Effects of platelet-rich plasma on intestinal anastomotic healing in rats: PRP concentration is a key factor

Current Challenges in the Development of Platelet-Rich Plasma-Based Therapies

Nowadays, biological therapies are booming and more of these formulations are coming to the market. Platelet-rich plasma, or PRP, is one of the most widely used biological therapies due to its ease of obtention and autologous character. Most of the techniques to obtain PRP are focusing on new processes and methods of optimization. However, not enough consideration is being given to modify the molecular components of PRP to generate more effective formulations with the aim of improving PRP treatments. Therefore, this review covers different novel PRP-obtaining methods that attempt to modify the molecular composition of the plasma.

The Efficacy of Local Autologous Platelet-Rich Plasma Prepared by Single and Double Spin Methods in the Treatment of Chronic Ulcer

BACKGROUND

Chronic nonhealing ulcers present significant challenges in diabetic, dermatological, and surgical patients. Platelet-rich plasma (PRP), enriched with bioactive factors, offers promise for wound healing enhancement. This study evaluates PRP's efficacy, prepared via single and double spin methods in nonhealing chronic ulcers.

METHODS

 Twenty-two patients aged 18-65 years participated and 100 mL of blood was drawn into citrate phosphate dextrose adenine (CPDA) bags with all aseptic precautions. PRP was prepared by single and double spin methods. Patient serum and 10% calcium gluconate were added to fibrin gel. PRP was injected around the ulcer and then dressed. Dressings were changed on the fifth, 15th, and 20th days with PRP. Evaluation occurred on day 30 using surface area and volume assessments by both methods.

RESULTS

The single spin PRP group and double spin PRP group had 11 patients each with hemoglobin range of 10.79±1.88 to 12.63±2.22 g/dL. Initial lesions (16.27 cm²) significantly reduced to 14.76 cm² after double spin PRP sessions (p=0.005) and Initial lesions (9.87 cm²) significantly reduced to 7.65 cm² after single spin PRP sessions (p=0.005). Platelet count differences between whole blood and PRP were significant (p<0.05).

CONCLUSIONS

The single spin PRP method exhibited considerable improvements in healing parameters, showcasing its potential for chronic ulcer management.

In-situ gelation of fibrin gel encapsulating platelet-rich plasma-derived exosomes promotes rotator cuff healing

Although platelet-rich plasma-derived exosomes (PRP-Exos) hold significant repair potential, their efficacy in treating rotator cuff tear (RCT) remains unknown. In light of the potential for clinical translation of fibrin gel and PRP-Exos, we evaluated their combined impact on RCT healing and explored suitable gel implantation techniques. In vitro experiments demonstrated that PRP-Exos effectively enhanced key phenotypes changes in tendon stem/progenitor cells. Multi-modality imaging, including conventional ultrasound, shear wave elastography ultrasound, and micro-computed tomography, and histopathological assessments were performed to collectively evaluate the regenerative effects on RCT. The regenerated tendons exhibited a well-ordered structure, while bone and cartilage regeneration were significantly improved. PRP-Exos participated in the healing process of RCT. In-situ gelation of fibrin gel-encapsulated PRP-Exos at the bone-tendon interface during surgery proved to be a feasible gel implantation method that benefits the healing outcome. Comprehensive multi-modality postoperative evaluations were necessary, providing a reliable foundation for post-injury repair.

Pretreatment with platelet-rich plasma protects against ischemia-reperfusion induced flap injury by deactivating the JAK/STAT pathway in mice

BACKGROUND

Ischemia-reperfusion (I/R) injury is a major cause of surgical skin flap compromise and organ dysfunction. Platelet-rich plasma (PRP) is an autologous product rich in growth factors, with tissue regenerative potential. PRP has shown promise in multiple I/R-induced tissue injuries, but its effects on skin flap injury remain unexplored.

METHODS

We evaluated the effects of PRP on I/R-injured skin flaps, optimal timing of PRP administration, and the involved mechanisms.

RESULTS

PRP protected against I/R-induced skin flap injury by improving flap survival, promoting blood perfusion and angiogenesis, suppressing oxidative stress and inflammatory response, and reducing apoptosis, at least partly via deactivating Janus kinase (JAK)-signal transducers and activators of transcription (STAT) signalling pathway. PRP given before ischemia displayed overall advantages over that given before reperfusion or during reperfusion. In addition, PRP pretreatment had a stronger ability to reverse I/R-induced JAK/STAT activation and apoptosis than AG490, a specific inhibitor of JAK/STAT signalling.

CONCLUSIONS

This study firstly demonstrates the protective role of PRP against I/R-injured skin flaps through negative regulation of JAK/STAT activation, with PRP pretreatment showing optimal therapeutic effects.

Advances with Platelet-Rich Plasma for Bone Healing

Despite significant advances in the understanding and delivery of osteosynthesis, fracture non-union remains a challenging clinical problem in orthopaedic surgery. To bridge the gap, basic science characterization of fracture healing provides a platform to identify and target biological strategies to enhance fracture healing. Of immense interest, Platelet-rich plasma (PRP) is a point of care orthobiologic that has been extensively studied in bone and soft tissue healing given its relative ease of translation from the benchtop to the clinic. The aim of this narrative review is to describe and relate pre-clinical in-vitro and in-vivo findings to clinical observations investigating the efficacy of PRP to enhance bone healing for primary fracture management and non-union treatment. A particular emphasis is placed on the heterogeneity of PRP preparation techniques, composition, activation strategies, and delivery. In the context of existing data, the routine use of PRP to enhance primary fracture healing and non-union management cannot be supported. However, it is acknowledged that extensive heterogeneity of PRP treatments in clinical studies adds obscurity; ultimately, refinement (and consensus) of PRP treatments for specific clinical indications, including repetition studies are warranted.

Local injection of platelet-rich plasma offers a new therapeutic option for the treatment of esophagotracheal fistula: a case report

Esophagotracheal fistula (ETF), one of the most serious complications in the treatment of esophageal cancer, presents a complex management challenge. Early diagnosis and treatment are crucial to alleviate clinical symptoms and improve the quality of life of patients with ETF. The most commonly used method for treating ETF is esophageal stenting. However, because of the variable location and size of the fistula, stent placement alone sometimes fails to completely close the fistula, and complications such as fracture and displacement of the esophageal stent may occur. Therefore, safer and more effective methods for the treatment of ETF are required. In recent years, the application of bioactive factors to promote human tissue repair and wound healing has increased and achieved good therapeutic results. We herein describe a case in which we performed endoscopic injection of platelet-rich plasma directly into the ETF site and achieved a favorable outcome. This case suggests that local injection of platelet-rich plasma is a novel treatment modality for ETF.

Pregravid preparation of women with chronic endometritis in IVF cycles

OBJECTIVE

Aim: of our study was to improve the pregravid preparation of women with chronic endometritis to develop individual approaches to overcoming infertility, taking into account the state of endometrium.

PATIENTS AND METHODS

Materials and Methods: The study included 90 women (main group, n=90), 28 to 38 years with an anatomically normal uterus and chronic endometritis (CE). Patients were divided into 2 groups: group I - 45 women with CE who received conventional treatment; group II - 45 women with CE who received pregravid preparation by subendometrial injections of Platelet-Rich Plasma (PRP).

RESULTS

Results: At the first stage of study, the ART statistical reports from 2015 to 2022 were analyzed at the Medical Center of Reproductive Health ≪Damia≫, (Ivano-Frankivsk). Analysis of the vaginal flora parameters before treatment at the first stage revealed the presence of conditionally pathogenic flora in culture from the cervical canal (Candida albicans - 2.4%, Escherihia coli - 4.8%, Staphylococcus epidermidis - 6.2% Enterococcus faecalis - 6.9%), and was evidence of a possible recurrence of inflammation during gestation. In the age category, the groups of patients were homogeneous, with no significant differences by the level of AMH and the level of CD 138. Biochemical pregnancy be present in 20 patients (44.4%) of group I and 28 (62.2%) of group II. Fertility within a year after the end of therapy was restored with the proposed method of therapy in most women (51.1%), in the comparison group this number was 11.1% lower. Pregnancy rate between the groups (I and II) did not differ significantly. The number of live births in group II - 19 births (42.2%) - was 2 times higher than I group (9 (20.0%), P<0.05). The most common complication for women in the comparison groups was early pregnancy loss. Among 18 (40.0%) clinical pregnancies of group I, 8 women (17.8%) had early miscarriage, 1 ectopic pregnancy (2.2%), while in group II clinical pregnancy be present in 23 women (51.1%). The number of terminated pregnancies was two times lower than in the first group (8.9% vs. 17.8%, P<0.05).

CONCLUSION

Conclusions: Chronic endometritis is one of the main causes of pregnancy loss after in vitro fertilization. Patients of the second group were treated with the proposed method of subendometrial injections with Platelet-Rich Plasma (PRP), prepared from autologous blood, is an effective method of preparing the endometrium for embryo transfer and can increase the number of live births in patients with chronic endometritis.

Reinforcement of colon anastomosis healing with leukocyte platelet-rich fibrin in rabbit model

AIM

This study investigated the regenerative efficacy of leukocyte platelet-rich fibrin (L-PRF) on colon anastomotic healing in rabbits.

MAIN METHODS

Thirty-six healthy male white New Zealand rabbits were subjected to complete transactions of the ascending colon. The rabbits were equally divided into two groups: the control group, where the transected colon ends were anastomosed by a simple interrupted suture pattern, and the L-PRF-treated group, in which L-PRF was wrapped entirely around the anastomotic line. The postoperative acute pain scale was assessed using the Bristol Rabbit Pain Scale before surgery and at each four-hour interval post-operatively. After euthanizing the rabbits, the adhesion degree score, anastomotic bursting pressure, and stenosis degree of the anastomotic colon were assessed, and histopathological examination at the 7th, 14th, and 28th days postoperatively.

KEY FINDINGS

Rabbits in both groups showed a significant increase in pain scores compared to baseline. Postoperatively, the L-PRF group exhibited significantly lower pain scores, adhesion scores, and stenosis degrees than the control group. However, the anastomotic bursting pressure was significantly higher in the L-PRF group. Re-epithelialization, polymorphonuclear neutrophil infiltration, granulation tissue formation, and collagen deposition scores were improved considerably in the L-PRF group compared to the control group. Immunostaining of growth factor expression was significantly lower in the control than in the L-PRF group.

SIGNIFICANCE

The L-PRF can augment collagen deposition, re-epithelialize the mucosa, promote angiogenesis, reduce adhesions, and diminish the stenosis degree scores. Therefore, it can be considered a promising aid in healing bowel anastomoses.

Positive Effect of Platelet-Rich Plasma on Neoureterocystostomy in Rats: An Experimental Study

OBJECTIVES

Some of the most common problems after kidney transplant are urologic complications, including ureterocystoanastomosis leakage and stenosis with the development of severe renal graft complications. Isolated plasma contains active substances that cause the activation of various growth factors for the processes of tissue repair or regeneration, has an anti- inflammatory effect, activates angiogenesis, and reduces the risk of infectious complications. Platelet-rich plasma is actively used to stimulate bone regeneration, heal wounds and ulcers on the skin, enhance reconstruction of the larynx and trachea, and ameliorate urethral damage, among other uses. This study was developed to evaluate the positive effect of platelet-rich plasma on the healing process of an anastomotic wound in a model of ureterocystoanas-tomosis in rats.

MATERIAL AND METHODS

We randomized 14 Wistar albino male rats into 2 groups: group 1 included 7 rats that received platelet-rich plasma after ureterocystostomy; group 2 was the control group and included 7 rats that underwent ureterocystostomy without platelet-rich plasma. On postoperative day 7, all animals were euthanized, and the anastomosis area was resected for determination of the tissue hydroxyproline levels and histopathology examination.

RESULTS

Tissue hydroxyproline levels were 767 ± 62.9 μg/g in group 1 and 256 ± 28.0 μg/g in group 2. Tissue hydroxyproline levels were significantly higher in group 1 compared with group 2 (P < .05). There were no significant differences in epithelial damage, acute inflammation, or fibrosis between the tissue samples of both groups.

CONCLUSIONS

The results of this study show that the use of platelet-rich plasma during ureterocystostomy produces a positive effect. Our further research will be devoted to the use of autologous platelet-rich plasma in ureterocystostomy in big models.

Locally Injected Autologous Platelet-Rich Plasma Improves Cutaneous Wound Healing in Cats

Cutaneous defects in cats are commonly encountered in clinical practice, and healing can be accomplished by first or second intention. Platelet-rich plasma (PRP) is characterized by a plasma concentration containing a large number of platelets in a small volume of plasma. The objective of the present study was to record the efficacy of PRP infiltration in open wounds in laboratory cats. Six wounds were created in the dorsal midline of eight laboratory cats, with the wounds of one side designated as the PRP group and the wounds of the other side as the control group. Wound healing was evaluated by daily clinical examination, planimetry, laser Doppler flowmetry, and histologic examination on days 0, 7, 14, and 25, and by measurement of metalloproteinases (MMPs)-2 and -9 and tissue inhibitor metalloproteinase (TIMP)-1 on days 0, 14, and 25. Based on the results of the present study, the mean time for full coverage with granulation tissue was shorter in the PRP group, the mean contraction and total wound healing percentage were increased compared to the control group, and finally, the perfusion measured with laser Doppler flowmetry was higher in the PRP group during all examination days. In conclusion, this is the first study focusing on the topical application of PRP in the treatment of open wounds in laboratory cats, and our results are encouraging—showing a more rapid healing in the PRP group.

Peripheral nerve defects repaired with autogenous vein grafts filled with platelet-rich plasma and active nerve microtissues and evaluated by novel multimodal ultrasound techniques

BACKGROUND

Developing biocompatible nerve conduits that accelerate peripheral nerve regeneration, lengthening and functional recovery remains a challenge. The combined application of nerve microtissues and platelet-rich plasma (PRP) provides abundant Schwann cells (SCs) and various natural growth factors and can compensate for the deficiency of SCs in the nerve bridge, as well as the limitations of applying a single type of growth factor. Multimodal ultrasound evaluation can provide additional information on the stiffness and microvascular flow perfusion of the tissue. This study was designed to investigate the effectiveness of a novel tissue-engineered nerve graft composed of an autogenous vein, nerve microtissues and PRP in reconstructing a 12-mm tibial nerve defect and to explore the value of multimodal ultrasound techniques in evaluating the prognosis of nerve repair.

METHODS

In vitro, nerve microtissue activity was first investigated, and the effects on SC proliferation, migration, factor secretion, and axonal regeneration of dorsal root ganglia (DRG) were evaluated by coculture with nerve microtissues and PRP. In vivo, seventy-five rabbits were equally and randomly divided into Hollow, PRP, Micro-T (Microtissues), Micro-T + PRP and Autograft groups. By analysing the neurological function, electrophysiological recovery, and the comparative results of multimodal ultrasound and histological evaluation, we investigated the effect of these new nerve grafts in repairing tibial nerve defects.

RESULTS

Our results showed that the combined application of nerve microtissues and PRP could significantly promote the proliferation, secretion and migration of SCs and the regeneration of axons in the early stage. The Micro-T + PRP group and Autograft groups exhibited the best nerve repair 12 weeks postoperatively. In addition, the changes in target tissue stiffness and microvascular perfusion on multimodal ultrasound (shear wave elastography; contrast-enhanced ultrasonography; Angio PlaneWave UltrasenSitive, AngioPLUS) were significantly correlated with the histological results, such as collagen area percentage and VEGF expression, respectively.

CONCLUSION

Our novel tissue-engineered nerve graft shows excellent efficacy in repairing 12-mm defects of the tibial nerve in rabbits. Moreover, multimodal ultrasound may provide a clinical reference for prognosis by quantitatively evaluating the stiffness and microvescular flow of nerve grafts and targeted muscles.

Platelet-Rich Fibrin in Fat Grafts for Facial Lipofilling: A Randomized, Controlled Split-Face Clinical Trial

Objective

Previous studies have reported that platelet-rich fibrin (PRF) may enhance the efficacy of fat grafts in facial lipofilling. However, these studies either lacked objective data or were not randomized, controlled trials. Thus, we aimed to objectively evaluate the efficacy of PRF in facial lipofilling.

Methods

A controlled, split-face, randomized trial (January 2018 to May 2019) based on 18 patients who underwent fat grafts for bilateral temple lipofilling was performed. Each patient received a combination of an autologous fat graft and PRF on one side and a fat graft combined with an equal volume of saline on the other side. The effects of PRF were evaluated by comparing the remaining bilateral fat graft volumes through a digital three-dimensional reconstruction technique. Improvements in the appearance and recovery time of each temple were assessed by both a surgeon and patients who were blinded to the treatment assignment. Complications were also recorded.

Results

Bilateral temple lipofilling showed no evidence of fat embolism, vascular/nerve injury, infection, massive edema, or prolonged bruising. Three-dimensional reconstruction data and the assessments from both the surgeon and patients revealed no significant differences in fat graft retention volume between the PRF-positive and PRF-negative lipofilling groups. However, recovery time in the PRF-positive lipofilling sites was significantly shortened compared with that of the PRF-negative lipofilling sites.

Conclusion

Facial filling with autologous fat grafts is effective and safe. Our results show that PRF does not markedly improve fat graft volume retention in the temple but significantly reduces postoperative recovery time.

Trial Registration Number

ChiCTR2100053663.

Therapeutic effect of platelet-rich plasma on glucocorticoid-induced rat bone marrow mesenchymal stem cells in vitro

BACKGROUND

Glucocorticoid-induced osteonecrosis of the femoral head (GIONFH) is a progressive and disabling disease caused by long-term or high-dose glucocorticoid use. Decreased osteogenesis and proliferation of bone marrow mesenchymal stem cells (BMSCs) are the main pathogenesis of GIONFH. Platelet-rich plasma (PRP) has been shown to play a promising role in bone regeneration. However, the effects of PRP on glucocorticoid-induced BMSCs inhibition remains elusive. The objective of this study was to explore whether PRP could improve the in vitro biological activities of BMSCs inhibited by high-dose glucocorticoid in vitro.

METHODS

In this study, a dexamethasone (Dex)-induced in vitro cell model was established. The effects of PRP on proliferation, migration, cell cycle and apoptosis of rat BMSCs induced with high-dose Dex compared to BMSC_CTRL, using CCK-8 assay, transwell, flow cytometry and TUNEL assay, respectively. We further performed the alkaline phosphatase (ALP) and alizarin red (ALR) staining to explore the influence of PRP on osteogenic differentiation. Western Blot was used to detect the expression of Bcl-2, Caspase-3, RUNX2 apoptosis, and osteogenic-related proteins.

RESULTS

We observed increased apoptosis rate and Caspase-3 expression, and the decreased migration and osteogenic differentiation, and down-regulation of RUNX-2 and Bcl-2 expression in Dex-induced BMSCs. PRP could reverse these inhibitory effects of Dex, and enhance the BMSCs proliferation, migration, and osteogenic ability in vitro.

CONCLUSION

Our vitro study showed that PRP significantly protected BMSCs from Dex-induced apoptosis, and further promoted BMSCs proliferation, migration, and osteogenic differentiation. This study provides a scientific basis for the prevention and treatment of GIONFH with PRP. Meanwhile, it also lays the foundation for the application of PRP in other musculoskeletal diseases.

Platelet rich plasma effectiveness in bowel anastomoses: A systematic review

BACKGROUND

Anastomotic leak constitutes a major problem in abdominal surgery. Technical insufficiency, topical or systemic factors contribute to disrupted healing of the performed bowel anastomosis and result in anastomosis leakage, with detrimental effects on patient postoperative outcomes. Despite the investigation of several factors and the invention of protective materials, the ideal agent to prevent anastomotic leaks is yet to be determined.

AIM

To study the effect of platelet rich plasma (PRP) on the healing of bowel anastomoses.

METHODS

A systematic literature search was performed in PubMed, EMBASE, and Scopus databases to identify studies investigating the effect of PRP application on bowel anastomosis.

RESULTS

Eighteen studies were eligible with a total population of 712 animals including rats (14 studies), rabbits (2 studies) and pigs (2 studies). No postoperative complications were reported following PRP application. Fourteen out of 18 studies reported a statistically significant higher anastomosis bursting pressure in PRP groups compared to control either in healthy animals or animal models with underlying condition or intervention, such as intraperitoneal chemotherapy or peritonitis. Similar results were reported by ten studies in terms of tissue hydroxyproline levels. One study reported significant increase in collagen deposition in PRP groups. PRP application resulted in significantly decreased inflammatory cell infiltration in the presence of peritonitis or intraperitoneal chemotherapy (6 studies).

CONCLUSION

The application of PRP is associated with improved bowel anastomosis outcomes, especially in animal models having an underlying condition affecting the normal healing process. PRP application seems to augment the normal healing process under these circumstances. However, further studies are needed to investigate the potential role of PRP on bowel anastomosis healing, especially in clinical settings.

New Technologies to Prevent Anastomotic Leak

Leaks from anastomoses can be a serious complication of any gastrointestinal resection. Leaks lead to increased morbidity, delayed postoperative recovery, and potential delays in adjuvant treatment in cancer cases. Prevention of anastomotic leak has been an area of ongoing research for decades. Methods of assessing bowel perfusion have been developed that may provide forewarning of anastomotic compromise. Physical reinforcement of the anastomosis with buttressing material is an available method employed with the goal of preventing leaks. Liquid-based sealants have also been explored. Lastly, interactions between the gut microbiome and anastomotic healing have been investigated as a mean of manipulating the microenvironment to reduce leak rates. Though no single technology has been successful in eliminating leaks, an understanding of these developing fields will be important for all surgeons who operate on the gastrointestinal tract.

A Web-Based Calculator for Predicting the Occurrence of Wound Complications, Wound Infection, and Unplanned Reoperation for Wound Complications in Patients Undergoing Surgery for Spinal Metastases

BACKGROUND

In the present study, we identified the risk factors for wound complications, wound infection, and reoperation for wound complications after spine metastasis surgery and deployed the resultant model as a web-based calculator.

METHODS

Patients treated at a single comprehensive cancer center during a 7-year period were included. The demographics, pathology, comorbidities, laboratory values, and operative details were collected. Factors with P < 0.15 on univariable regression were entered into multivariable logistic regression to generate predictive models internally validated using 1000 bootstrapped samples.

RESULTS

Of the 330 patients included, 29 (7.6%) had experienced a surgical site infection. The independent predictive factors for wound-related complications were a higher Charlson comorbidity index (CCI; odds ratio [OR], 1.41 per point; P < 0.01), Karnofsky performance scale score ≤70 (OR, 2.14; P = 0.04), lower platelet count (OR, 0.49 per 10⁵/μL; P < 0.01), revision versus index surgery (OR, 3.10; P = 0.02), and increased incision length (OR, 1.21 per level; P = 0.02). Wound infection was associated with a higher CCI (OR, 1.60 per point; P < 0.01), a lower platelet count (OR, 0.35 per 10⁵/μL; P < 0.01), revision surgery (OR, 4.63; P = 0.01), and a longer incision length (OR, 1.25 per level; P = 0.03). Unplanned reoperation for wound complications was predicted by a higher CCI (OR, 1.39 per point; P = 0.003), prior irradiation (OR, 2.52; P = 0.04), a lower platelet count (OR, 0.57 per 10⁵/μL; P = 0.02), and revision surgery (OR, 3.34; P = 0.03), The optimism-corrected areas under the curve were 0.75, 0.81, and 0.72 for the wound complication, infection, and reoperation models, respectively.

CONCLUSIONS

Low platelet counts, poorer health status, more invasive surgery, and revision surgery all independently predicted the risk of wound complications, including infection and unplanned reoperation for infection. Validation of the calculators in a prospective study is merited.

Regenerative and stem cell-based techniques for facial rejuvenation

This review discusses the most novel ideas and modalities being incorporated into facial rejuvenation. Recent innovative techniques include the use of regenerative stem cell techniques and regeneration supportive modalities such as nano-technology or gene therapies. This review aims to investigate approaches that are less well known and lacking established evidence in order to proactively study these techniques prior to them becoming popularized. These applications and relevant research were reviewed in the context of both surgical and non-surgical modalities in clinical practice. Future directions include the concept of "precision cosmetic medicine" utilizing gene editing and cellular therapies to tailor rejuvenation techniques based on each individual's genetic make-up and therefore needs.

Effects of Platelet Rich Plasma and Amniotic Cell Culture Medium on Wound Healing Following Experimental Animal Tracheal Injury Model: A Comparative Study

INTRODUCTION

Prolonged inflammation after tracheal injury invariably results in a degree of stenosis. The topical application of platelet-rich plasma (PRP) and human amniotic fluid-derived cell culture medium (ACCM) have been shown to promote wound healing. The effects of PRP and amniotic cell culture medium (Gibco AmnioMAX - II ) were investigated in a rat model through morphometric, histological, and biochemical parameters.

MATERIAL METHODS

Thirty-two male Sprague Dawley rats were included in the study: 4 rats provided for the preparation of PRP. Three groups of 7 rats were divided into PRP and ACCM groups, a control and a sham group respectively. A transverse incision on the ventral aspect of the third trachea spanning half of the tracheal circumference was performed. The incision was repaired with 7/0 polypropylene in the sham group. In the control group, 0.5 ml saline solution was applied on to the repaired injury site. In the other two groups, 0.5 mL PRP or ACCM were applied topically on the tracheal repair. Tissue samples were harvested 30 days after surgery for morphometric measurements and biochemical analyses for oxidative stress markers, IL-1beta, IL-6, and VEGF. Connective tissue thickness was evaluated histologically. Statistical analysis included the Mann-Whitney U and Kruskal Wallis tests.

RESULTS

A notable difference was detected (P = 0,025) in cartilage segment length measurements of the trachea between the ACCM group and the sham and control groups (P < 0.03). A significant difference was found in the analysis of TAS, TOS, and OSI values between the study groups and the control and sham groups (P < 0.005). There were also differences in IL1-beta and IL-6 levels between ACCM and PRP groups (P < 0.05). For the same parameters, the differences were significant between the PRP and, sham and control groups (P = 0,004 and P = 0,002 respectively), and between the ACCM and, sham and control groups (P = 0,003 and P = 0,002 respectively).VEGF values demonstrated a significant difference between the PRP and sham group (P = 0,002), and between ACCM and sham/control groups (p=0,002 for both), the highest VEGF value was in ACCM group while the lowest value was in the sham group. In the histological assessment of connective tissue, a significant difference was observed between ACCM and the other groups.

CONCLUSION

Amniotic fluid-derived cell culture medium shows less oxidative stress status than the other applications. ACCM is more effective on inflammatory and angiogenetic processes. Connective tissue thickness results were consistent with those biochemical and morphologic results. Additionally, a significant difference was observed in histological data between ACCM and PRP. Overall, ACCM proved to be efficient on tracheal healing. These effects can be attributed to the abundance of growth factors in both PRP and amniotic fluid-derived cell culture medium (ACCM).

The Addition of Tissue Stromal Vascular Fraction to Platelet-Rich Plasma Supplemented Lipofilling Does Not Improve Facial Skin Quality: A Prospective Randomized Clinical Trial

BACKGROUND

Lipofilling has become popular as a treatment to improve aging-related skin characteristics (eg, wrinkles, pigmentation spots, pores, or rosacea). Different additives such as platelet-rich plasma (PRP) or stromal vascular fraction (SVF) have been combined with lipofilling to increase the therapeutic effect of adipose-derived stromal cells (ASCs).

OBJECTIVES

The aim of this study was to examine the hypothesis that mechanically isolated SVF augments the therapeutic effect of PRP-supplemented lipofilling to improve facial skin quality.

METHODS

This prospective, double-blind, placebo-controlled, randomized trial was conducted between 2016 and 2019. In total, 28 female subjects were enrolled; 25 completed the follow-up. All patients received PRP-supplemented lipofilling with either mechanically isolated SVF or saline. SVF was isolated by fractionation of adipose tissue (tSVF). Results were evaluated by changes in skin elasticity and transepidermal water loss, changes in skin-aging-related features, ie, superficial spots, wrinkles, skin texture, pores, vascularity, and pigmentation, as well as patient satisfaction (FACE-Q), recovery, and number of complications up to 1 year postoperative.

RESULTS

The addition of tSVF to PRP-supplemented lipofilling did not improve skin elasticity, transepidermal water loss, or skin-aging-related features. No improvement in patient satisfaction with overall facial appearance or facial skin quality was seen when tSVF was added to PRP-supplemented lipofilling.

CONCLUSIONS

In comparison to PRP-supplemented lipofilling, PRP-supplemented lipofilling combined with tSVF does not improve facial skin quality or patient satisfaction in a healthy population. PRP-supplemented lipofilling combined with tSVF can be considered a safe procedure.

LEVEL OF EVIDENCE: 2

The effectiveness of locally injected platelet-rich plasma on orthodontic tooth movement acceleration

OBJECTIVES

To critically appraise the current evidence available from animal studies pertaining to the effectiveness of platelet-rich plasma (PRP) in accelerating orthodontic tooth movement.

MATERIALS AND METHODS

Electronic searches of nine databases were conducted up to June 2020, followed by a hand search of the reference list of eligible studies. The study design required was prospective controlled animal studies. The primary outcome assessed was the rate of orthodontic tooth movement. The secondary outcome evaluated was histological changes after PRP application. Following study retrieval and selection, relevant data were extracted. Risk-of-bias (RoB) assessment was done using the Systematic Review Center for Laboratory Animal Experimentation's Risk of Bias Tool (SYRCLE's Risk of Bias Tool). Two review authors conducted the work of searching, study selection, and quality assessment independently and in duplicate.

RESULTS

Of 193 studies, 5 animal studies were included in this systematic review. Three studies found a positive correlation between PRP injection and tooth movement acceleration, along with corresponding histological changes. Two studies detected no significant difference in tooth movement rate after PRP application.

CONCLUSIONS

Based on the current limited evidence, the efficacy of PRP on tooth movement acceleration remains debatable. More well-designed randomized controlled trials involving humans are called for to obtain more clinically significant conclusions.

Platlet-Rich Plasma - Review of Literature

Wound healing is a dynamic and physiological process for restoring the normal architecture and functionality of damaged tissue. Platelet-rich plasma (PRP) is an autologous whole blood product that contains a large number of platelets in a small volume of plasma with complete set of coagulation factors, which are in physiological concentrations. PRP has haemostatic, adhesive properties and acts supraphysiologically in the process of wound healing and osteogenesis. Platelets play a very important role in the wound healing process by providing growth factors that enhance the rate and quality of wound healing by many different mechanisms. The aim of this review is to describe: the biology of platelets and their role in the wound healing process, the terminology of platelet rich products, PRP preparation, activation and concentration of PRP, as well as the use of PRP in plastic surgery.

Combining chitin biological conduits with small autogenous nerves and platelet-rich plasma for the repair of sciatic nerve defects in rats

Aims

Peripheral nerve defects are often difficult to recover from, and there is no optimal repair method. Therefore, it is important to explore new methods of repairing peripheral nerve defects. This study explored the efficacy of nerve grafts constructed from chitin biological conduits combined with small autogenous nerves (SANs) and platelet‐rich plasma (PRP) for repairing 10‐mm sciatic nerve defects in rats.

Methods

To prepare 10‐mm sciatic nerve defects, SANs were first harvested and PRP was extracted. The nerve grafts consisted of chitin biological conduits combined with SAN and PRP, and were used to repair rat sciatic nerve defects. These examinations, including measurements of axon growth efficiency, a gait analysis, electrophysiological tests, counts of regenerated myelinated fibers and observations of their morphology, histological evaluation of the gastrocnemius muscle, retrograde tracing with Fluor‐Gold (FG), and motor endplates (MEPs) distribution analysis, were conducted to evaluate the repair status.

Results

Two weeks after nerve transplantation, the rate and number of regenerated axons in the PRP‐SAN group improved compared with those in the PRP, SAN, and Hollow groups. The PRP‐SAN group exhibited better recovery in terms of the sciatic functional index value, composite action potential intensity, myelinated nerve fiber density, myelin sheath thickness, and gastrectomy tissue at 12 weeks after transplantation, compared with the PRP and SAN groups. The results of FG retrograde tracing and MEPs analyses showed that numbers of FG‐positive sensory neurons and motor neurons as well as MEPs distribution density were higher in the PRP‐SAN group than in the PRP or SAN group.

Conclusions

Nerve grafts comprising chitin biological conduits combined with SANs and PRP significantly improved the repair of 10‐mm sciatic nerve defects in rats and may have therapeutic potential for repairing peripheral nerve defects in future applications.

Effects of platelet-rich plasma on spermatogenesis and hormone production in an experimental testicular torsion model

BACKGROUND

Platelet-rich plasma is a biological instrument rich in growth factors and cytokines.

OBJECTIVES

The aim of this study was to investigate the effect of platelet-rich plasma on spermatogenesis and hormone production in an experimental testicular torsion model.

MATERIALS AND METHODS

The rats were randomly divided into three groups, including six rats in each group as follows: the first group as the sham group; the second group as the ischemia/reperfusion + Saline group and the third group as the ischemia/reperfusion + platelet-rich plasma group. The left testicles of the ischemia/reperfusion + Saline and ischemia/reperfusion + platelet-rich plasma group were kept in four-hour torsion. Then, the left testicles of ischemia/reperfusion + Saline and ischemia/reperfusion + platelet-rich plasma groups were detorsioned, and intra-testicular 1 cc saline (ischemia/reperfusion + Saline) and 1 cc platelet-rich plasma (ischemia/reperfusion + platelet-rich plasma) were injected. At one month, blood samples were taken from all groups for hormonal evaluation and left orchiectomy was performed.

RESULTS

The mean follicle-stimulating hormone level of ischemia/reperfusion + Saline group was significantly higher than ischemia/reperfusion + platelet-rich plasma group (7.78 ± 0.23 vs 6.18 ± 0.28 nmol/l, respectively, P = .004). The mean LH level of ischemia/reperfusion + platelet-rich plasma group was significantly lower than ischemia/reperfusion + Saline group (3.63 ± 0.28 vs 5.68 ± 0.21 nmol/l, respectively, P = .004). The mean total testosterone level of ischemia/reperfusion + platelet-rich plasma group was significantly higher than ischemia/reperfusion + Saline group (8.05 ± 0.24 vs 5.78 ± 0.23 nmol/l, respectively, P = .004). The mean Johnsen scores of ischemia/reperfusion + platelet-rich plasma group were significantly higher than ischemia/reperfusion + Saline group (5.85 ± 0.58 vs 3.93 ± 0.65, respectively, P = .004). The mean Johnsen score of the sham group was significantly higher than ischemia/reperfusion + platelet-rich plasma and ischemia/reperfusion + Saline groups (P = .003 and P = .003, respectively).

DISCUSSION AND CONCLUSION

The platelet-rich plasma has beneficial effects on spermatogenesis and reproductive hormone production in testicular torsion. It is easily accessible and applicable. In the future, intra-testicular platelet-rich plasma injection may be used in testicular torsion after detorsion. However, further experimental and large-scale prospective clinical studies are needed to establish a definitive conclusion on this topic.

Variation in platelet-rich plasma compositions used for wound healing indications

At present, the role of platelet-rich plasma (PRP) in burn and wound management is undefined. We present some of the evidence for PRP in wound healing and other medical fields. Currently, the high variation in product composition, mode and timing of application prevent a clear definition of the position of PRP in wound healing. Perspectives on solving these issues are described.

Ultrasound-guided platelet-rich plasma injection and multimodality ultrasound examination of peripheral nerve crush injury

Ultrasound-guided platelet-rich plasma (PRP) injection is able to make up for the limitations of applying a single growth factor. The goal of this study was to investigate the effects of serial ultrasound-guided PRP injections of the appropriate concentration on the treatment of sciatic nerve crush injury, and explore the value of multimodality ultrasound techniques in evaluating the prognosis of crushed peripheral nerve. In vitro, optimal concentration of PRP (from 150%, 250%, 450%, and 650%) was screened due for its maximal effect on proliferation and neurotrophic function of Schwann cells (SCs). In vivo, ninety rabbits were equally and randomly divided into normal control, model, PRP-2.5×, PRP-4.5×, and PRP-6.5× groups. The neurological function and electrophysiological recovery evaluation, and the comparison of the multimodality ultrasound evaluation with the histological results of sciatic nerve crush injury were performed to investigate the regenerative effects of PRP at different concentrations on the sciatic nerve crush injury. Our results showed that the PRP with a 4.5-fold concentration of whole blood platelets could significantly stimulate the proliferation and secretion of SCs and nerve repair. The changes in stiffness and blood perfusion were positively correlated with the collagen area percentage and VEGF expression in the injured nerve, respectively. Thus, serial ultrasound-guided PRP injections at an appropriate concentration accelerates the recovery of axonal function. Multimodality ultrasound techniques provide a clinical reference for prognosis by allowing the stiffness and microcirculation perfusion of crush-injured peripheral nerves to be quantitatively evaluated.

Platelet-rich plasma for the treatment of burn wounds: A meta-analysis of randomized controlled trials

BACKGROUND

To evaluate the efficacy and safety of platelet-rich plasma in the treatment of burn wounds through a meta-analysis of randomized controlled trials.

METHODS

We conducted a comprehensive study from electronic medical journal databases. The primary outcome was healing rate, and the secondary outcomes were healing time, adverse events, pain score and scar score. The data was analyzed using Review Manager 5.3 and Stata 12. The odds ratio (OR) among different groups was calculated by using 95 % confidence interval (CI).

RESULTS

We included 8 randomized controlled trials with a total of 539 patients. The results showed that platelet-rich plasma could improve the healing rate of burn wound (OR 4.43, 95 % CI 2.13-9.22). The wound healing time of the platelet-rich plasma treatment group was significantly shorter than that of the conventional treatment group (OR -4.23, 95 % CI -5.48 to -2.98), both the superficial burn (OR -3.80, 95 % CI -4.53 to -3.07) and the deep burn group (OR -4.65, 95 % CI -6.90 to -2.40) had shorter healing time. Otherwise, the incidences of adverse events (OR 0.30, 95 % CI 0.11-0.78), pain score (OR -0.80, 95 % CI -1.40 to -0.21) and scar score (OR -0.38, 95 % CI -0.69 to -0.07) were all better in the platelet rich plasma treatment group.

CONCLUSION

Topical platelet-rich plasma treatment on burn wounds can improve wound healing and reduce the incidence of adverse events. Further research is needed to standardize the preparation and use of platelet-rich plasma and to evaluate the long-term clinical outcome of platelet-rich plasma in the treatment of burn wounds.

Platelet-rich plasma-Where do we stand today? A critical narrative review and analysis

"Sometimes you have to travel a long way to find what is near." This quote by Paulo Coelho stands true for platelet-rich plasma (PRP) as we know of it today. Large strides have been made to understand this "youth" in blood, but there still seems a long way to go in our understanding of it. Despite advances, clarity in its preparation, biology, and the properties of the final product still remains elusive. The concepts of an ideal number or concentration of platelets in the final enriched plasma, best devices to prepare PRP, an ideal hardware, standard parameters for its preparation, the need for its activation or buffering of the final preparation or whether anticoagulants should be used or not, have evolved, since it was first described. The authors present an analysis of PRP present day status and its usefulness in field of medicine with a review of published literature from "Medline" (via "PubMed"), "Cochrane," the Virtual Health Library, and Google Scholar related to PRP, its biology, types, and classifications, preparation, and use.

Intrauterine infusion of platelet-rich plasma is a treatment method for patients with intrauterine adhesions after hysteroscopy

Objective

To evaluate the efficacy of an intrauterine infusion of platelet‐rich plasma (PRP) in patients with intrauterine adhesions (IUAs).

Methods

A retrospective study was conducted from April 2018 to December 2019 to compare the efficacy of intrauterine infusion of PRP with balloon for patients with IUAs. All patients had moderate or severe IUAs, including 28 patients with intrauterine infusion of PRP (group A), 22 patients with intrauterine balloon (group B), and 20 patients with both intrauterine infusion of PRP and balloon in the first operative hysteroscopy. American Fertility Society (AFS) score and rates of chemical pregnancy were compared.

Results

The AFS score decreased with an average of 5.18 ± 3.93, 4.91 ± 4.39, and 5.15 ± 3.17 comparing the third hysteroscopy with the first operative hysteroscopy in group A, group B, and group C, respectively. No significant differences were found among these groups (P=0.734). The rates of chemical pregnancy were 40.0% in group A, 38.9% in group B, and 33.3% in group C without significant differences (P=0.944).

Conclusion

There were no significant differences between intrauterine infusion of PRP and balloon. PRP is a treatment method for IUAs.

There were no significant differences between intrauterine infusion of platelet‐rich plasma and a balloon, and platelet‐rich plasma is a treatment for intrauterine adhesions.

Vivostat Platelet-Rich Fibrin® for Complicated or Chronic Wounds-A Pilot Study

Vivostat Platelet-Rich Fibrin^® (PRF) is an autologous platelet concentrate used for the local treatment of chronic or complicated wounds. Still, its application for this indication is not evidence-based. Therefore, we performed this monocentric retrospective pilot study investigating the clinical outcome of a local treatment of chronic or complicated wounds in 35 patients (23 male, 12 female, mean age 68.7 years) treated with Vivostat PRF^®. This study population is the largest among published studies analyzing the clinical efficacy of Vivostat PRF^® on chronic wounds so far. Using the perpendicular method we divided the wounds into three sizes (<10, 10–30, and >30 cm²). The clinical efficacy of the Vivostat PRF treatment was the primary endpoint and was divided into three groups of increasing degrees of wound improvement: (1) no improvement of the wound (wound area was not reduced > 10% under Vivostat PRF^® treatment), (2) improvement of the wound (reduced area > 10% under Vivostat PRF^® treatment) and (3) complete epithelialization (wounds that were completely re-epithelialized after Vivostat PRF^® treatment). We included patients’ diagnosis and concomitant diseases (peripheral arterial occlusive disease (PAOD)), chronic venous insufficiency (CVI)), diabetic foot syndrome (DFS)) in our data analysis in order to investigate their potential impact on the wound healing capacity of Vivostat PRF^®. Our results show that in the entire study population, 13 out of 35 (37.1%) patients experienced wound improvement and 14 out of 35 (40%) patients showed complete epithelialization of their wound under Vivostat PRF^® treatment. In summary, 77.1% of the treated patients benefited from the Vivostat PRF^® therapy. These positive wound healing effects were all observed within the first three to six Vivostat PRF^® applications. Subgroup analyses showed that Vivostat PRF^® appeared to be more efficient in patients without CVI in comparison to patients with CVI (p = 0.02). Moreover, Vivostat PRF^® treatment seems to be particularly efficient in PAOD-related wounds with a reduced crural arterial blood supply (p = 0.01). Additionally, we performed an experimental human in vivo study on ten male students where we artificially generated bilateral gluteal wounds and analyzed the influence of the Vivostat PRF^® treatment on the expression of two genes (human beta Defensin-2, ((hBD-2) and human beta-Defensin-3 (hBD-3)) in keratinocytes of resected wound specimens that are induced during wound healing. Interestingly, this analysis revealed that only seven of out ten individuals showed a relevant hBD-2 and hBD-3 gene induction after Vivostat PRF^® treatment. This led to the novel “key-lock-hypothesis”. With the goal of an individualized precision medicine approach with optimized wound treatment strategies in the future, this is an important observation that demands further experimental and clinical studies.

Intra-ovarian injection of platelet-rich plasma into ovarian tissue promoted rejuvenation in the rat model of premature ovarian insufficiency and restored ovulation rate via angiogenesis modulation

Premature Ovarian Insufficiency (POI) is viewed as a type of infertility in which the menopausal status occurs before the physiological age. Several therapeutic strategies have been introduced in clinic for POI treatment, although the outputs are not fully convincing. Platelet-rich plasma (PRP) is a unique blood product widely applied in regenerative medicine, which is based on the releasing of the growth factors present in platelets α-granules. In the current investigation, we examined the effectiveness of PRP as a therapeutic alternative for POI animals. POI in Wistar albino rats was induced by daily intraperitoneal (IP) administration of gonadotoxic chemical agent, 4-vinylcyclohexene dioxide (VCD) (160 mg/ kg) for 15 consecutive days. After POI induction, the PRP solution was directly injected intra-ovarian in two concentrations via a surgical intervention. Every two weeks post-injection, pathological changes were monitored in the ovaries using Hematoxylin-Eosin staining method, until eight weeks. Follicle Stimulating Hormone (FSH) content in serum was measured, together with the expression of the angiogenic-related transcripts ANGPT2 and KDR by real-time qPCR. Furthermore the fertility status of the treated rats was evaluated by mating trials. Histopathological examination revealed successful POI induction via the depletion of morphologically normal follicles in rats following VCD treatment compared to the control rats. The injection of PRP at two concentrations reduced the number and extent of the follicular atresia and inflammatory responses (p < 0.05). The expression of both ANGPT2 and KDR transcripts were significantly increased in POI rats due to enhanced inflammation, while these values were modulated after PRP administration (p < 0.05) compared to POI rats. FSH showed a decreased trend in concentration eight weeks after PRP treatment, but not statistically significant (p > 0.05). Nevertheless, a clear improvement in litter counts was found in POI rats receiving PRP compared to the non-treated POI group, being able to consider PRP as a facile, quick, accessible, safe and relatively cheap alternative therapeutic strategy to revert POI-related pathologies.

The influence of platelet-rich plasma (PRP) on colonic anastomosis healing impaired by intraperitoneal 5-flourouracil application. An experimental study

Purpose

5-flourourasil (5-FU) is commonly used for early intraperitoneal chemotherapy in colorectal or appendiceal cancer patients with peritoneal carcinomatosis. Due to its effect, anastomosis healing can be impaired and leads to anastomotic leakage. In this study, we aimed to investigate the potential healing effect of platelet-rich plasma (PRP) on colonic anastomosis impaired by intraperitoneal 5-flourouracil application.

Methods

After ten rats were sacrificed for preparing PRP, forty Wistar-albino rats were subjected to colonic anastomosis, and randomly allocated into four groups including 10 rats each. According to receiving PRP and/or 5-FU application, the groups were formed as control (C), 5-FU without PRP (CT), anastomosis with PRP (C-PRP), and 5-FU with PRP (CT-PRP). CT and CT-PRP groups also received 5-FU intraperitoneally on postoperative day 1 (POD 1). All animals were euthanized on pod 7. The body weight change, anastomotic bursting pressure (ABP), tissue hydroxiprolin (TH) and histopathological examination of each group were analyzed.

Results

5-FU application significantly reduced ABP levels when compared with group C, C-PRP and CT-PRP (for each comparison, p<0,01). PRP application in CT-PRP group raised the measure of ABP up to the levels of C group. Although tissue hydroxyproline levels (THL) levels of CT-PRP group were found higher than CT group, it was not significant (p=0.112). Microscopically, comparing with CT group, PRP application significantly promoted the healing of colonic anastomosis subjected to 5-FU application by improving tissue edema, necrosis, submucosal bridging and collagen formation (p<0.05). Tissue healing in CT-PRP group was observed as good as the control groups. (C, C-PRP, p=0.181, p=0.134; respectively).

Conclusion

PRP administration on colonic anastomosis significantly promotes the healing process of anastomosis in rats receiving 5-FU. This result encourages further clinical use of PRP to reduce the frequency of AL in patients receiving EPIC.

Comparison of Platelet-Rich Plasma-Impregnated Suture Material with Low and High Platelet Concentration to Improve Colonic Anastomotic Wound Healing in Rats

Objective

This study was designed to investigate the impact of using suture material impregnated with platelet-rich plasma (PRP) in different platelet concentrations on colonic anastomotic wound healing in rats.

Methods

A total of 24 Sprague Dawley female rats were separated into 3 groups (n = 8 for each) including the control group (CON; standard vicryl suture repair), the low platelet concentrate PRP group (L-PRP; suture material impregnated with PRP containing average 2.7-fold (range, 2.0 to 3.1) higher amount of platelets vs. control), and the high platelet concentrate PRP group (H-PRP; suture material impregnated with PRP containing average 5.1-fold (range, 4.8 to 5.4) higher amount of platelets vs. control). Rats were sacrificed on the postoperative 7^th day for analysis of colonic anastomosis region including macroscopic observation, measurement of anastomotic bursting pressure (ABP), and the hydroxyproline levels and histopathological findings in colon tissue samples.

Results

Total injury scores were significantly lower in the L-PRP and H-PRP groups than those in the control group (median (range) 13.00 (7.00) and 11.50 (6.00) vs. 15.50 (4.00), p < 0.05 and p < 0.01, respectively). ABP values (180.00 (49.00) vs. 124.00 (62.00) and 121.00 (57.00) mmHg, p < 0.001 for each) and tissue hydroxyproline levels (0.56 (0.37) vs. 0.25 (0.17) and 0.39 (0.10) μg/mg tissue, p < 0.001 and p < 0.05, respectively) were significantly higher in the L-PRP group as compared with those in the control and H-PRP groups.

Conclusion

In conclusion, our findings revealed PRP application to colonic anastomosis sutures to promote the anastomotic healing process. The platelet concentration of PRP seems to have a significant impact on the outcome with superior efficacy of L-PRP over H-PRP in terms of bursting pressures and collagen concentration at the anastomotic site.

Effect of platelet-rich plasma on colon anastomosis in rats in which hyperthermic intra-peritoneal chemotherapy was performed using 5-fluorouracil

BACKGROUND

Hyperthermic intra-peritoneal chemotherapy (HIPEC) performed in patients with peritoneal carcinomatosis has a cytotoxic effect on tumour cells. This cytotoxic effect also adversely affects the wound healing of anastomosis, which is frequently undertaken in this patient group, and causes anastomotic leakage and intestinal fistulas. Platelet-rich plasma (PRP) gel has been used in wound healing and has shown efficacy. We investigated the effect of PRP gel on colon anastomosis healing in rats treated with 5-fluorouracil (5-FU).

METHODS

Twenty-four rats were divided into three groups, each containing eight rats: group 1 (control) underwent colon anastomosis alone; group 2 (5-FU) underwent a colon anastomosis and HIPEC; and group 3 (5-FU + PRP) underwent a colon anastomosis and HIPEC and received topical PRP gel. The rats were sacrificed on the post-operative day 7 and the anastomotic bursting pressure (ABP) was measured. Tissue samples were obtained to measure the hydroxyproline level and investigate the histopathological changes on the anastomosis line.

RESULTS

ABP was higher in the control and 5-FU + PRP groups than in the 5-FU group (P = 0.009, P = 0.047). The tissue hydroxyproline levels were higher in the control and 5-FU + PRP groups than in the 5-FU group (P = 0.001, P = 0.030). The histopathological findings of the 5-FU + PRP group were better than those of the 5-FU group.

CONCLUSION

This study showed that the application of PRP gel to colon anastomoses increased ABP in rats treated with HIPEC using 5-FU. It also showed positive effects on anastomotic healing by increasing the tissue hydroxyproline levels on the anastomosis line and reducing the inflammatory response.

Is platelet-rich plasma improves the anastomotic healing in hyperthermic intraperitoneal chemotherapy with oxaliplatin: an experimental rat study

Purpose

Hyperthermic intraperitoneal chemotherapy (HIPEC) is a novel treatment option for peritoneal surface malignancies. Due to cytotoxic effects of chemotherapeutic agents, anastomosis healing can be impaired and lead to leakage rates higher than conventional intestinal surgery. In this experimental study, we aimed to investigate the effects of platelet-rich plasma (PRP) on colonic anastomosis in rats that received HIPEC with oxaliplatin.

Methods

Thirty rats were divided into 3 groups. Group 1 was determined as control group and hyperthermic saline perfusion was performed after colon anastomosis. In group 2, colon anastomosis then hyperthermic oxaliplatin perfusion was performed. In the last group, the colonic anastomosis was enhanced by PRP gel and then hyperthermic oxaliplatin perfusion was performed. All the rats were reoperated on postoperative day 7 and anastomotic bursting pressure values were recorded. Tissue samples were taken for hydroxyproline assay and histopathological examination.

Results

Control group had higher anastomotic bursting pressure value than group 2 and group 3 (P < 0.001). There were significant differences in anastomotic bursting pressure between groups 2 and 3 (P < 0.001). Group 2 had significantly lower hydroxyproline levels than group 3 and control group (P < 0.001). Histopathological examination revealed that PRP application reduced inflammatory response.

Conclusion

PRP application on colonic anastomosis improves anastomotic healing and can reduce anastomosis related complications and stoma creation; though further clinical studies are needed.

Effects of autologous platelet-rich plasma coated sutures on intestinal anastomotic healing in rabbits

The objective of this study was to investigate the intestinal anastomotic healing enhancing effect of platelets-rich plasma (PRP) using PRP-coated sutures in a rabbit model. A total of 30 mature male rabbits were divided into 3 groups (10 rabbits per group). Group 1 received uncoated sutures, group 2 received sodium acetate-coated sutures, and group 3 received PRP-coated sutures. Polyglactin 910 (Vicryl, USA), size 4-0 was used in all groups. Five rabbits of each group were euthanized on day 3 following the surgery while the remaining 5 rabbits were euthanized on day 10. Gross evaluation of the anastomotic site in PRP-coated sutures group demonstrated significantly (P < 0.05) lower adhesion formation scores on both days 3 and 10 of the study while in the control groups, evidence of leakage at the anastomotic site was present along with signs of haemorrhage and local inflammation. On day 10 in the control groups, there were strands of strong adhesions between the ileum, colon and cecum with large amount of fibrin deposited at the site of the anastomosis. Tissues of the anastomotic site revealed a significant level of hydroxyproline on day 10 in PRP-coated sutures group compared with control groups. Histopathological evaluation revealed significantly (P < 0.05) less inflammatory infiltration, and more angiogenesis and collagen deposition on day 10 in PRP-coated sutures group compared to the control groups. Results of this study clearly indicate promising healing enhancing effects of using PRP-coated sutures at intestinal anastomotic site with little to no obvious disadvantages.

Freeze-Dried Platelet-Rich Plasma Induces Osteoblast Proliferation via Platelet-Derived Growth Factor Receptor-Mediated Signal Transduction

Study Design

Controlled laboratory study.

Purpose

This study aimed to evaluate the in vitro pharmacological activity of growth factors (GFs) in freeze-dried platelet-rich plasma (FD-PRP) after storage for 4 weeks.

Overview of Literature

Freshly prepared PRP is a rich source of many GFs. We reported that FD-PRP stored for 8 weeks accelerated bone union in a rat posterolateral fusion model equally well as fresh-PRP. However, the pharmacological activity of FD-PRP after long-term storage has not been shown in vitro.

Methods

Immediately after preparation, as well as 4 weeks after freeze-dried storage, the platelet count was measured. Human osteoblasts were treated with fresh-PRP and FD-PRP, respectively. Western blotting was used to assess the phosphorylation of the platelet-derived growth factor (PDGF) receptor (PDGFR) and its downstream target, extracellular signal-regulated kinase (ERK). The proliferation rates of osteoblasts were investigated by immunocytochemistry and MTT cell viability assays. Furthermore, we used western blotting to evaluate the effect of PDGFR knockdown on the phosphorylation of ERK stimulated with fresh-PRP and FD-PRP.

Results

Platelet counts in both the fresh-PRP and FD-PRP samples were approximately 10-fold higher than in peripheral blood samples. The phosphorylation and activation of the PDGFR and ERK were evenly induced by fresh-PRP and FD-PRP stimulation. Both freshPRP and FD-PRP significantly induced osteoblast proliferation in MTT cell viability assays. Furthermore, osteoblast PDGFR knockdown attenuated the downstream ERK activation by fresh PRP and FD-PRP.

Conclusions

We demonstrated the pharmacological activity of PDGF in FD-PRP in vitro after 4 weeks of storage.

Platelet-Rich Plasma Combined with Low-Dose Ultrashort Wave Therapy Accelerates Peripheral Nerve Regeneration

Finding treatments that accelerate peripheral nerve regeneration, prolongation, and functional recovery remains a challenging task. Platelet-rich plasma (PRP) contains numerous growth factors and active proteins, and low-dose ultrashort waves (USWs) stimulate the formation of nerve-nourishing vessels, which are powerful for nerve regeneration. The goal of this study was to evaluate the synergistic effects of serial ultrasound-guided PRP injections combined with low-dose USWs radiation on peripheral nerve regeneration in a crush injury model. Fifty rabbits were equally and randomly divided into normal control, model, USW, PRP, and PRP+USW groups. The neurological function, electrophysiological recovery, and histological and morphological evaluation of regenerated nerves, as well as a targeted muscle recovery assessment, were performed to investigate the regenerative effect of PRP combined with USW therapy. Our results showed that the PRP+USW group had the better early axonal regeneration and displayed the earliest positive compound muscle action potential among the treatment groups. At postintervention week 12, a histological evaluation showed similar expression of the S-100 protein in the PRP+USW and normal control groups. Moreover, the morphological assessment revealed a significant increase in the myelinated nerve fiber density and diameter and myelin sheath thickness compared with the USW and PRP groups. The morphometry of the target muscles indicated the lowest reduction in the percent volume in the PRP+USW group, and an ultrasound examination of the targeted muscle showed the best improvement in stiffness and perfusion parameters at 12 weeks after crush injury. Thus, serial ultrasound-guided PRP injections combined with low-dose USW radiation exert a synergistic effect on accelerating functional axon recovery and decreasing atrophy of the target muscles in a crush injury model. Impact Statement This research describes that the application of platelet-rich plasma combined with low-dose ultrashort waves treatment exert a synergistic effect on accelerating peripheral nerve regeneration. With the extensive use of platelet-rich plasma and physical factors in regenerative medicine or clinical rehabilitation medicine, our findings may help establish effective strategies for repairing peripheral nerve injury.

The effects of platelet-rich-plasma gel application to the colonic anastomosis in hyperthermic intraperitoneal chemotherapy: An experimental rat model

Hyperthermic intraperitoneal chemotherapy (HIPEC) has cytotoxic effects on tumour cells but also negative impacts on anastomotic healing. Platelet-rich-plasma (PRP) is used for wound care but data about effects on gastrointestinal anastomosis are limited. In this experimental study, we aimed to investigate the effects of PRP application on colon anastomosis in rats those received HIPEC with cisplatin. Five rats were sacrificed to obtain PRP gel. Thirty rats were divided into three groups; Group 1: control group, Group 2: colon anastomosis and HIPEC with cisplatin, and Group 3: colon anastomosis enhanced by PRP and HIPEC with cisplatin. The rats were re-operated on postoperative day seven and anastomotic bursting pressure (ABP) was recorded. Also, tissue samples were taken for hydroxyproline assessment and histopathological examination. There were significant differences in ABP between Groups 2 and 3, and also those groups had lower ABP compared with the control group. Group 3 had significantly higher hydroxyproline levels and had better histopathological findings than group 2. According to our findings, we suggest that PRP application improves the anastomotic healing by increasing anastomotic bursting pressure, hydroxyproline levels, and decreasing inflammatory response. Further clinical studies are needed to prove our hypothesis.

Platelet-rich plasma affects the proliferation of canine bone marrow-derived mesenchymal stromal cells in vitro

BACKGROUND

Reported efficacy of platelet-rich plasma (PRP) in regenerative medicine is contradictory. We validated the effects of PRP on proliferation of canine bone marrow-derived multipotent mesenchymal stromal cells (K9BMMSCs) in vitro. PRP was extracted from blood of six dogs with osteoarthritis. K9BMMSCs were established from bone marrow and characterized for CD90 and CD19 expression by immunocytochemistry. Effects of PRP concentrations on viability of matching autologous K9BMMSCs were validated using MTS assay.

RESULTS

Positive CD90 and negative CD19 expression confirmed MSC origin. PRP at 40% volume/volume concentration increased, while PRP at 80 and 100% v/v concentrations suppressed viability of tested K9BMMSCs.

CONCLUSION

PRP concentration plays an important role in K9BMMSCs viability, which could affect tissue repairs in vivo.

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).

Application of standardized platelet-rich plasma in elderly patients with complex wounds

In recent years, autologous platelet-rich plasma (PRP) derivatives have been used widely in the regeneration and repair of tissue, but a standard definition and preparation method for PRP are lacking. We developed a standardized method using platelet indices as quality-control indicators for PRP preparation. Twenty-one elderly patients (9 males, 12 females) with complex wounds were treated with standardized platelet-rich plasma (S-PRP). The platelet count in PRP after the second centrifugation was 1,069-1,436 × 10⁹ /L. We adjusted the platelet concentration in PRP after a second centrifugation to 1,000 × 10⁹ /L according to a formula using platelet-poor plasma (PPP). The standardized preparation method that we developed gave S-PRP with a relatively uniform platelet concentration. The wounds of 21 patients showed accelerated healing after S-PRP treatment, and there were no obvious side effects during treatment. These data suggest that our preparation method of S-PRP, using platelet indices as quality-control indicators with platelet count of 1,000 × 10⁹ /L could be used for the treatment of complex wounds in the elderly. The preparation method of S-PRP proposed in the present study may be a simple and effective method of PRP quality control.

Review of concentration yields in commercially available platelet-rich plasma (PRP) systems: a call for PRP standardization

Platelet-rich plasma (PRP) has become increasingly popular in pain medicine with hopes of becoming a safe, effective alternative to routine treatments. However, given its autologous nature, PRP injectate may differ depending on the specific manufacturer and protocol. Currently, there is no standardization of reporting protocol. This systematic review compiles and standardizes values on PRP preparation and final product composition of platelets, white cell count, and growth factors for ease of comparison. On review of 876 studies, 13 studies were selected according to our inclusion criteria. Data from 33 PRP systems and protocols were extracted and standardized. Overall, PRP final product concentrations as well as PRP preparation protocols varied widely between systems. However, platelet concentration was directly correlated with both volume of blood collected and device centrifugal force. In conclusion, there is a large heterogeneity between PRP separation systems that must be resolved for proper study of this promising treatment.

Evaluate the effects of platelet rich plasma (PRP) and zinc oxide ointment on skin wound healing

In this study efficiency of platelet rich plasma (PRP) and zinc oxide on full thickness wounds created on rabbits was researched. This study conducted on 24 New Zealand rabbits divided 2 groups. A circular of 1.5 × 1.5 cm (2.5 cm²) full thickness skin wound was created under the general anesthesia. 1 ml PRP (5.503106/mm³) was applied to the one of the wounds subcutaneously. To the other wound 1 mm³ zinc oxide ointment was applied once a day during the study. Wound contraction rates were measured, biopsy materials were collected and evaluated macroscopically and histopathologically postoperatively 3rd, 7th and 15th days. As a result it is determined that PRP and zinc oxide accelerated wound contraction rates between the groups were determined as 3rd day p = 0.007, 7th day p = 0.0002 and 15th day p = 0.002.

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Wound healing is inborn to all species and is the biologic procedure by which the body repairs itself after injury, whichever it be traumatic, complicated, infected and/or surgical.

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Platelet rich plasma (PRP) gel is measured to be progressive wound treatment for acute and chronic wounds. PRP gel has mainly been applied to improve or accelerate healing of wound.

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Zinc is a vital trace element in the human body and its significance in wellbeing and infection is valued. Zinc deficiency of genetic or dietary cause can prompt neurotic, pathologic and physiological changes and deferred wound healing.

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Topical treatment with autologous PRP can be used as clinical therapy and can enhance tissue healing and enhanced angiogenesis compared to zinc oxide treatments.