopedic shoes can play a maximum protective effect on the healing of diabetic foot wound healing.

A bioartificial dermal regeneration template promotes skin cell proliferation in vitro and enhances large skin wound healing in vivo

A novel bioartificial dermal regeneration template has been developed using platelet-rich plasma and acellular animal skin collagen sponge for the treatment of larger area and full thickness skin wounds. This platelet-rich plasma-collagen sponge keeps native skin structure and contains huge amounts of growth factors. The effect of this bioartificial dermal regeneration template was tested in vitro and in vivo via a mimic poor wound healing process by adding collagenase I into cell culture medium or the wound area. The in vitro experimental results indicated that the rat skin cells grew faster and produced more collagen in platelet-rich plasma-collagen sponge with collagenase than those treated either with collagen sponge plus collagenase, or collagenase, or control group without treatment. The in vivo experiments were performed by large rat skin wounds, 1.5 cm diameter, treated either with collagenase, or collagenase plus collagen sponge, or collagenase plus platelet-rich plasma-collagen sponge. The wound without treatment was used as a control. The wounds treated with collagenase-containing platelet-rich plasma-collagen sponge healed 4 times faster than the untreated wounds, 6 times faster than the collagenase treated wounds, 2.4 times faster than collagenase-containing collagen sponge treated wounds. The immunostaining indicated that the healed tissues in the wound areas treated with collagenase-containing platelet-rich plasma-collagen sponge were composed of collagen type I and collagen III with blood vessels and hair follicles. The results demonstrated that this collagenase-containing platelet-rich plasma-collagen sponge works as a bioartificial dermal regeneration template. The application of this collagenase-containing platelet-rich plasma-collagen sponge promotes the traumatic skin wound healing and permits the reconstitution of the inherent barrier functions of the skin.

Autologous platelet-rich plasma versus conventional therapy for the treatment of chronic venous leg ulcers: A comparative study

BACKGROUND

Chronic venous leg ulcers drastically reduce the quality of life of affected patients. There is heightened interest in autologous platelet-rich plasma (PRP) as one of the promising therapies for leg ulcers.

AIM

Our aim was to compare the clinical efficacy of PRP in the management of chronic venous leg ulcers vs conventional treatment.

PATIENTS/METHODS

In total, 40 patients with chronic venous leg ulcers were included in the study. Twenty patients were treated with autologous PRP weekly for 6 weeks (Group A), and 20 patients were treated with conventional treatment (compression and dressing) for 6 weeks (Group B). Treatment results were calculated by percentage of improvement in area of the ulcer.

RESULTS

Compared to conventional therapy, a highly significant improvement in the ulcer size was observed post-PRP therapy (P-value = .0001). The mean change in the area of the ulcer post-PRP and conventional therapy was 4.92 ± 11.94 cm and 0.13 ± 0.27 cm, respectively, while the mean percentage improvement in the area of the ulcer post-PRP and conventional therapy was 67.6% ± 36.6% and 13.67% ± 28.06%, respectively. Subjective improvement in pain associated with the ulcer was noted by all patients.

CONCLUSIONS

Platelet-rich plasma is a safe nonsurgical procedure for treating chronic venous leg ulcers. Additional studies with larger sample size and longer follow-up periods are required to confirm or refute our findings.

Platelet Rich Plasma Augments Adipose-Derived Stem Cell Growth and Differentiation

BACKGROUND

Adipose-derived stem cells (ASCs) are a powerful tool for cosmetic surgery and regenerative medicine. The use of autologous platelet rich plasma (PRP), particularly in combination with ASC-based therapy, has significantly expanded in recent years. Unfortunately, the mechanisms and optimal dosing responsible for the beneficial effects of PRP remain poorly understood. Here we investigate the effect of PRP on ASC growth and differentiation.

OBJECTIVES

To assess the impact of different PRP feeding and cryopreservation protocols on ASC isolation, expansion, and differentiation.

METHODS

Human PRP was isolated using the Magellan System (Arteriocyte). Fresh PRP (fPRP), flash frozen PRP (ffPRP), and cryopreserved PRP (cPRP) were added to human ASCs isolated from healthy patients. A panel of PRP supplementation protocols was analyzed for ASC adherence, proliferation, and osteogenesis.

RESULTS

The fresh and cryopreserved PRP groups demonstrated reduced cell adherence compared to control (non-PRP) groups (P < 0.001), while the flash frozen PRP groups showed cell adherence equivalent to or better than controls. After 7 days of growth, ASC populations for fPRP and ffPRP Single Administration protocols were significantly higher than other feeding protocols and controls. This benefit was lost in cPRP groups. Optimized ffPRP protocols showed potential for spontaneous osteogenesis.

CONCLUSIONS

Addition of ffPRP improves initial ASC adherence while a single administration of either fresh or flash frozen PRP without additional cell manipulation significantly augments subsequent ASC proliferation. The potential for spontaneous osteogenic differentiation upon PRP exposure invokes the need for additional molecular studies of PRP activity prior to further expansion to clinical applications.

Eye platelet-rich plasma in the treatment of ocular surface disorders

PURPOSE OF REVIEW

Blood-derived products [autologous serum, eye platelet-rich plasma (E-PRP), plasma rich in growth factors] are successful therapies for ocular surface disorders, which compromise the integrity of the cornea surface and conjunctiva.

RECENT FINDINGS

The most noteworthy and recent research has been directed towards hemoderivatives that include platelets. PRP for ophthalmologic use (E-PRP) has achieved successful outcomes as reported in the peer-review literature in the treatment of dry eye, post-laser in-situ keratomileusis ocular surface syndrome, dormant ulcers, and for ocular surface surgical reconstruction after corneal perforation associated to amniotic membrane transplantation, bovine pericardium membrane transplantation, or autologous fibrin membrane combined with solid PRP clot.

SUMMARY

PRP is a portion of the patient's own blood having a platelet concentration above baseline. The main advantage of PRP over other products is the presence of the platelets and associated with this the prolonged release of growth factors that are involved in the wound healing process of the cornea and conjunctival surface. E-PRP seems to be a reliable and effective therapeutic approach to enhance epithelial wound healing and promote ocular surface regeneration in different pathological conditions.

Platelet-Rich Plasma Promotes Axon Regeneration, Wound Healing, and Pain Reduction: Fact or Fiction

Platelet-rich plasma (PRP) has been tested in vitro, in animal models, and clinically for its efficacy in enhancing the rate of wound healing, reducing pain associated with injuries, and promoting axon regeneration. Although extensive data indicate that PRP-released factors induce these effects, the claims are often weakened because many studies were not rigorous or controlled, the data were limited, and other studies yielded contrary results. Critical to assessing whether PRP is effective are the large number of variables in these studies, including the method of PRP preparation, which influences the composition of PRP; type of application; type of wounds; target tissues; and diverse animal models and clinical studies. All these variables raise the question of whether one can anticipate consistent influences and raise the possibility that most of the results are correct under the circumstances where PRP was tested. This review examines evidence on the potential influences of PRP and whether PRP-released factors could induce the reported influences and concludes that the preponderance of evidence suggests that PRP has the capacity to induce all the claimed influences, although this position cannot be definitively argued. Well-defined and rigorously controlled studies of the potential influences of PRP are required in which PRP is isolated and applied using consistent techniques, protocols, and models. Finally, it is concluded that, because of the purported benefits of PRP administration and the lack of adverse events, further animal and clinical studies should be performed to explore the potential influences of PRP.

The effect of red, green and blue lasers on healing of oral wounds in diabetic rats

BACKGROUND AND OBJECTIVE

Many studies have demonstrated that low-level laser therapy (LLLT) can improve wound healing in non-diabetic and diabetic animals. We compared the effects of red, green, and blue lasers in terms of accelerating oral wound healing in diabetic rats.

MATERIAL AND METHODS

Diabetes was successfully induced in 32 male Wistar rats using intraperitoneal injection of Streptozotocin (150 mg/kg). After intraperitoneal injection of the anesthetic agent, a full-thickness oral wound (10 mm × 2 mm) was created aseptically with a scalpel on hard palate of the diabetic rats. The study was performed using red (630 nm), green (532 nm), and blue (425 nm) lasers and a control group. We used an energy density of 2J/cm2 and a treatment schedule of 3 times/week for 10 days. The area of wounds was measured and recorded on a chart for all rats. On the 10th day, the samples were then sacrificed and a full-thickness sample of wound area was prepared for pathological study.

RESULTS

We observed a significant difference (p<0.001) in the mean slope values of wound healing between treatment and control groups. Moreover, the mean slope of wound healing differed significantly between red laser and two other lasers - blue and green (p<0.001). The mean slopes of wound healing were not significantly different between blue laser and green laser (p=0.777).

CONCLUSION

The results of the present study provide evidence that wound healing is slower in control rats compared to the treatment groups. Moreover, the findings suggest that wound healing occurs faster with red laser compared to blue and green lasers.

Autologous platelet rich plasma: topical versus intradermal after fractional ablative carbon dioxide laser treatment of atrophic acne scars

BACKGROUND

A proposal has recently been made regarding the potential adjuvant use of platelet-rich plasma (PRP) with fractional carbon dioxide laser (FCL) for the correction of acne scars.

OBJECTIVE

To compare the efficacy and safety of two administration modes of autologous PRP (intradermal injection (ID) and topical application) after FCL with that of FCL alone in the treatment of atrophic acne scars.

PATIENTS AND METHODS

Thirty patients were randomly divided into two groups. Both underwent split-face therapy. Group 1 was administered FCL followed by ID PRP on one side and FCL followed by ID saline on the other. In group 2, one cheek was treated with FCL followed by ID PRP, and the other received FCL followed by topical PRP. Each patient received 3 monthly sessions. The final assessment took place at 6 months.

RESULTS

Combined PRP- and FCL-treated areas had a significantly better response (p = .03), fewer side effects, and shorter downtime (p = .02) than FCL-treated areas, but there were no significant differences in ID- and topical PRP-treated areas in degree of response and downtime (p = .10); topically treated areas had significantly lower pain scores.

CONCLUSION

The current study introduces the combination of topical PRP and FCL as an effective, safe modality in the treatment of atrophic acne scars with shorter downtime than FCL alone and better tolerability than FCL combined with ID PRP.