Platelet-poor Plasma Group Research Articles

Platelet-Poor vs Platelet-Rich Plasma For The Treatment Of Acute Thigh Muscle Injuries.

The aim of this study was to determine whether patients treated with platelet-poor plasma (PPP) after an acute thigh muscle injury would have a faster return to activity compared to patients treated with platelet-rich plasma (PRP). This quasi-experimental study included 100 patients (ages 16-45) with an acute thigh muscle injury diagnosed by sports ultrasound and treated with either PRP or PPP followed by a course of structured rehabilitation. The primary outcome was the number of days until unrestricted participation in sport, while the secondary outcome was the rate of recurrent injury within 12 months. The time until full, unrestricted participation in sport was significantly lower in the PPP group compared to the PRP group for all injury grades, with patients in the PPP group on average returning to unrestricted participation in sport 22.89 days more quickly than the PRP group (p < 0.001). Additionally, no significant difference in recurrent injury up to 12 months post-procedure was seen between groups (p = 0.967). PPP resulted in faster return to sport than PRP for acute thigh muscle injuries with a non-inferior injury recurrence rate. These findings suggest that future high level studies comparing PPP and PRP for the treatment of thigh muscle injuries should be considered.

THE EFFECT OF PLATELET-RICH PLASMA ADMINISTRATION ON PROLIFERATION AND DIFFERENTIATION OF ENDOTHELIAL PROGENITOR CELLS IN PATIENTS WITH STABLE CORONARY HEART DISEASE

Endothelial Progenitor Cells (EPCs) are crucial precursors to endothelial cells, playing a key role in regulating blood vessel structure and maintaining homeostasis to protect against inflammation and thrombosis, contributing to stable coronary heart disease (CHD). Growth factors stimulate signal transduction during EPC proliferation and differentiation. Platelet-Rich Plasma (PRP) contains widely recognized growth factors in angiogenesis. Our research aimed to analyze PRP's effects on EPC proliferation and differentiation in stable CHD patients. Using an experimental post-test control group design, mononuclear cells (MNCs) from peripheral blood were cultured with M-199 medium, divided into PRP, Platelet Poor Plasma (PPP), and control groups, and incubated for 14 days. EPC proliferation was quantified with CD34 markers using ANOVA. After 7 days, differentiated cells were counted with von Willebrand Factor (vWF) markers using the Mann-Whitney U test.EPC proliferation significantly increased in the PRP group (1.052 ± 0.16) compared to PPP (0.762 ± 0.19) and the control (0.068 ± 0.05, p=0.000). However, EPC differentiation showed no significant increase in the PRP group compared to PPP (0.00-0.30 vs. 0.00-0.20, p = 0.565) or the control (0.00-0.30 vs. 0.00-0.00, p = 0.064). Additionally, no significant increase in EPC differentiation was observed in the PPP group compared to the control (0.00-0.20 vs. 0.00-0.00, p = 0.144). PRP significantly enhanced EPC proliferation but did not significantly enhance differentiation in the peripheral blood of stable CHD patients compared to PPP and control groups.

Early treatment with Fibrinogen γ-chain peptide-coated, ADP-encapsulated Liposomes (H12-(ADP)-liposomes) ameliorates post-partum hemorrhage with coagulopathy caused by amniotic fluid embolism in rabbits

Amniotic fluid embolism is an unpredictable and sometimes lethal complication of childbirth. Fibrinogen γ-chain peptide-coated, ADP-encapsulated Liposomes (H12-(ADP)-liposomes), which were developed as a platelet substitute, may be useful to control postpartum hemorrhage with consumptive coagulopathy. This study aimed to establish a hemodynamically stable amniotic fluid embolism animal model and evaluate the efficacy of H12-ADP-liposome infusion in the initial management of postpartum hemorrhage complicated with amniotic fluid embolism-involved coagulopathy. Pregnant New Zealand white rabbits (28th day of pregnancy or normal gestation period of 29-35 days) underwent cesarean delivery, followed by intravenous administration of amniotic fluid (a total of 3.0 mL administered in 4 doses over 9 minutes). Thereafter, uncontrolled postpartum hemorrhage was induced by transecting the right midartery and concomitant vein in the myometrium. After initial bleeding for 5 minutes, rabbits received isovolemic fluid resuscitation through the femoral vein with an equivalent volume of blood loss every 5 minutes for 60 minutes. The transfusion regimens included platelet-rich plasma, platelet-poor plasma, and a bolus administration of H12-ADP-liposomes followed by platelet-poor plasma transfusion (8 rabbits per group). Moreover, 60 minutes after initiation of bleeding, rabbits received surgical hemostasis by ligation of bleeding vessels, except in cases with spontaneous hemostasis. The administration of amniotic fluid caused thrombocytopenia (56±3 × 103/μL) and prolonged both clotting time (before administration: 130.0±3.0 to 171.0±5.0 seconds) and prothrombin time (4.5±0.1 to 4.7±0.1 seconds). After the initial 5-minute bleeding in the rabbits, the mean arterial pressure fell to 43±2 mm Hg. Platelet-poor plasma transfusion alone further prolonged clotting time and prothrombin time at 60 minutes (192.0±10.0 and 5.2±0.1 seconds, respectively) with decreasing mean arterial pressure to <40 mm Hg. By contrast, the administration of H12-ADP-liposomes followed by platelet-poor plasma transfusion reduced the prolonged clotting time (153.0±5.0 seconds) and prothrombin time (4.9±0.1 seconds) similar to platelet-rich plasma transfusion (154.0±11.0 and 4.9±0.1 seconds, respectively) at 60 minutes. These rabbits maintained a mean arterial pressure of >45 mm Hg throughout the experiment. H12-ADP-liposome infusion and platelet-poor plasma transfusion and platelet-rich plasma transfusion yielded spontaneous hemostasis in 4 of 8 rabbits, whereas platelet-poor plasma transfusion did not stop bleeding in any of the rabbits. The total blood loss was 59±17 mL in the H12-ADP-liposomes and platelet-poor plasma group, which was half of that in the platelet-poor plasma group (124±10 mL). H12-ADP-liposome infusion may be effective in the initial management of postpartum hemorrhage complicated with amniotic fluid embolism, resulting in mitigation of consumptive coagulopathy.

Use of platelet lysate for in-vitro embryo production and treatment of repeat breeding in cows

Platelet-rich plasma (PRP) is a biological hemocomponent derived from blood after the complete removal of red blood cells and the partial or complete removal of white blood cells to concentrate platelets in an appropriate volume of plasma. Platelets have important growth factors, cytokines, and active metabolites that improve the endometrial environment and positively affect implantation. This study evaluated the effect of the addition of activated PRP (platelets lysate; PL) on in vitro bovine oocyte maturation and embryonic development and the effect of intrauterine (IU) infusion of autologous PL in repeat breeder (RB) cows. Experiment 1 examined the effects of allogeneic PL, fetal calf serum (FCS), mixed PL + FCS, or platelet-poor plasma (PPP) supplementations to in vitro maturation and development media on in vitro oocyte maturation and embryo development in good- and poor-quality oocytes of Japanese Black cows. Experiment 2 examined the IU infusion of autologous PL, 24 h post-insemination, in 21 RB Holstein-Friesian dairy cows. The cleavage rate of good-quality oocytes was higher in the PL group (85.93 ± 2.50%) than in the PPP group (67.16 ± 3.41%) (P < 0.05), while the cleavage rate of the poor-quality oocytes was higher in the PL alone (76.13 ± 4.04%) and mixed PL + FCS treated (73.59 ± 4.22%) groups than in the PPP group (54.64 ± 2.93%) (P < 0.05). The blastocyst rate of the good-quality oocytes was higher in the PL group (40.97 ± 3.03%) than in the FCS (27.97 ± 3.31%) and PPP (25.33 ± 2.15%) groups (P < 0.05). The blastocyst rate of poor-quality oocytes and the hatching rates of both good and poor-quality oocytes showed no significant differences among all groups. The conception rate in the autologous PL-treated group was 41.67% (5/12), while it was 11.11% (1/9) in the control group. The platelets' count in the pregnant PL-treated cows (n = 5; mean ± SEM, 1.07 ± 0.10 × 109/mL) was higher than in the non-pregnant ones (n = 7; 0.67 ± 0.10 × 109/mL) (P < 0.05). In conclusion, allogeneic PL was effective in stimulating the in vitro oocyte maturation and embryonic development in both good and poor-quality bovine oocytes, and post-insemination IU infusion of autologous PL derived from high platelets’ count-PRP would be recommended for the treatment of RB cows.

Perilesional injections of human platelet lysate versus platelet poor plasma for the treatment of diabetic foot ulcers: A double-blinded prospective clinical trial.

Diabetic foot ulcer (DFU) is a major cause of morbidity, non-traumatic lower limb amputation in diabetic patients and a high-cost burden on the healthcare system. New therapeutic products are increasingly tested. Platelet-rich plasma (PRP) and human platelet lysate (hPL) are reported to be useful. This trial was conducted to test whether the healing effect of hPL in chronic DFU was due to plasma or platelet lysates in a prospective double-blind design. Autologous PRP was obtained from citrated blood, lysed, and used as drug 1 (active product). The platelet-poor plasma (PPP) was used as a drug 2 (placebo). Ten patients were enrolled in arm 1 and 9 in arm 2. The drugs were injected perilesionally every 2 weeks for a total of sixinjections. Adverse events were recorded until Week 14. The DFUs were scored per the Texas and Wegner systems. No patient showed any major adverse events. Some reported local pain post-injection. Wound healing was achieved in the hPL group in 9/10 of patients at a mean of 35.1 days. In the PPP group, no patient had healed by Day 84. The difference was statistically significant at P < 0.00001. We conclude that autologous hPL is safe and highly effective in healing chronic DFU and is superior to autologous PPP.

Autologous Fibrin Sealants Have Comparable Graft Fixation to an Allogeneic Sealant in a Biomechanical Cadaveric Model of Chondral Defect Repair

PurposeThe purpose of this study is to assess the integrity of chondral defect repairs filled with a cartilage allograft and sealed with either allogeneic fibrin sealant or autologous fibrin sealants created with platelet-rich plasma (PRP) or platelet-poor plasma (PPP) in a cadaver model.MethodsTwenty-millimeter medial femoral condyle (MFC) chondral defects were created in five human cadaveric knees. The defects were filled with particulated cartilage allograft hydrated with PRP from human donors until slightly recessed. Sealants were applied until flush with the articular surface using PRP and autologous thrombin serum, PPP and autologous thrombin serum, or commercial allogeneic sealant. The MFC defects were cycled using a multiaxial testing system to simulate continuous passive motion undergone during rehabilitation. After testing, the repairs were assessed for integrity by quantitatively comparing defect exposure and qualitatively assessing sealant delamination.ResultsThe mean defect exposures were 4.20% ± 5.02% for the PRP group, 4.60% ± 5.18% for the PPP group, and 1.80% ± 2.95% for the allogeneic sealant group. No significant differences were observed between groups (P = .227), and each group had significantly less defect exposure when compared to the critical clinically relevant value assigned to be 30% (P = <.001 for all). No complete sealant delamination was observed, although the allogeneic sealant delaminated with a higher magnitude than did the autologous sealants.ConclusionsThe PRP and PPP sealants were comparable to the allogeneic sealant for graft fixation when used in conjunction with an underlying PRP-hydrated particulated cartilage allograft. The autologous sealants had better delamination resistance than the allogeneic sealant.Clinical RelevanceThe time-zero model is critical in elucidating the retention properties of fibrin and allogenic sealants after cartilage repair and before healing processes help stabilize the repair.

H12‐(ADP)‐liposomes for hemorrhagic shock in thrombocytopenia: Mesenteric artery injury model in rabbits

BackgroundDamage control resuscitation improves patient outcomes after severe hemorrhage and coagulopathy. However, effective hemostasis methods for these critical situations are lacking. ObjectiveWe evaluated the hemostatic efficacy of fibrinogen γ‐chain (HHLGGAKQAGDV, H12)‐coated, adenosine‐diphosphate (ADP)‐encapsulated liposomes (H12‐[ADP]‐liposomes) in thrombocytopenic rabbits with hemorrhagic shock. MethodsAcute thrombocytopenia (80%) was induced in rabbits that also received mesenteric vessel injury, leading to hemorrhagic shock. Five minutes after injury, subjects received intravenous bolus injection with H12‐(ADP)‐liposomes (20 mg/kg), followed by isovolemic transfusion with stored red blood cells (RBCs)/platelet poor plasma (PPP) (RBC:PPP = 1:1 [vol/vol]), or lactated Ringer solution every 5 min to compensate blood loss. One group received H12‐(phosphate buffered saline [PBS]) liposomes followed by RBC/PPP. Additional groups were received isovolemic transfusion with RBC/platelet rich plasma (PRP) (RBC:PRP = 1:1 [vol/vol]), RBC/PPP, PPP alone, or lactated Ringer solution. ResultsTreatment with H12‐(ADP)‐liposomes followed by RBC/PPP transfusion and RBC/PRP transfusion effectively stopped bleeding in all thrombocytopenic rabbits. In contrast, three of 10 rabbits treated with RBC/PPP failed hemostasis, and no rabbits receiving lactated Ringer solution stopped bleeding or survived. Twenty‐four hours after hemorrhage, 80% of rabbits receiving H12‐(ADP)‐liposome followed by RBC/PPP transfusion survived and 70% of rabbits receiving RBC/PRP transfusion also survived, although RBC/PPP‐transfused rabbits showed 40% survival. Rabbits receiving H12‐(ADP)‐liposomes followed by lactated Ringer solution showed a transient hemostatic potential but failed to survive. H12‐(PBS)‐liposomes showed no beneficial effect on hemostasis. Neither the PPP group nor the lactated Ringer group survived. ConclusionH12‐(ADP)‐liposome treatment followed by RBC/PPP may be effective in lethal hemorrhage after mesenteric vessel injury in coagulopathic rabbits.

A Histological Study on Platelet Poor Plasma versus Platelet Rich Plasma in Amelioration of Induced Diabetic Neuropathy in Rats and the Potential Role of Telocyte-like Cells

Background: Diabetic neuropathy (DN) is a major chronic diabetes complication characterized by functional and structural alterations in peripheral nerves. Platelet rich plasma (PRP) is an encouraged biological blood derivative that has gained publicity in diverse applications and proved its efficacy.Aim of Work: Evaluate the probable ameliorating effect of platelet poor plasma (PPP) versus PRP on induced DN in rats.Materials and Methods: This study included 48 male adult albino rats, 10 to obtain PRP and PPP. Thirty eight were divided into 4 groups; group I (control). Group II (DN group): received a single intraperitoneal STZ (60 mg/kg) injection and were left till the end of the experiment. Groups III (PRP group) and IV (PPP group) received subcutaneous PRP or PPP 0.5 mL/kg, 2 times a week for 3 weeks after 60 days diabetes. Body weight, blood glucose and miR-146a and nerve conduction velocity (NCV) were assessed, as well as tissue MDA, TNFα, NGF, ZO-1 and claudin-1. Right sciatic nerve specimens were taken and processed for HandE, toluidine blue stains, S100, CD34 and caspase-3 immunohistochemical stains and TEM. Number of CD34 immunopositive cells and area percent of S100 and caspase-3 immunoreaction were measured, in addition to G-ratio and capillary luminal area. This was followed by statistical analysis.Results: DN group showed altered biochemical and histological features; axonopathy, Schwannopathy and angiopathy, with affected NCV and telocyte-like cells (TLCs). PRP and PPP groups showed comparable results to each other and to the control. They revealed almost normal biochemical and histological features and NCV. In addition, they revealed significant increase in S100 and CD34 immunoexpression with significant decrease in area percent of caspase-3 versus DN group.Conclusion: PPP and PRP proved to exert ameliorative effect on DN through improving the biochemical and histopathological altera‌tions and TLCs preservation.

Effect of platelet-rich and platelet-poor plasma on peri-implant innervation in dog mandibles

BackgroundAutologous plasma fractions, such as platelet-rich plasma (PRP) and platelet-poor plasma (PPP), contain growth factors that can enhance neural cell survival and are therefore likely to have the ability to promote nerve regeneration. The present study compared the effect of PRP and PPP application on myelinated nerve density and diameter in the peri-implant bone region. In addition, the effect of healing time on nerve regeneration was assessed.Materials and methodsNine beagle dogs randomly received 54 dental implants in the bilateral mandible according to a split-mouth design. Each implant was randomly assigned to one of three implant protocols: delayed implant placement with delayed loading (DIP + DL) with local application of PRP, DIP + DL with local application of PPP and DIP + DL without any plasma additive. The animals were euthanized at 1, 3, and 6 months after loading (3 dogs per time point). Block biopsies were prepared for histomorphometry in the peri-implant bone within 500 μm around the implants.ResultsMyelinated nerve fibers were identified in the trabecular bone and in the osteons near the implants surface. The nerve fibers in the PRP group (median ± IQR; 2.88 ± 1.55 μm) had a significantly (p < 0.05) greater diameter compared to the PPP (2.40 ± 0.91 μm) and control (2.11 ± 1.16 μm) group. The nerve diameter after 6 months healing (3.18 ± 1.58 μm) was significantly (p < 0.05) greater compared to 1 (2.08 ± 0.89 μm) and 3 (2.49 ± 1.22 μm) months. No significant difference was found for myelinated nerve density between groups and healing time.ConclusionsThe present study showed that the healing time significantly influenced the diameter of the myelinated nerve fibers in peri-implant bone. PRP exerted a significant effect on the diameter of the myelinated nerve fibers as compared to PPP. Large-scale animal studies and longer follow-up periods are needed to confirm these findings and to verify whether platelet plasma can facilitate nerve regeneration process.

Effect of platelet-rich plasma on peri-implant trabecular bone volume and architecture: A preclinical micro-CT study in beagle dogs.

To evaluate the peri-implant trabecular bone volume and architecture changes with 6-month follow-up after local application of platelet-rich plasma (PRP) and platelet-poor plasma (PPP) using high-resolution micro-CT. Seventy-two dental implants were placed into healed mandibular sites of 9 beagle dogs. Implants were randomly divided into 4 groups following a split-mouth design: control I; control II; PPP; and PRP. Primary and secondary stabilities were assessed using resonance frequency analyses. At 1, 3, and 6months after implant loading, trabecular structural parameters were evaluated at 0.5, 1, and 1.5mm away from implants using micro-CT (voxel=20μm). Primary and secondary stabilities were equivalent in all conditions. PPP and PRP groups showed higher bone volume fraction (BV/TV) and trabecular thickness (Tb.Th) but lower trabecular separation (Tb.Sp) and total porosity percentage (Po (tot)) at all 3 time points. A significant decrease in BV/TV and Tb.Th was found for the control groups after 3months of healing, while this was not observed in both the PPP and PRP groups. However, no distinct difference was found between the PRP and PPP groups over time. Moreover, as the investigated distance from the implant surface increased, BV/TV and Po (tot) within the same group and time point stayed the same, yet Tb.Th and Tb.Sp continued to increase. Platelet-rich plasma and PPP with conventional implant placement lead to similar primary and secondary implant stability, but improved peri-implant bone volume and structural integration. The present research does not seem to suggest a different bone remodeling pattern when using PRP or PPP.

EFFECT OF PLATELET RICH PLASMA ON PROLIFERATION OF ENDOTHELIAL PROGENITOR CELL (EPC) OF STABLE CORONARY ARTERY DISEASE PATIENT

ABSTRACT&#x0D; Effect of Platelet Rich Plasma (PRP) on Proliferation of Endothelial Progenitor Cell (EPC) of Stable Coronary Artery Disease Patient&#x0D; Ronald R Hehanusa, Andrianto, Budi S Pikir&#x0D; &#x0D; Background : Endothelial Progenitor Cell (EPC) is the progenitor of endothelial cell which has important role in regulation of vascular wall integrity and homeostasis, to protect vessels from inflamation and thrombosis, that leads into pathogenesis of coronary artery disease. Growth factors proven has important role to stimulate transduction signal in the process of proliferation of EPC. Platelet Rich Plasma (PRP) contains variety of growth factors, wellknown role in homeostasis and wound healing process. Therefore, this study was conducted to analyze the effect of PRP on proliferation of EPC of Stable Coronary Artery Disease (SCAD) patient.&#x0D; Objective : To analyze the effect of Platelet Rich Plasma (PRP) on the proliferation of Endothelial Progenitor Cell (EPC) from peripheral blood of patient with SCAD &#x0D; Methods : This is an in vitro, true experimental, post-test only control group design. The mononuclear cells were isolated from peripheral blood of SCAD patient and cultured in M-199 medium. EPC divided into 3 groups, which received Platelet Rich Plasma (PRP), Platelet Poor Plasma (PPP), and control. After 14 days of incubation, immunocytochemical examination was performed, EPC which marked with CD34, FITC labeled,was counted using immunofluoroscence microscope. Data analysis using ANOVA test.&#x0D; Result : Cell counting showed significant increase of EPC proliferation in PRP group compared to PPP group (1.052 ± 0.16 vs 0.762 ± 0.19, p = 0.003), and control group as well (1.052 ± 0.16 vs 0.068 ± 0.05, p = 0.000). EPC proliferation in PPP group also increase significantly compared to control group (0.762 ± 0.19 vs 0.068 ± 0.05, p = 0.000).&#x0D; Conclusion : Platelet Rich Plasma (PRP) increase EPC proliferation significantly from peripheral blood of SCAD patient.&#x0D; &#x0D; Keywords : EPC proliferation, PRP, SCAD

Clinical effects of platelet rich fibrin in prevention of bleeding and swelling after mandibular angle reduction

Objective To observe the clinical effect of platelet- rich fibrin (PRF) on prevention of postoperative hemorrhage and facial traumatic swelling in patients with mandibular angle osteotomy. Methods Twenty-five patients with mandibular angle hypertrophy were included in this study from January 2014 to November 2015. Split face comparative study was carried out to use the left and right sides as the experimental side and the control side, respectively. The PRF in the experimental side was placed in the mandibular osteotomy, while the control side was placed in platelet- poor plasma (PPP). After operation, the drainage volume and facial swelling degree were measured. Results The drainage volume of the experimental group (PRF group) was (20.35±7.40) ml, the control group (PPP group) was (43.23±11.96) ml, and the difference was statistically significant (P<0.05). There was no such case without swelling in postoperative third day. The facial swelling score on the experimental side was (1.19±0.40), the control side was (2.62±0.64), and two groups of postoperative facial swelling scores were significantly different (P<0.05). Conclusions The PRF can reduce postoperative bleeding and facial swelling after mandibular angle osteotomy. Key words: Mandibular angle reduction; Platelet- rich fibrin; Postoperative hemorrhage; Facial traumatic swelling

Positive effect on spinal fusion by the combination of platelet-rich plasma and collagen-mineral scaffold using lumbar posterolateral fusion model in rats

BackgroundPlatelet-rich plasma (PRP) is autologous in origin and contains a high concentration of platelets which is a source of various growth factors. Previous studies have suggested that PRP has a positive effect in accelerating fusion by an autologous bone graft in a lumbar fusion. The role of PRP on artificial bone grafts in spinal fusion remains controversial. In this study, positive effect on spinal fusion by PRP was hypothesized; in vitro and in vivo studies were designed to test this hypothesis.MethodsPRP was produced from peripheral blood of Sprague-Dawley (SD) rats. A lumbar posterolateral arthrodesis model was used to test the efficacy of PRP on spinal fusion. Thirty SD rats were divided into three groups by different implants: the PRP group, PRP plus collagen-mineral carrier; the platelet-poor plasma (PPP) group, PPP plus collagen-mineral carrier; and the control group, collagen-mineral only. Spinal fusion was examined using plain radiographs, micro-computed tomography (micro-CT), manual palpation, and histological analysis. The fusion rate by micro-CT and that by manual palpation in groups were compared.ResultsIn the micro-CT results, 16 fused segments were observed in the PRP group (80%, 16/20), 2 in the PPP group (10%, 2/20), and 2 in the control group (10%, 2/20). The fusion rate, determined by manual palpation, was 60% (6/10) in the PRP group, 0% (0/10) in the PPP group, and 0% (0/10) in the control group. Histology showed that the PRP group had more new bone and matured marrow formation.ConclusionsThe results of this study demonstrated that PRP on an artificial bone carrier had positive effects on lumbar spinal fusion in rats. In the future, this composite could be potentially used as a bone graft in humans.

Efficacy of Resuscitative Transfusion With Hemoglobin Vesicles in the Treatment of Massive Hemorrhage in Rabbits With Thrombocytopenic Coagulopathy and Its Effect on Hemostasis by Platelet Transfusion.

We have developed hemoglobin vesicles (HbVs) as a substitute for red blood cells (RBCs). We investigated the efficacy of HbV transfusion in the treatment of massive hemorrhage in rabbits in the setting of thrombocytopenic coagulopathy, focusing on the efficacy of hemostasis by subsequent platelet transfusion. Thrombocytopenic coagulopathy was induced in rabbits by repeated blood withdrawal and isovolemic retransfusion of autologous RBC (platelet counts <45,000/μL). A penetrating liver injury was then made. For 30 min, bleeding volume was measured every 10 min, after which subjects were transfused with an equivalent volume of stored RBC, HbV, or platelet poor plasma (PPP) to compensate for blood loss, simulating initial prehospital resuscitation. Thereafter, we transfused platelet rich plasma (PRP) to stop bleeding, which simulated inhospital resuscitation. During the initial resuscitation, the HbV group was similar to the RBC group (but not the PPP group) in their hemodynamics and tissue circulation/oxygenation as assessed by plasma lactate levels. All rabbits showed similar bleeding volumes (20-30 mL) in this period. HbV-transfused rabbits sustained hemoglobin levels, but showed lower hematocrit levels compared with RBC-transfused rabbits. Subsequent PRP transfusion effectively stopped bleeding in all RBC-transfused rabbits (6/6) and most HbV-transfused rabbits (7/8) but not PPP-transfused rabbits (2/8). In addition, 83% of RBC-transfused rabbits and 75% of HbV-transfused rabbits survived for 24 h, although no PPP-transfused rabbits survived. HbV transfusion did not scavenge nitric oxide in rabbits. HbV transfusion effectively rescued rabbits from severe hemorrhage with coagulopathy, without disturbing hemostasis after the platelet transfusion. HbV transfusion may be practical and useful in prehospital resuscitation.

Platelet-rich Plasma Protects HUVECs against oX-LDL-induced Injury.

Platelet-rich plasma (PRP) contains a variety of cytokines, some of which ameliorate oX-LDL (oxidized low-density lipoprotein)-induced endothelial cell (EC) injury. Therefore, we hypothesized that PRP might alleviate oX-LDL-induced injury.MethodologyHuman umbilical vein endothelial cells (HUVECs) were divided into four groups: a PPP (platelet-poor plasma) group, an oX-LDL group, an oX-LDL+PRP group and a PRP group. CCK-8 (Cell Counting Kit) assay, Annexin V-FITC/7-AAD and Hochest 33342 staining were performed to assess cell proliferation and apoptosis. Tube formation and cell migration assays were performed to evaluate HUVEC-mediated vasculogenesis and migration. Expression levels of Bcl-2, Bax, caspase-3, cleaved caspase-3, PI3K, Akt, eNOS p-Akt, p-eNOS, IL-6 and IL-1 were detected by western blotting or immunofluorescence.Principal findingsPRP promoted HUVEC proliferation in a non-linear pattern, protected HUVECs against oX-LDL-induced apoptosis and attenuated oX-LDL-mediated inhibition of HUVEC migration and vasculogenesis. Additionally, compared to the PPP group, PRP downregulated pro-apoptotic proteins (ratio of Bax/Bcl-2, caspase-3 and cleaved caspase-3) as well as IL-6 and IL-1. Moreover, the PI3K/Akt/eNOS pathway was activated by PRP and inactivated by oX-LDL.ConclusionsIt was demonstrated that PRP protected HUVECs against oX-LDL-induced injury and that the PI3K/Akt/eNOS pathway was activated in this process.

Effects of Platelet-Poor Plasma, Platelet-Rich Plasma, and Platelet-Rich Fibrin on Healing of Extraction Sockets with Buccal Dehiscence in Dogs

Alveolar bone resorption generally occurs during healing after tooth extraction. This study aimed to evaluate the effects of platelet-poor plasma (PPP), platelet-rich plasma (PRP), and platelet-rich fibrin (PRF) on healing in a ridge-augmentation model of the canine socket with dehiscence of the buccal wall. The third mandibular premolars of 12 beagle dogs were extracted and a 3 mm buccal dehiscence from the alveolar crest to the buccal wall of the extraction socket was created. These sockets were then divided into four groups on the basis of the material used to fill the sockets: PPP, PRP, PRF, and control (no graft material) groups. Results were evaluated at 4 and 8 weeks after surgery. The ultrastructural morphology and constructs of each blood product were studied by a scanning electron microscope (SEM) or calculating concentrations of platelets, fibrinogen, platelet-derived growth factor, and transforming growth factor-β. A total of five microcomputed tomography images of specimens were selected for measurement, and the area occupied by the newly formed bone as well as the horizontal bone width were measured. Moreover, decalcified tissue specimens from each defect were analyzed histologically. The median area of new bone at 4 and 8 weeks and median horizontal bone width at 8 weeks were the highest in the PPP group. However, bone maturation in the PRF and the PRP groups was more progressed than that in the PPP and control groups. By SEM findings, the PRF group showed a more highly condensed fibrin fiber network that was regularly arranged when compared with the PPP and PRP groups. The growth factors released from platelets in PRP indicated higher concentrations than that in PRF. Under more severe conditions for bone formation, as in this experiment, the growth factors released from platelets had a negative effect on bone formation. This study showed that PPP is an effective material for the preservation of sockets with buccal dehiscence.

Increasing platelet concentration in platelet‐rich plasma inhibits anterior cruciate ligament cell function in three‐dimensional culture

Tissue engineering is one new strategy being developed to treat ACL ruptures. One such approach is bio-enhanced ACL repair, where a suture repair is supplemented with a bio-active scaffold containing platelets. However, the optimal concentration of platelets to stimulate ACL healing is not known. We hypothesized that increasing platelet concentrations in the scaffold would enhance critical cell behaviors. Porcine ACL fibroblasts were obtained from explant culture and suspended in platelet poor plasma (PPP), 1× platelet-rich plasma (PRP), 3× PRP, 5× PRP, or phosphate buffered saline (PBS). The cell suspensions were cultured in a 3D collagen scaffold. Cellular metabolism (MTT assay), apoptosis (TUNEL assay), and gene expression for type I and type III collagen were measured. 1× PRP significantly outperformed 5× PRP in all parameters studied: Type I and III collagen gene expression, apoptosis prevention, and cell metabolism stimulation. ACL fibroblasts cultured with 1× PRP had the highest type I and type III collagen gene expression. 1× PRP and PPP groups had the highest cell metabolism and lowest apoptosis rates. Concentration of platelets had significant effects on the behavior of ACL fibroblasts; thus, it is an important parameter that should be specified in clinical or basic science studies.

Autologous platelet-poor plasma decreases the bronchial stump necrosis in rat

BackgroundNecrosis of the bronchial stump is a very important trigger for bronchopleural fistula. The administration of local autologous platelet-poor plasma (PPP) could protect the bronchial stump. Materials and methodsLeft pneumonectomy was performed in 25 Sprague-Dawley rats. Animals were randomly assigned to a control group (n=13) and PPP group (n=12). PPP was locally administered on the bronchial stump after pneumonectomy. We analyzed histologic changes in the bronchial stump and messenger RNA expression changes of genes involved in wound repair at 10 and 20 d. ResultsLocal PPP treatment produced a mass of fibrous tissue surrounding the bronchial stump and significantly decreased the presence of necrosis at 20 d. PPP increased the expression of insulin like growth factor 1 at 10 d although it did not reach statistical significance. ConclusionsOur findings indicate that local PPP treatment of the bronchial stump after pneumonectomy decreased necrosis and could have a protective effect on the bronchial stump.

RapidlyIn SituForming Platelet-Rich Plasma Gel Enhances Angiogenic Responses and Augments Early Wound Healing after Open Abdomen

Objective. The purposes of our present study were to evaluate the potential of platelet-rich plasma gel to enhance granulation tissue formation after open abdomen and to examine whether the effect was attributable to stimulating rapid neovascularization. Methods. Twenty-four rats underwent colon ascendens stent peritonitis surgery to induce sepsis, followed by intraperitoneal injection of nitrogen to create intra-abdominal hypertension. Four hours later, laparotomies were performed. The rats were randomized into three groups (n = 8 for each group): control, platelet-poor plasma (PPP), and platelet-rich plasma (PRP) groups. One week after the treatment, granulation tissue formation and angiogenesis were evaluated by histological and laser Doppler analysis. Results. The resultant platelet count in platelet-rich plasma was higher than that of PPP. The concentrations of platelet-derived growth factor BB, transforming growth factor β-1, and vascular endothelial growth factor in PRP were significantly higher when compared with that of PPP. Myofibroblast count, granulation tissue thickness, vessel numbers, and blood perfusion were increased in PRP group, followed by PPP group, with control being the least. Conclusion. Rapidly in situ forming platelet-rich plasma gel promoted remarkable neovascularization and early wound healing after open abdomen and may lead to novel and effective treatments for open abdominal wounds.

Antibacterial Effect of Autologous Platelet-Rich Gel Derived from Subjects with Diabetic Dermal Ulcers In Vitro

Background. Autologous platelet-rich gel (APG) is an effective method to improve ulcer healing. However, the mechanisms are not clear. This study aimed to investigate the antibacterial effect of APG in vitro. Methods. Platelet-rich plasma (PRP), platelet-poor plasma (PPP) and APG were prepared from whole blood of sixteen diabetic patients with dermal ulcers. Antibacterial effects against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa were evaluated by bacteriostasis assay of APG, PRP, and APG-APO (APG combined with apocynin), with phosphate-buffered saline (PBS) and PPP as the control group. Results. (1) Compared to the PBS and PPP, the APG and APG-APO groups showed strong antibacterial activity against Staphylococcus aureus. There was no significant difference (P > 0.05) between APG and APG-APO. (2) Compared to PBS, APG, APG-APO, and PRP showed obvious antibacterial effects against Escherichia coli and Pseudomonas aeruginosa. No significant difference (P > 0.05) was revealed among the three groups. Compared to the PPP group, they did not show antibacterial effect against Escherichia coli and Pseudomonas aeruginosa (P > 0.05). Conclusions. APG has antibacterial effect against Staphylococcus aureus mediated by platelet activation in the diabetic patients with dermal ulcer, and does not present obvious antibacterial effect against Escherichia coli or Pseudomonas aeruginosa. Combination of APG and antibiotics may have synergistic antibacterial effect.