RevaTen platelet-rich plasma improves cardiac function after myocardial injury

Effect of autologous platelet-rich plasma on patients with acute type A aortic dissection underwent aortic arch replacement: A retrospective cohort study

BACKGROUND

Coagulopathy and massive bleeding are common complications of patients with Stanford type A acute aortic dissection repair, and patients with these complications require many transfusions. Autologous platelet-rich plasma (PRP) is widely used to reduce the need for blood products. In the present study, we aimed to investigate the effects of PRP on blood conservation and the postoperative conditions of patients who underwent aortic arch replacement.

METHODS

Patients with aortic dissection undergoing aortic arch replacement were included initially application In all, 837 patients were divided into the PRP and non-PRP groups according to PRP use, whereupon a propensity score match was performed. The data analyzed included patient basic information, intraoperative information, postoperative biochemical examinations, and CTA reports.

RESULTS

In total, 610 patients were finally included (305 patients per group). Groups were well balanced after matching. Compared to the non-PRP group, less cryoprecipitate was transfused in the PRP group (10.0 [7.5, 11.0] vs. 10.0 [10.0, 11.5], P = 0.021), while no differences were found in packed RBC, FFP, and platelets between the two groups. Also, the surgery variables showed no differences. After surgery, patients in the PRP group showed higher postoperative serum albumin (36.43±4.20 vs. 35.39±4.40 g/L, P = 0.004) and total protein levels (59.38±6.25 vs. 58.06±7.19 g/L, P = 0.019) than the non-PRP group, but no significant differences in the levels of ALT, AST, Scr, and BUN. CTA reports showed that the proportion of patients with pleural effusion was lower in the PRP group (76.66% vs. 83.99%, OR = 1.59, 95% CI: 1.04-2.45, P = 0.028), while the proportions of pericardial effusion were not significantly different.

CONCLUSIONS

PRP application in aortic arch replacement surgery reduced the transfusion of cryoprecipitate, increased the postoperative serum albumin and total protein levels, and reduced the incidence of pleural effusion. No effect of PRP application was found on other postoperative blood indicators and CTA reports.

Platelet-rich plasma exhibits anti-inflammatory effect and attenuates cardiomyocyte damage by reducing NF-κB and enhancing VEGF expression in isoproterenol induced cardiotoxicity model

The present study investigated the cardioprotective effects of activated platelet-rich plasma (PRP) on high dose isoproterenol (ISO) induced cardiotoxicity. ISO was injected at a dose of 85 mg/kg/day, s.c. for 2 days. Cardiac function parameters including dp/dt max/min, left ventricular end diastolic pressure (LVEDP), relaxation constant (tau) and electrocardiogram (ECG) changes, anti-oxidant and membrane bound enzymes assays, pro-inflammatory cytokine levels, collagen content, immunohistochemical staining/gene expression of vascular endothelial growth factor (VEGF), cTnI (cardiac troponin I), NF-κB (nuclear factor kappa B), Smad-2/3, TGF-β (transforming growth factor), collagen-1/3 proteins were evaluated. PRP and platelet-poor plasma (PPP) were injected intramyocardially (200 μl in each ventricle region) 3 h after first dose of ISO under anesthesia. ISO injection induced cardiac dysfunction, hypertrophy, fibrosis, necrosis due to decline in anti-oxidant capacity, enhanced NF-κB and reduced cTnI immunostaining. However, the PRP injection attenuated these cardiac pathological changes by exerting anti-inflammatory properties and promoting cardiomyocyte repair.

Role of platelet rich plasma mediated repair and regeneration of cell in early stage of cardiac injury

Platelet-rich plasma (PRP) is a widely accepted treatment approach and has heightened the quality of care among physicians. PRP has been used over the last decade to boost clinical results of plastic therapies, periodontal surgery and intra-bony defects. According to certain research, elevated levels of PRP growth factors that could promote tissue repair and have the potential for PRP to be beneficial in regenerating processes that Maxillofacial and Oral Surgeons, Veterinary Officers, Athletic medicine specialists and Dermatologists have long admired. PRP is an autologous whole blood fraction that has a heavy amount of a variety of growth factors such as epidermal growth factor (EGF), Vascular Endothelial Growth Factor (VEGF), hepatocyte growth factor (HGF), fibroblast growth factors (FGFs), transforming growth factor beta-1 (TGF-b), insulin-like growth factor-I (IGF-I) and platelet-derived growth factor (PDGF) which can facilitate repair and regeneration. Moreover, a clinical trial of PRP in severe angina patients has shown its excellent safety profile. However, PRP is a very complex biological substance with an array of active biomolecules, its functions are yet to be fully clarified. In-addition, there was insufficient work assessing possible cardiovascular tissue benefits from PRP. Thus, it still remains necessary to identify the most clinically important cardiovascular applications and further research in clinical scenario need to be validated.

Effects of platelet rich plasma on experimentally induced diabetic heart injury

Diabetic heart is one of the common complications of diabetes mellitus. Platelet-rich plasma (PRP) is an autologous product rich in growth factors that can enhance tissue regeneration. This work was conducted to study the PRP ability to improve diabetes-inducing cardiac changes. Also, it sheds more light on the possible mechanisms through which PRP induces its effects. Rats were divided into; control, PRP, diabetic, and PRP-diabetic groups. Cardiac specimens were obtained and processed for biochemical, histological, and immunohistochemical study. The diabetic group exhibited a significant increase in cardiac oxidative stress, inflammation, and cardiac injury markers if compared with the control group. Additionally, the cardiac tissue showed variable morphological changes in the form of focal distortion and loss of cardiac myocytes. Distorted mitochondria and heterochromatic nuclei were observed in the cardiac muscle fibers. The mean number of charcoal-stained macrophages, and mean area fraction for collagen fibers, mean number of PCNA-immune positive cardiac muscle were significantly decrease in PRP- diabetic group. Collectively, the results showed that PRP treatment ameliorated most of all these previous changes. CONCLUSION: PRP ameliorated the diabetic cardiac injury via inhibition of oxidative stress and inflammation. It was confirmed by biochemical, histological, and immunohistochemical study. It could be concluded that PRP could be used as a potential therapy for diabetic heart.

Therapeutic Efficacy of Autologous Platelet Concentrate Injection on Macular Holes with High Myopia, Large Macular Holes, or Recurrent Macular Holes: A Multicenter Randomized Controlled Trial

We aimed to evaluate the anatomical and functional outcomes of pars-plana vitrectomy (PPV) with or without autologous platelet concentrate (APC) injection in patients with recurrent macular holes (MHs), large MHs, or MHs with high myopia. This multicenter, prospective, interventional randomized controlled trial was conducted from March 2017 to April 2020. Participants were randomly allocated to a PPV group or a PPV+APC group. All participants underwent standard 25-gauge PPV, and eyes in the PPV+APC group underwent PPV with intravitreal APC injection before air-gas exchange. A total of 117 patients were enrolled (PPV group: n = 59, PPV+APC group: n = 58). Hole closure was achieved in 47 participants (79.7%) in the PPV group and 52 participants (89.7%) in the PPV+APC group. There were no between-group differences in the anatomical closure rate or functional outcomes including best-corrected visual acuity, metamorphopsia, pattern-reversal visual evoked potential, or Visual Function Questionnaire-25 score. The use of APC injection does not improve the anatomical and functional outcomes of surgery for large MHs, recurrent MHs, or MHs with high myopia. The adjunctive use of APC can be considered in selected cases because it is not inferior to conventional MH surgery, is relatively simple to perform, and is not affected by the surgeon’s skill.

PRP in wound healing applications

Platelets play a crucial role in hemostasis, tissue regeneration and host defense. Based on these settings, platelet-rich plasma (PRP) and its derivatives are therapeutically used to promote wound healing in several scenarios. This review summarizes the biological mechanisms underlying the most traditional as well as innovative applications of PRP in wound healing. These mechanisms involve the combined action of platelet-derived growth factors and cytokines, together with the role of plasma-derived fibrillar, antioxidant and homeostatic factors. In addition, regenerative treatments with PRP consist of personalized and non-standardized methods. Thus, the quality of PRP varies depending on endogenous factors (e.g., age; gender; concomitant medication; disease-associated systemic factors; nutrition) and exogenous factors (anticoagulants and cellular composition). This review also analyses whether these factors affect the biological mechanisms of PRP in wound healing applications.

Antioxidant and Biological Properties of Mesenchymal Cells Used for Therapy in Retinitis Pigmentosa

Both tissue repair and regeneration are a priority in regenerative medicine. Retinitis pigmentosa (RP), a complex retinal disease characterized by the progressive loss of impaired photoreceptors, is currently lacking effective therapies: this represents one of the greatest challenges in the field of ophthalmological research. Although this inherited retinal dystrophy is still an incurable genetic disease, the oxidative damage is an important pathogenetic element that may represent a viable target of therapy. In this review, we summarize the current neuroscientific evidence regarding the effectiveness of cell therapies in RP, especially those based on mesenchymal cells, and we focus on their therapeutic action: limitation of both oxidative stress and apoptotic processes triggered by the disease and promotion of cell survival. Cell therapy could therefore represent a feasible therapeutic option in RP.

Mesenchymal stem cell surgery, rescue and regeneration in retinitis pigmentosa: clinical and rehabilitative prognostic aspects

Purpose:

To assess whether treatment with the Limoli Retinal Restoration Technique (LRRT) can be performed in patients with retinitis pigmentosa (RP), grafting the autologous cells in a deep scleral pocket above the choroid of each eye to exert their beneficial effect on the residual retinal cells.

Methods:

The patients were subjected to a complete ophthalmological examination, including best corrected visual acuity (BCVA), close-up visus measurements, spectral domain-optical coherence tomography (SD-OCT), microperimetry (MY), and electroretinography (ERG). Furthermore, the complete ophthalmological examination was carried out at baseline (T0) and at 6 months (T180) after surgery. The Shapiro–Wilk test was used to assess the normality of distribution of the investigated parameters. A mixed linear regression model was used to analyse the difference in all the studied parameters at T0 and T180, and to compare the mean change between the two groups. All statistical analyses were performed with STATA 14.0 (Collage Station, Texas, USA).

Results:

LRRT treatment was performed in 34 eyes of 25 RP patients recruited for the study. The eyes were classified in two groups on the basis of foveal thickness (FT) assessed by SD-OCT: 14 eyes in Group A (FT≤190μm) and the remaining 20 ones in Group B (FT > 190μm). Although it had not reached the statistical significance, Group B showed a better improvement in BCVA, residual close-up visus and sensitivity than Group A.

Conclusions:

Previous studies have described the role of LRRT in slowing down retinal degenerative diseases. Consequently, this surgical procedure could improve the clinical and rehabilitative prognostic parameters in RP patients. On the other hand, further clinical research and studies with longer follow-up will be needed to evaluate its efficacy.

Analyzing Impetus of Regenerative Cellular Therapeutics in Myocardial Infarction

Both vasculature and myocardium in the heart are excessively damaged following myocardial infarction (MI), hence therapeutic strategies for treating MI hearts should concurrently aim for true cardiac repair by introducing new cardiomyocytes to replace lost or injured ones. Of them, mesenchymal stem cells (MSCs) have long been considered a promising candidate for cell-based therapy due to their unspecialized, proliferative differentiation potential to specific cell lineage and, most importantly, their capacity of secreting beneficial paracrine factors which further promote neovascularization, angiogenesis, and cell survival. As a consequence, the differentiated MSCs could multiply and replace the damaged tissues to and turn into tissue- or organ-specific cells with specialized functions. These cells are also known to release potent anti-fibrotic factors including matrix metalloproteinases, which inhibit the proliferation of cardiac fibroblasts, thereby attenuating fibrosis. To achieve the highest possible therapeutic efficacy of stem cells, the other interventions, including hydrogels, electrical stimulations, or platelet-derived biomaterials, have been supplemented, which have resulted in a narrow to broad range of outcomes. Therefore, this article comprehensively analyzed the progress made in stem cells and combinatorial therapies to rescue infarcted myocardium.

Useful applications of growth factors for cardiovascular regenerative medicine

Novel advances for cardiovascular diseases (CVDs) include regenerative approaches for fibrosis, hypertrophy, and neoangiogenesis. Studies indicate that growth factor (GF) signaling could promote heart repair since most of the evidence is derived from preclinical models. Observational studies have evaluated GF serum/plasma levels as feasible biomarkers for risk stratification of CVDs. Noteworthy, two clinical interventional published studies showed that the administration of growth factors (GFs) induced beneficial effect on left ventricular ejection fraction (LVEF), myocardial perfusion, end-systolic volume index (ESVI). To date, large scale ongoing studies are in Phase I-II and mostly focussed on intramyocardial (IM), intracoronary (IC) or intravenous (IV) administration of vascular endothelial growth factor (VEGF) and fibroblast growth factor-23 (FGF-23) which result in the most investigated GFs in the last 10 years. Future data of ongoing randomized controlled studies will be crucial in understanding whether GF-based protocols could be in a concrete way effective in the clinical setting.

F13A1 Gene Variant (V34L) and Residual Circulating FXIIIA Levels Predict Short- and Long-Term Mortality in Acute Myocardial Infarction after Coronary Angioplasty

Factor XIIIA (FXIIIA) levels are independent predictors of early prognosis after acute myocardial infarction (AMI) and the Valine-to-Leucine (V34L) single nucleotide polymorphism (SNP) seems associated with lower AMI risk. Since the long-term AMI prognosis merits deeper investigation, we performed an observational study evaluating relationships between FXIIIA residual levels, cardiovascular risk-factors, and inherited genetic predispositions. FXIIIA V34L was genotyped in 333 AMI patients and a five-year follow-up was performed. FXIIIA levels assessed at day-zero (d0) and four days after AMI (d4), and conventional risk factors were analyzed, focusing on the development of major adverse cardiovascular events (MACE). FXIIIA assessed at d0 and d4 was also an independent MACE predictor in the long-term follow-up (FXIIIA_d0, Odds Ratio (OR) = 3.02, 1.79–5.1, p = 0.013; FXIIIA_d4, OR = 4.46, 2.33–8.55, p = 0.0001). FXIIIA_d4 showed the strongest MACE association, suggesting that the FXIIIA protective role is maximized when high levels are maintained for longer time. Conversely, FXIIIA levels stratified by V34L predicted MACE at a lesser extent among L34-carriers (Hazard Risk (HR)_VV34 = 3.89, 2.19–6.87, p = 0.000003; HR_L34-carriers = 2.78, 1.39–5.57, p = 0.0039), and V34L did not predict all MACE, only multiple-MACE occurrence (p = 0.0087). Finally, in survival analysis, heart failure and death differed significantly from stroke and recurrent ischemia (p = 0.0013), with FXIIIA levels appreciably lower in the former (p = 0.05). Overall, genetically-determined FXIIIA levels have a significant long-term prognostic role, suggesting that a pharmacogenetics approach might help to select those AMI patients at risk of poor prognosis in the need of dedicated treatments.

Patient-Specific Bioinks for 3D Bioprinting of Tissue Engineering Scaffolds

Bioprinting has emerged as a promising tool in tissue engineering and regenerative medicine. Various 3D printing strategies have been developed to enable bioprinting of various biopolymers and hydrogels. However, the incorporation of biological factors has not been well explored. As the importance of personalized medicine is becoming more clear, the need for the development of bioinks containing autologous/patient-specific biological factors for tissue engineering applications becomes more evident. Platelet-rich plasma (PRP) is used as a patient-specific source of autologous growth factors that can be easily incorporated to hydrogels and printed into 3D constructs. PRP contains a cocktail of growth factors enhancing angiogenesis, stem cell recruitment, and tissue regeneration. Here, the development of an alginate-based bioink that can be printed and crosslinked upon implantation through exposure to native calcium ions is reported. This platform can be used for the controlled release of PRP-associated growth factors which may ultimately enhance vascularization and stem cell migration.

Effects of platelet-rich plasma against experimental ischemia/reperfusion injury in rat testis

BACKGROUND

Testicular torsion is a common problem and, to date, there is no agent to preserve testicular function following detorsion. Platelet-rich plasma (PRP), with its rich growth factor composition, has proven beneficial in regenerative therapy. It is believed that PRP has not been studied in testis for ischemia/reperfusion (I/R) injury.

OBJECTIVE

This study investigated the effect of PRP in an I/R rat model 1 month after detorsion.

STUDY DESIGN

Of 24 adult male Sprague-Dawley rats, 18 were randomly assigned into three groups, with six in each: control, I/R and I/R + PRP. The PRP was prepared from the remaining six. Each group underwent right orchiectomy. Ischemia was performed by rotating the left testis 720° and fixing with a nylon suture for 4 h. Reperfusion occurred 4 h later by removing the suture, and PRP was administered at a dose of 10 μl (2000 × 10⁹/l) into the left testis via the intraparenchymal route. Animals were sacrificed at the fourth week, and testes were taken for malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), myeloperoxidase (MPO), transforming growth factor β (TGF-β), and caspase-3 measurements.

RESULTS

Ischemia/reperfusion caused a significant increase in MDA, MPO and caspase-3 activity, and significant decrease in GSH levels and SOD activity. The PRP treatment helped correct the alterations in SOD, caspase-3, and MPO activities and MDA levels. However, the mean MDA level and MPO activity were not totally restored compared with the controls. Serum testosterone levels of the I/R group were significantly lower compared with the control and I/R + PRP groups. TGF-β and caspase-3 protein expressions were significantly higher in the I/R group compared with the control group and were low with PRP administration compared with I/R groups (summary Table).

DISCUSSION

The findings of the present study suggest that PRP, by inhibiting neutrophil infiltration and oxidative stress and increasing antioxidant defense, exerts protective effects on testicular tissues against I/R. This study had some limitations: a scoring system was not used in the assessment of spermatogenesis in the histopathological findings and specific testis cell types were not histologically assessed.

CONCLUSIONS

In light of the biochemical, histological and, especially, hormonal findings, intraparenchymal PRP injection may have a protective effect in testicular tissue against I/R injury.

Ischemia/Reperfusion Injury following Acute Myocardial Infarction: A Critical Issue for Clinicians and Forensic Pathologists

Acute myocardial infarction (AMI) is a leading cause of morbidity and mortality. Reperfusion strategies are the current standard therapy for AMI. However, they may result in paradoxical cardiomyocyte dysfunction, known as ischemic reperfusion injury (IRI). Different forms of IRI are recognized, of which only the first two are reversible: reperfusion-induced arrhythmias, myocardial stunning, microvascular obstruction, and lethal myocardial reperfusion injury. Sudden death is the most common pattern for ischemia-induced lethal ventricular arrhythmias during AMI. The exact mechanisms of IRI are not fully known. Molecular, cellular, and tissue alterations such as cell death, inflammation, neurohumoral activation, and oxidative stress are considered to be of paramount importance in IRI. However, comprehension of the exact pathophysiological mechanisms remains a challenge for clinicians. Furthermore, myocardial IRI is a critical issue also for forensic pathologists since sudden death may occur despite timely reperfusion following AMI, that is one of the most frequently litigated areas of cardiology practice. In this paper we explore the literature regarding the pathophysiology of myocardial IRI, focusing on the possible role of the calpain system, oxidative-nitrosative stress, and matrix metalloproteinases and aiming to foster knowledge of IRI pathophysiology also in terms of medicolegal understanding of sudden deaths following AMI.

A Plasma-Based, Amiodarone-Impregnated Material Decreases Susceptibility to Atrial Fibrillation in a Post-Cardiac Surgery Model

OBJECTIVE

This study aimed to test the impact of a plasma-based, material (PBM) impregnated with amiodarone on atrial electrophysiology and atrial fibrillation susceptibility in a porcine post-cardiac surgery model.

METHODS

Ten healthy pigs underwent implantation of transvenous pacing systems, after which sterile talc was infused into the pericardial sac via a pericardiotomy. In five animals, PBM was applied to the atrial epicardial surface just before talc infusion. Electrophysiologic evaluations were performed using the pacing system immediately after chest closure and 7 days later. Atrial histologic evaluations were performed.

RESULTS

Immediately after chest closure, there were no significant differences in electrophysiologic parameters between talc-only and talc + PBM animals, and atrial fibrillation was largely noninducible. On postsurgical day 7, electrophysiologic evaluation revealed significantly shorter sinus cycle length and atrioventricular nodal refractoriness among talc-only animals relative to talc + PBM animals, possibly suggesting attenuated sympathetic nervous system activation in the latter. Atrial fibrillation inducibility and duration were significantly greater among talc-only animals. No significant differences in atrial refractoriness or conduction time between groups were apparent. Histologic evaluation revealed a relative reduction in epicardial inflammation and less myolysis among talc + PBM animals.

CONCLUSIONS

Epicardial application of a plasma-based, amiodarone-impregnated material was associated with a significant reduction in atrial inflammation and susceptibility to fibrillation.

Treatment of dilated cardiomyopathy in rabbits with mesenchymal stem cell transplantation and platelet-rich plasma

Dilated cardiomyopathy (DCM) is a major cause of cardiovascular mortality and morbidity, and there is evidence to suggest that stem cell transplantation may be a viable treatment option for this condition. Therefore, the goal of the present study was to assess myocardial regeneration in rabbits with doxorubicin-induced DCM treated with adipose mesenchymal stem cells (MSC) alone or in combination with platelet-rich plasma (PRP). Twenty New Zealand rabbits received doxorubicin for the induction of DCM and were divided into four groups according to treatment: saline, MSC, PRP and MSC + RP. Treatment agents were injected directly into the left ventricular myocardium following a thoracoscopy. Rabbits were assessed through echocardiographic and electrocardiographic examinations, as well as serum cardiac troponin I measurements at baseline, after the induction of DCM and 15 days after treatment. Animals were euthanased following the last assessment, and hearts were collected for histopathological analyses. The MSC group showed improvements in all parameters assessed, while the PRP group showed significantly impaired heart function. Histopathology of the heart revealed that the MSC group displayed the lowest number of lesions, while rabbits in the MSC + PRP, saline and PRP groups had steadily advancing lesions. These results suggest that MSC transplantation can improve heart function in rabbits with DCM, and underscore the need for further studies of the effects of PRP on the myocardium.

Role of platelet-rich plasma in ischemic heart disease: An update on the latest evidence

Myocardial infarction is the most common cause of congestive heart failure. Novel strategies such as directly reprogramming cardiac fibroblasts into cardiomyocytes are an exciting area of investigation for repair of injured myocardial tissue. The ultimate goal is to rebuild functional myocardium by transplanting exogenous stem cells or by activating native stem cells to induce endogenous repair. Cell-based myocardial restoration, however, has not penetrated broad clinical practice yet. Platelet-rich plasma, an autologous fractionation of whole blood containing high concentrations of growth factors, has been shown to safely and effectively enhance healing and angiogenesis primarily by reparative cell signaling. In this review, we collected all recent advances in novel therapies as well as experimental evidence demonstrating the role of platelet-rich plasma in ischemic heart disease, focusing on aspects that might be important for future successful clinical application.

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.

Factor XIII-A dynamics in acute myocardial infarction: a novel prognostic biomarker?

After acute myocardial infarction (MI) the damaged heart has to be repaired. Factor XIII (FXIII) is considered a key molecule in promoting heart healing. FXIII deficiency was associated to cardiac rupture and anomalous remodelling in MI. During MI, FXIII contributes firstly to the intracoronary thrombus formation and shortly after to heal the myocardial lesion. To quantify the real contribution of FXIII in this process, and to explore its possible prognostic role, we monitored the FXIII-A subunit levels in 350 acute MI patients during the first six days (d0-d5) plus a control at 30-60 days (d30). A one-year follow-up was performed for all the patients. A transient drop in the FXIII-A mean level was noted in the whole cohort of patients (FXIII-Ad0 99.48 ± 30.5 vs FXIII-Ad5 76.51 ± 27.02; p< 0.0001). Interestingly, those who developed post-MI heart failure showed the highest drop (FXIII-Ad5 52.1 ± 25.2) and they already presented with low levels at recruitment. Similarly, those who died showed the same FXIII-A dynamic (FXIII-Ad5 54.0 ± 22.5). Conversely, patients who remained free of major adverse cardiac events, had lower consuming (FXIII-Ad0 103.6 ± 29.1 vs FXIII-Ad5 84.4 ± 24.5; p< 0.0001). Interestingly, the FXIII-A drop was independent from the amount of injury assessed by TnT and CKMB levels. The survival analysis ascribed an increased probability of early death or heart failure inversely related to FXIII-A quartiles (FXIII-A25th< 59.5 %; hazard ratio 4.25; 2.2-5.1; p< 0.0001). Different FXIII-A dynamics and levels could be utilised as early prognostic indicators during acute MI, revealing the individual potential to heal and suggesting tailored treatments to avoid heart failure or its extreme consequence.

Efficacy of platelet-rich plasma for chronic tennis elbow: a double-blind, prospective, multicenter, randomized controlled trial of 230 patients

BACKGROUND

Elbow tenderness and pain with resisted wrist extension are common manifestations of lateral epicondylar tendinopathy, also known as tennis elbow. Previous studies have suggested platelet-rich plasma (PRP) to be a safe and effective therapy for tennis elbow.

PURPOSE

To evaluate the clinical value of tendon needling with PRP in patients with chronic tennis elbow compared with an active control group.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 2.

METHODS

A total of 230 patients with chronic lateral epicondylar tendinopathy were treated at 12 centers over 5 years. All patients had at least 3 months of symptoms and had failed conventional therapy. There were no differences in patients randomized to receive PRP (n = 116) or active controls (n = 114). The PRP was prepared from venous whole blood at the point of care and contained both concentrated platelets and leukocytes. After receiving a local anesthetic, all patients had their extensor tendons needled with or without PRP. Patients and investigators remained blinded to the treatment group throughout the study. A successful outcome was defined as 25% or greater improvement on the visual analog scale for pain.

RESULTS

Patient outcomes were followed for up to 24 weeks. At 12 weeks (n = 192), the PRP-treated patients reported an improvement of 55.1% in their pain scores compared with 47.4% in the active control group (P = .163). At 24 weeks (n = 119), the PRP-treated patients reported an improvement of 71.5% in their pain scores compared with 56.1% in the control group (P = .019). The percentage of patients reporting significant elbow tenderness at 12 weeks was 37.4% in the PRP group versus 48.4% in the control group (P = .143). Success rates for patients at 12 weeks were 75.2% in the PRP group versus 65.9% in the control group (P = .104). At 24 weeks, 29.1% of the PRP-treated patients reported significant elbow tenderness versus 54.0% in the control group (P = .009). Success rates for patients with 24 weeks of follow-up were 83.9% in the PRP group compared with 68.3% in the control group (P = .037). No significant complications occurred in either group.

CONCLUSION

No significant differences were found at 12 weeks in this study. At 24 weeks, however, clinically meaningful improvements were found in patients treated with leukocyte-enriched PRP compared with an active control group.

A novel hypothesis: the application of platelet-rich plasma can promote the clinical healing of white-white meniscal tears

The white-white tears (meniscus lesion completely in the avascular zone) are without blood supply and theoretically cannot heal. Basal research has demonstrated that menisci are unquestionably important in load bearing, load redistribution, shock absorption, joint lubrication and the stabilization of the knee joint. It has been proven that partial or all-meniscusectomy results in an accelerated degeneration of cartilage and an increased rate of early osteoarthritis. Knee surgeons must face the difficult decision of removing or, if possible, retaining the meniscus; if it is possible to retain the meniscus, surgeons must address the difficulties of meniscal healing. Some preliminary approaches have progressed to improve meniscal healing. However, the problem of promoting meniscal healing in the avascular area has not yet been resolved. The demanding nature of the approach as well as its low utility and efficacy has impeded the progress of these enhancement techniques. Platelet-rich plasma (PRP) is a platelet concentration derived from autologous blood. In recent years, PRP has been used widely in preclinical and clinical applications for bone regeneration and wound healing. Therefore, we hypothesize that the application of platelet-rich plasma for white-white meniscal tears will be a simple and novel technique of high utility in knee surgery.

Intramyocardial injection of platelet gel promotes endogenous repair and augments cardiac function in rats with myocardial infarction

OBJECTIVES

This study sought to explore the therapeutic potential of platelet gel for the treatment of myocardial infarction.

BACKGROUND

Cardiac dysfunction after acute myocardial infarction is a major cause of heart failure. Current therapy relies on prompt reperfusion and blockage of secondary maladaptive pathways by small molecules. Platelet gels are biomaterials rich in cytokines and growth factors, which can be manufactured in an autologous manner and are effective in various models of wound healing. However, the potential utility of platelet gel in cardiac regeneration has yet to be tested.

METHODS

Platelet gel was derived from syngeneic rats and its morphology, biocompatibility, secretion of beneficial factors, and in vivo degradation profile were characterized.

RESULTS

After delivery into infarcted rat hearts, the gel was efficiently infiltrated by cardiomyocytes and endothelial cells. Gel-treated hearts exhibited enhanced tissue protection, greater recruitment of endogenous regeneration, higher capillary density, and less compensatory myocyte hypertrophy. The cardiac function of control-injected animals deteriorated over the 6-week time course, while that of platelet gel-injected animals did not. In addition, the gel did not exacerbate inflammation in the heart.

CONCLUSIONS

Intramyocardial injection of autologous platelet gel ameliorated cardiac dysfunction after myocardial infarction. The striking functional benefits, the simplicity of manufacturing, and the potentially autologous nature of this biomaterial provide impetus for further translation.

Platelet-rich plasma peptides: key for regeneration

Platelet-derived Growth Factors (GFs) are biologically active peptides that enhance tissue repair mechanisms such as angiogenesis, extracellular matrix remodeling, and cellular effects as stem cells recruitment, chemotaxis, cell proliferation, and differentiation. Platelet-rich plasma (PRP) is used in a variety of clinical applications, based on the premise that higher GF content should promote better healing. Platelet derivatives represent a promising therapeutic modality, offering opportunities for treatment of wounds, ulcers, soft-tissue injuries, and various other applications in cell therapy. PRP can be combined with cell-based therapies such as adipose-derived stem cells, regenerative cell therapy, and transfer factors therapy. This paper describes the biological background of the platelet-derived substances and their potential use in regenerative medicine.