Plasma rich in growth factors promote gingival tissue regeneration by stimulating fibroblast proliferation and migration and by blocking transforming growth factor-β1-induced myodifferentiation

Evaluation of leukocyte-platelet rich fibrin as an antibiotic slow-release biological device in the treatment of moderate periodontitis: a randomized controlled clinical trial

BACKGROUND

Periodontitis is a chronic inflammatory disease caused by the accumulation of biofilm. Antimicrobials have been used as adjuncts to non-surgical periodontal therapy. However, systemic antibiotics often require large dosages to achieve suitable concentrations at the disease site. Leukocyte platelet-rich fibrin (L-PRF) is a promising bio-material, with antimicrobial, anti-inflammatory, and wound-healing enhancement effects. This study aimed to evaluate the efficacy of L-PRF as a locally sustained released device for metronidazole antimicrobial.

METHODS

Twenty-four patients with eighty periodontal pockets had moderate periodontitis with attachment loss of 3-4 mm, and probing depth ≤ 5, which was equally divided into two groups: Group (I) underwent scaling and root planing with intra-pocket application of L-PRF loaded with Metronidazole, while Group (II) was treated by scaling and root planing with intra-pocket application of L-PRF alone. Microbiological measurements were taken at baseline and after one month to analyze the relative count of Porphyromonas gingivalis (P. gingivalis) using real time PCR. Clinical parameters were measured at baseline and after 1, 3, and 6 months. These parameters included probing depth (PD), clinical attachment loss (CAL), plaque index (PI), modified gingival index (MGI), and bleeding index (BI).

RESULTS

Microbiological and clinical findings revealed that both treatment methods resulted in a reduction in P. gingivalis counts, in addition to improvements in the clinical parameters: PD reduction, CAL gain, PI reduction, BI decrease and MGI reduction compared to baseline. However, L-PRF-metronidazole group showed superior results in the studied parameters over the study period. Nonetheless, there was no statistically significant improvement. (p < .001).

CONCLUSION

The intra-pocket application of both L-PRF loaded with Metronidazole and L-PRF alone contributed to the successful treatment of moderate periodontitis.

TRIAL REGISTRATION

NCT06153706 ( http://www.clinical-trials.gov/ ); 1/12/2023, retrospective registration.

Decellularized extracellular matrix derived from dental pulp stem cells promotes gingival fibroblast adhesion and migration

BACKGROUND

Decellularized extracellular matrix (dECM) has been proposed as a useful source of biomimetic materials for regenerative medicine due to its biological properties that regulate cell behaviors. The present study aimed to investigate the influence of decellularized ECM derived from dental pulp stem cells (DPSCs) on gingival fibroblast (GF) cell behaviors. Cells were isolated from dental pulp and gingival tissues. ECM was derived from culturing dental pulp stem cells in growth medium supplemented with ascorbic acid. A bioinformatic database of the extracellular matrix was constructed using Metascape. GFs were reseeded onto dECM, and their adhesion, spreading, and organization were subsequently observed. The migration ability of the cells was determined using a scratch assay. Protein expression was evaluated using immunofluorescence staining.

RESULTS

Type 1 collagen and fibronectin were detected on the ECM and dECM derived from DPSCs. Negative phalloidin and nuclei were noted in the dECM. The proteomic database revealed enrichment of several proteins involved in ECM organization, ECM-receptor interaction, and focal adhesion. Compared with those on the controls, the GFs on the dECM exhibited more organized stress fibers. Furthermore, cultured GFs on dECM exhibited significantly enhanced migration and proliferation abilities. Interestingly, GFs seeded on dECM showed upregulation of FN1, ITGB3, and CTNNB1 mRNA levels.

CONCLUSIONS

ECM derived from DSPCs generates a crucial microenvironment for regulating GF adhesion, migration and proliferation. Therefore, decellularized ECM from DPSCs could serve as a matrix for oral tissue repair.

Platelet-Rich Plasma as a Novel, Non-invasive Method to Treat Breast Capsular Contractures: a Case Report

We describe the first examples of breast capsular contracture amelioration using a non-surgical, transdermal treatment with platelet-rich plasma. The treated patients did not experience any complications or significant pain. This report illustrates the potential of a non-invasive treatment option for a common complication of breast augmentation.

Cellular composition modifies the biological properties and stability of platelet rich plasma membranes for tissue engineering

Scaffolds should provide structural support for tissue regeneration, allowing their gradual biodegradation and interacting with cells and bioactive molecules to promote remodeling. Thus, the scaffold's intrinsic properties affect cellular processes involved in tissue regeneration, including migration, proliferation, differentiation, and protein synthesis. In this sense, due to its biological effect and clinical potential, Platelet Rich Plasma (PRP) fibrin could be considered a successful scaffold. Given the high variability in commercial PRPs formulations, this research focused on assessing the influence of cellular composition on fibrin membrane stability and remodeling cell activity. The stability and biological effect were evaluated at different time points via D-dimer, type I collagen and elastase quantification in culture media conditioned by Plasma Rich in Growth Factors - Fraction 1 (PRGF-F1), Plasma Rich in Growth Factors - Whole Plasma (PRGF-WP) and Leukocyte-rich Platelet Rich Plasma (L-PRP) membranes, and by gingival fibroblast cells seeded on them, respectively. Ultrastructure of PRP membranes was also evaluated. Histological analyses were performed after 5 and 18 days. Additionally, the effect of fibrin membranes on cell proliferation was determined. According to the results, L-PRP fibrin membranes degradation was complete at the end of the study, while PRGF membranes remained practically unchanged. Considering fibroblast behavior, PRGF membranes, in contrast to L-PRP ones, promoted extracellular matrix biosynthesis at the same time as fibrinolysis and enhanced cell proliferation. In conclusion, leukocytes in PRP fibrin membranes drastically reduce scaffold stability and induce behavioral changes in fibroblasts by reducing their proliferation rate and remodeling ability.

Comparison of Antimicrobial Activity of Injectable Platelet-Rich Fibrin (i-PRF) and Leukocyte and Platelet-Rich Fibrin (l-PRF) Against Oral Microbes: An In Vitro Study

Aim Injectable platelet-rich fibrin (i-PRF) and leukocyte and platelet-rich fibrin (l-PRF) are both blood-derived products used in regenerative medicine and dentistry. They contain platelets, growth factors, and leukocytes, which can have antimicrobial properties to some extent, but their primary purpose is tissue regeneration and wound healing. i-PRF and l-PRF may have some indirect antimicrobial properties due to their composition and ability to enhance tissue healing and immune responses, and they are primarily used in dentistry for their regenerative and wound healing capabilities rather than as standalone antimicrobial agents. This study aims to compare the anti-microbial activity of i-PRF and l-PRF against oral microbes. Methodology This study included 30 patients who were selected using G*Power software version 3.1 (Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany) calculation with the population size. The plaque samples were collected from the subjects using area-specific Gracey curettes used for scaling and root planing to remove plaque and calculus from the teeth and root surfaces. The collected plaque samples were transferred to a tube containing 5 ml of saline (sterile saltwater). The purpose of using saline is to preserve the microbial content of the plaque sample without altering the microbial composition. To obtain a uniform solution, the samples in the saline-containing tube were vortexed for 5 minutes. After vertexing, a small amount of the suspension (0.1 ml) was taken for further analysis. The 0.1 ml suspension was used to plate blood agar using the streak method. A loop or needle is used to streak the sample back and forth across the surface of the agar, leading to the dilution and separation of the bacteria. Results Results state that i-PRF has a maximum zone of inhibition (2.19±0.47 mm) when compared with metronidazole (0.14±0.09 mm). It can be stated that platelet concentrates demonstrate better antimicrobial activity due to their higher oxygen metabolites which help in the aggregation and internalization of microorganisms, which enhances the clearance of pathogens from the bloodstream. Paired t-test has been used for the comparison between the two groups, and the p-value is >0.05 stating that the difference is statistically significant. Conclusion The present study states that i-PRF demonstrated better antimicrobial efficacy as compared to l-PRF. Hence, i-PRF helps in reducing microbial load at the periodontally infected sites when compared with l-PRF.

Metal-organic framework-based nanoplatform enhance fibroblast activity to treat periodontitis

After periodontal tissue injury, reconstruct soft tissue sealing around the tooth surface is of fundamental importance to treat periodontitis. Among multiple cell types, fibroblast plays a central role in reestablishing functional periodontium. To enhance fibroblast activity, a novel metal-organic framework-based nanoplatform is fabricated using mesoporous Prussian blue (MPB) nanoparticles to load baicalein (BA), named MPB-BA. Drug release test displayed sustained BA release of MPB-BA. Cell proliferation, transwell migration and wound healing tests revealed accelerated fibroblast proliferation and migration for the established MPB-BA nanoplatform. Moreover, vinculin immunofluorescence staining, western blot and quantitative real-time PCR analysis showed up-regulated vinculin protein and integrin α5 and integrin β1 gene expressions for MPB-BA, suggesting improved cell adhesion. In addition, hematoxylin and eosin (H&E) and Masson trichromatic staining suggested superior anti-inflammatory and collagen fiber reconstruction effects for MPB-BA in a rat experimental periodontitis model in vivo. Our study may provide a promising strategy for the treatment of periodontitis.

Bone-Regenerative Ability of Platelet-Rich Plasma Following Sinus Augmentation with Anorganic Bovine Bone: A Systematic Review with Meta-Analysis

BACKGROUND

The objective of this systematic review is to assess the effect of the adjuvant use of platelet-rich plasma (PRP) and its type on new bone formation by anorganic bovine bone during maxillary sinus floor augmentation procedure.

METHODS

PubMed, Cochrane Central Register of Controlled Trials, and Ovid databases were searched for relevant studies published up to 16 September 2021. Randomized clinical trials (RCTs) and non-randomized controlled clinical trials (CCTs) that reported data on the new bone formation (measured by histomorphometric analysis) were considered. Risk of bias and quality assessment of included studies were evaluated following the Cochrane Handbook for Systematic Reviews of Interventions and the Risk Of Bias In Non-randomised Studies of Interventions (ROBINS-I) tool. Strength of evidence was assessed following the approach of the Agency for Healthcare Research and Quality (AHRQ) through its evidence-based practice center (AHRQ EPC). The meta-analysis was based on the primary outcome of newly formed bone, for which the standard mean difference was calculated.

RESULTS

After the application of eligibility criteria, six clinical trials (three RCTs and three CCTs) covering 85 maxillary sinus floor elevation procedures were included. The pooled new bone formation value for PRP was 1.67 (95% CI: -0.15 to 3.49; I2: 86%), indicating the absence of significant effect. Plasma rich in growth factors (PRGF) was the pure PRP tested in five of the included studies. When sub-group (type of PRP) meta-analysis was performed, significantly higher new bone formation was observed in the PRGF group [2.85 (95% CI: 0.07 to 5.64; I2: 88%)] in comparison to the control group.

CONCLUSIONS

A beneficial effect on new bone formation after maxillary sinus floor elevation can be obtained when anorganic bovine bone is mixed with PRGF.

Autologous Platelet Rich Plasma (PRGF) Preserves Genomic Stability of Gingival Fibroblasts and Alveolar Osteoblasts after Long-Term Cell Culture

Plasma rich in growth factors (PRGF) has several applications in dentistry that may require repeated applications of PRGF. Furthermore, it has been used for ex vivo expansion of human origin cells for their clinical application. One of the most relevant issues in these applications is to guarantee the genetic stability of cells. In this study, the chromosomal stability of gingival fibroblasts and alveolar osteoblasts after long-term culture was evaluated. Cells were expanded with PRGF or foetal bovine serum (FBS) as a culture medium supplement until passage 7 or 8 for gingival fibroblast or alveolar osteoblasts, respectively. A comparative genomic hybridization (CGH) array was used for the genetic stability study. This analysis was performed at passage 3 and after long-term culture with the corresponding culture medium supplements. The cell proliferative rate was superior after PRGF culture. Array CGH analysis of cells maintained with all the three supplements did not reveal the existence of alterations in copy number or genetic instability. The autologous PRGF technology preserves the genomic stability of cells and emerges as a safe substitute for FBS as a culture medium supplement for the clinical translation of cell therapy.

The inclusion of leukocytes into platelet rich plasma reduces scaffold stability and hinders extracellular matrix remodelling

BACKGROUND

Scaffolds should have controllable degradation rate and allow cells to produce their own extracellular matrix. Platelet rich plasma (PRP) is a source of autologous growth factors and proteins embedded in a 3D fibrin scaffold. There is no consensus regarding the obtaining conditions and composition of PRPs. The aim of this study was to evaluate how the inclusion of leukocytes (L-PRP) in plasma rich in growth factors (PRGF) may alter the process of fibrinolysis. The effect of different combinations of cellular phenotypes with PRGF and L-PRP clots on both the fibrinolysis and matrix deposition process was also determined.

METHODS

PRGF and L-PRP clots were incubated for 14 days and D-dimer and type I collagen were determined in their conditioned media to evaluate clots' stability. For remodelling assays, gingival fibroblasts, alveolar osteoblasts and human umbilical vein endothelial cells (HUVEC) were seeded onto the two types of clots for 14 days. D-dimer, type I collagen, and laminin α4 were measured by ELISA kits in their conditioned media. Morphological and histological analysis were also performed. Cell proliferation was additionally determined RESULTS: PRGF clots preserved their stability as shown by the low levels of both D-dimer and collagen type I compared to those obtained for L-PRP clots. The inclusion of both gingival fibroblasts and alveolar osteoblasts stimulated a higher fibrinolysis in the PRGF clots. In contrast to this, the degradation rates of both PRGF and L-PRP clots remained unchanged after culturing with the endothelial cells. In all cases, type I collagen and laminin α4 levels were in line with the degree of clots' degradation. In all phenotypes, cell proliferation was significantly higher in PRGF than in L-PRP clots.

CONCLUSION

The inclusion of leukocytes in PRGF scaffolds reduced their stability, decreased cell number and slowed down cell remodelling.

Healing through the lens of immunothrombosis: Biology-inspired, evolution-tailored, and human-engineered biomimetic therapies

Evolution, from invertebrates to mammals, has yielded and shaped immunoclotting as a defense and repair response against trauma and infection. This mosaic of immediate and local wound-sealing and pathogen-killing mechanisms results in survival, restoration of homeostasis, and tissue repair. In mammals, immunoclotting has been complemented with the neuroendocrine system, platelets, and contact system among other embellishments, adding layers of complexity through interconnecting blood-born proteolytic cascades, blood cells, and the neuroendocrine system. In doing so, immunothrombosis endows humans with survival advantages, but entails vulnerabilities in the current unprecedented and increasingly challenging environment. Immunothrombosis and tissue repair appear to go hand in hand with common mechanisms mediating both processes, a fact that is underlined by recent advances that are deciphering the mechanisms of the repair process and of the biochemical pathways that underpins coagulation, hemostasis and thrombosis. This review is intended to frame both the universal aspects of tissue repair and the therapeutic use of autologous fibrin matrix as a biology-as-a-drug approach in the context of the evolutionary changes in coagulation and hemostasis. In addition, we will try to shed some light on the molecular mechanisms underlying the use of the autologous fibrin matrix as a biology-inspired, evolution-tailored, and human-engineered biomimetic therapy.

Anthocyanin complex niosome gel accelerates oral wound healing: In vitro and clinical studies

An anthocyanin complex (AC), composed of extracts of purple waxy corn and blue butterfly pea petals, and AC niosomes, bilayered vesicles of non-ionic surfactants, were compared in in vitro and clinical studies. Cultured fibroblasts subjected to a scratch wound were monitored for cell viability, cell migration, nuclear morphology and protein expression. Scratched cells showed accelerated wound healing activity, returning to normal 24 h after treatment with AC niosomes (0.002 mg/mL). Western blots and immunocytochemistry indicated upregulation of type I, III and IV collagens, fibronectin and laminins in AC niosome-treated scratched cells. A randomized block placebo-controlled double-blind clinical trial in 60 volunteers (18-60 years old) with oral wounds indicated that AC niosome gel accelerated wound closure, reduced pain due to the oral wounds and improved participants' quality of life more than AC gel, triamcinolone gel and placebo gel. These data are consistent with enhanced delivery of AC to fibroblasts by use of niosomes. AC niosomes activated fibroblasts within wounded regions and accelerated wound healing, indicating that AC niosomes have therapeutic potential.

The Management of Postsurgical Wound Complications with Plasma Rich in Growth Factors: A Preliminary Series

BACKGROUND

Postsurgical wound complications constitute a relevant public health issue because of their frequency. There is growing evidence regarding platelet-based autologous therapies that support their use in promoting cutaneous regeneration.

OBJECTIVE

To provide preliminary data regarding the potential benefit of plasma rich in growth factors (PRGF) in the management of postsurgical wound complications.

DESIGN

Three patients suffering from poorly healing severe full-thickness wounds were treated with either one or a combination of different formulations derived from their own blood: autologous clot, fibrin membrane, injectable plasma, or topical ointment. Different treatment protocols are described, and follow-up results are reported.

RESULTS

Within 4 to 12 months, the treated wounds healed completely with no signs of infection, tissue necrosis, or functional impairment. No adverse events were reported.

CONCLUSION

Additional clinical trials with long-term follow-up periods and larger patient populations are needed to establish the efficacy of PRGF technology. However, these preliminary findings suggest that PRGF merits further randomized controlled studies exploring its capacity to accelerate re-epithelialization and restore functional integrity to cutaneous ulcers resulting from surgical complications.

Development and Optimization of Freeze-Dried Eye Drops Derived From Plasma Rich in Growth Factors Technology

Purpose

To investigate whether plasma rich in growth factors (PRGF) eye drops maintain their biological potential after a freeze drying process. The addition of a lyoprotectant like trehalose was also evaluated.

Methods

Blood from three healthy donors was collected to obtain eye drops by PRGF technology. The resultant eye drops were divided in four groups: PRGF, freeze-dried PRGF (PRGF lyo), and PRGF lyophilized mixed with 2,5% trehalose (PRGF lyo+2.5T) or 5% trehalose (PRGF lyof+5T). Chemical and biological characteristics were evaluated. Photorefractive keratectomy was performed on C57BL/6 mice which were divided in three treatment groups: control, PRGF, and PRGF lyo. Corneal wound healing and haze formation were evaluated macroscopically. Eyes were collected at 1, 2, 3, and 7 days after surgery, and were processed for histologic studies.

Results

The pH values of PRGF samples increased significantly after the lyophilization process. Osmolarity levels increased significantly in PRGF samples mixed with trehalose in comparison with PRGF samples without protectants. The freeze drying process maintained growth factors levels as well as the biological properties of PRGF eye drops even without the use of lyoprotectants. PRGF lyo treatment significantly decreased the re-epithelialization time and haze formation in photorefractive keratectomy-treated corneas regarding PRGF and control groups. Furthermore, the PRGF lyo group significantly decreased the number of smooth muscle actin-positive cells in comparison with the control group at each time of the study and at days 2 and 3 in the PRGF group.

Conclusions

The freeze drying process preserves the protein and growth factor content as well as the biological properties of PRGF eye drops, even without the use of protectants. Freeze-dried PRGF eye drops accelerate corneal tissue regeneration after photorefractive keratectomy in comparison with the control group.

Translational Relevance

Our study shows the feasibility to preserve the biological capability of PRGF eye drops as freeze-dried formulation, avoiding the addition of protectants.

The effect of non-thermal atmospheric pressure plasma application on wound healing after gingivectomy

Recent studies have indicated the potential benefits of Non-thermal atmospheric pressure plasma (NTAPP) as a novel therapeutic approach. The purpose of the current study was thus to assess the effect of NTAPP on gingival wound healing. Fifteen patients with bilaterally symmetrical gingival hyperplasia were included in the study. After gingivectomy and gingivoplasty, the left-hand side of the symmetrical surgical area was irradiated with NTAPP (plasma jet kINPen 11). Digital photographs of the gingival wounds were taken at baseline and days 3, 7, and 14. Wound epithelialisation was evaluated. Landry Wound Healing Index (WHI) scores and visual analogue scale (VAS) scores were also recorded. There were significant differences between the epithelialisation of the NTAPP-treated sites and the control sites after the surgical procedures. The NTAPP-treated sites had significantly smaller stained surface areas compared with the control sites on the 3rd, 7^th , and 14th days (P < .05). The NTAPP-treated sites had better WHI scores than the control sites throughout the follow-up period (P < .05). It can be concluded that NTAPP enhances epithelialisation and stimulates wound healing after gingivectomy and gingivoplasty. However, further clinical studies with larger sample sizes are needed to determine the exact benefits of NTAPP for gingival wound healing.

Platelet-Rich Plasma Modulates Gap Junction Functionality and Connexin 43 and 26 Expression During TGF-β1-Induced Fibroblast to Myofibroblast Transition: Clues for Counteracting Fibrosis

Skeletal muscle repair/regeneration may benefit by Platelet-Rich Plasma (PRP) treatment owing to PRP pro-myogenic and anti-fibrotic effects. However, PRP anti-fibrotic action remains controversial. Here, we extended our previous researches on the inhibitory effects of PRP on in vitro transforming growth factor (TGF)-β1-induced differentiation of fibroblasts into myofibroblasts, the effector cells of fibrosis, focusing on gap junction (GJ) intercellular communication. The myofibroblastic phenotype was evaluated by cell shape analysis, confocal fluorescence microscopy and Western blotting analyses of α-smooth muscle actin and type-1 collagen expression, and electrophysiological recordings of resting membrane potential, resistance, and capacitance. PRP negatively regulated myofibroblast differentiation by modifying all the assessed parameters. Notably, myofibroblast pairs showed an increase of voltage-dependent GJ functionality paralleled by connexin (Cx) 43 expression increase. TGF-β1-treated cells, when exposed to a GJ blocker, or silenced for Cx43 expression, failed to differentiate towards myofibroblasts. Although a minority, myofibroblast pairs also showed not-voltage-dependent GJ currents and coherently Cx26 expression. PRP abolished the TGF-β1-induced voltage-dependent GJ current appearance while preventing Cx43 increase and promoting Cx26 expression. This study adds insights into molecular and functional mechanisms regulating fibroblast-myofibroblast transition and supports the anti-fibrotic potential of PRP, demonstrating the ability of this product to hamper myofibroblast generation targeting GJs.

The use of plasma rich in growth factors (PRGF) in guided tissue regeneration and guided bone regeneration. A review of histological, immunohistochemical, histomorphometrical, radiological and clinical results in humans

BACKGROUND

Modern surgeries have advanced toward personalized minimal-invasive treatments with a high rate of clinical healing that facilitates the regeneration of tissues. One of the leading approaches to deliver endogenous plasma- and platelet-derived growth factors is the plasma rich in growth factors (PRGF). This narrative review determines the effects of using PRGF in different oral surgical procedures including alveolar ridge augmentation, socket preservation, sinus floor augmentation and periodontal regeneration.

METHODS

For this narrative review, a literature search was conducted using PubMed and Researchgate. A combination of the following text words was used to maximize search specificity and sensitivity: "platelet-rich plasma", "PRP", "PRGF", "Platelet-rich growth factor", "socket preservation", "Extraction", "infra-bony pockets", "sinus floor augmentation", "randomized clinical controlled trials", "Alveolar osteitis", "Periodontal regeneration", "guided bone regeneration", "guided tissue regeneration".

RESULTS

Investigations have generally agreed that PRGF can promote and accelerate the healing process. PRGF optimizes the patient's quality of life by reducing pain, swelling and inflammation rate and also accelerates regeneration of soft tissue and bone tissue regeneration as well.

CONCLUSIONS

There is increasing evidence to support the use of PRGF in oral surgical procedures in order to improve the healing processes of the oral soft and hard tissues.

Fractional microneedling radiofrequency in striae alba: Do growth factors add value?

BACKGROUND

Various treatment modalities have been applied to treat striae alba (SA) with low satisfaction rate. Fractional microneedling radiofrequency (FMR) provides deep dermal coagulation, thereby inducing collagen synthesis and tissue tightening. The addition of platelet-derived lyophilized growth factors may add to the effect of FMR.

OBJECTIVES

To evaluate and compare the efficacy and safety of FMR alone or combined with lyophilized growth factors in the treatment of SA.

METHODS

In this left-right comparative study, 25 patients suffering from SA on the abdomen received four sessions of FMR with lyophilized growth factors on one side and with saline (as placebo) on the other side at 4 weeks interval. Photographic and biopsy documentation of the progress of the SA was carried out before the start of the treatment and 4 weeks after the last session. Calculation of the width of SA before treatment and after 4 sessions was done by Adobe Photoshop CS6.

RESULTS

There was a significant improvement in SA width after treatment in both the lyophilized growth factors (P = <.0001) and placebo sides (P = <.0001), the lyophilized growth factors being superior (P = .002). Patient satisfaction was more on the lyophilized growth factors (LGF) side (P = .034). Erythema and hyperpigmentation were less on the lyophilized growth factors side. Histopathologically, both showed improvement with no difference between LGF and placebo (epidermal thickness (P = .456), collagen content (P = .297), elastin content (P = .239)).

CONCLUSION

The combination of FMR and lyophilized growth factors improves SA outcome.

Pure platelet-rich plasma facilitates the repair of damaged cartilage and synovium in a rabbit hemorrhagic arthritis knee model

Objective

Hemorrhagic arthritis (HA) is a common disease of the musculoskeletal system caused by hemorrhage in the joints, leading to damages in the synovium and cartilage. Pure platelet-rich plasma (P-PRP) has been recently demonstrated to have anti-inflammatory and regenerative potential attributed to the various cytokines and growth factors that it contains. The aim of this study was to investigate the efficacy of P-PRP for the treatment of patients with mild and severe HA.

Methods

Autologous blood was withdrawn from the New Zealand rabbits and injected into their left and right knees to establish the HA models. The injection was performed once a week and repeated for 8 weeks to establish the mild HA models and for 16 weeks to establish the severe HA models. One hundred microliters of P-PRP was injected into the left HA knees, and the same volume of sterile 0.9% saline was injected into the corresponding right knees. MRI examination, H&E staining, and toluidine blue staining were respectively performed to evaluate the histological difference of synovium and cartilage between the P-PRP treated and untreated mild and severe groups. Normal knees were set as the control group.

Results

Pathological changes including tissue color, joint effusion, and synovium inflammation in the mild treated group were less severe compared to the other three experimental groups based on gross observation. The difference of joint cavity diameter between the mild treated and untreated groups was 2.67 ± 0.75 mm (95%CI, 1.20–4.14 mm), which was significantly larger than that between the severe treated and untreated groups (1.50 mm ± 0.48, 95%CI, 0.56–2.44 mm) (mean difference in joint cavity, 1.17 ± 0.32 mm; 95%CI, 0.49–1.85 mm; P < 0.01). MRI examination showed the synovitis and bone marrow edema were less severe in the treated groups compared to the corresponding untreated groups. H&E staining of the synovium suggested that the inflammation was much less and the cell number was much smaller in the treated than in the untreated HA knees in regard to both the mild and severe groups. The mean difference of cell number between the mild treated and untreated groups was 307.40 ± 14.23 (95%CI, 241.54–343.26; P < 0.001), which was 699.20 ± 82.80 (95%CI, 508.26–890.14; P < 0.001) between the severe treated and untreated groups. H&E staining and toluidine blue staining of the cartilage exhibited an obvious amelioration of inflammation and cartilage matrix loss after being treated with P-PRP for both groups, especially the mild group.

Conclusions

P-PRP was effective for the treatment of HA by inhibiting the development of synovitis and cartilage matrix loss in the affected joints, which was particularly obvious in the early-stage HA. This study supports the view that there is a great potential of P-PRP to be considered and used as a non-operative treatment for hemorrhagic arthritis at its early stage.

Periodontal regeneration: a bibliometric analysis of the most influential studies

Aim: The aim of the present study is to identify the most influential research articles and their main characteristics in the specialty of periodontal regeneration. Materials & methods: The Web of Science database advance search was performed in the subject category of 'Dentistry, Oral surgery and medicine' from January 2004 to October 2018 to retrieve citations data. Results: The majority of the articles were published in journals dedicated to the specialty of periodontology. Among the top-cited articles most emphasized study types were randomized control trials (n = 25) and reviews (n = 20). Conclusion: The present bibliometric analysis provides comprehensive information regarding the contributions made in the advancement of regenerative periodontal research. The authors from developed countries and affiliated with interdisciplinary/multicenter institutions have predominantly contributed.

Efficacy of plasma rich in growth factor used for dry socket management: a systematic review

Background

The main aim of this systematic review was to assess the dry socket management using plasma rich in growth factor (PRGF) in terms of pain relief, alveolar fossa healing, inflammation, the incidence of dry socket.

Material and Methods

PubMed, Cochrane Library, Elsevier Science Direct, China Biology Medicine (CBM), China National Knowledge Infrastructure (CNKI) and VIP database were searched for the related articles without language limitation. Two reviewers independently searched and evaluated relevant studies. This review has been registered in the website PROSPERO (CRD42018087252).

Results

28 articles were retrieved on PubMed and 98 on other electronic databases in the initial search. In the end, 4 randomized controlled trials (RCTs) were included, with a total of 139 patients enrolled. The descriptive results indicated that the use of PRGF may help reduce pain and inflammation after tooth extraction. To some extent, it is beneficial to the management of dry socket after extraction.

Conclusions

Quality assessment indicated all the included studies were judged to be at high risk of bias with low quality. Hence, it was impossible to make a recommendation for clinical use of PRGF based on the current evidence. Clearly, a multicenter clinical randomized controlled trial is needed urgent to evaluate the safety and efficacy of PRGF for dry socket management.

Key words:plasma rich in growth factor, PRGF, dry socket, systematic review.

Platelet-Rich Plasma and Bone Marrow-Derived Mesenchymal Stromal Cells Prevent TGF-β1-Induced Myofibroblast Generation but Are Not Synergistic when Combined: Morphological in vitro Analysis

The persistence of activated myofibroblasts is a hallmark of fibrosis of many organs. Thus, the modulation of the generation/functionality of these cells may represent a strategical anti-fibrotic therapeutic option. Bone marrow-derived mesenchymal stromal cell (MSC)-based therapy has shown promising clues, but some criticisms still limit the clinical use of these cells, including the need to avoid xenogeneic compound contamination for ex vivo cell amplification and the identification of appropriate growth factors acting as a pre-conditioning agent and/or cell delivery vehicle during transplantation, thus enabling the improvement of cell survival in the host tissue microenvironment. Many studies have demonstrated the ability of platelet-rich plasma (PRP), a source of many biologically active molecules, to positively influence MSC proliferation, survival, and functionality, as well as its anti-fibrotic potential. Here we investigated the effects of PRP, murine and human bone marrow-derived MSCs, and of the combined treatment PRP/MSCs on in vitro differentiation of murine NIH/3T3 and human HDFα fibroblasts to myofibroblasts induced by transforming growth factor (TGF)-β1, a well-known pro-fibrotic agent. The myofibroblastic phenotype was evaluated morphologically (cell shape and actin cytoskeleton assembly) and immunocytochemically (vinculin-rich focal adhesion clustering, α-smooth muscle actin and type-1 collagen expression). We found that PRP and MSCs, both as single treatments and in combination, were able to prevent the TGF-β1-induced fibroblast-myofibroblast transition. Unexpectedly, the combination PRP/MSCs had no synergistic effects. In conclusion, within the limitations related to an in vitro experimentation, our study may contribute to providing an experimental background for supporting the anti-fibrotic potential of the combination PRP/MSCs which, once translated "from bench to bedside," could potentially offer advantages over the single treatments.

Freeze-dried versus fresh platelet-rich plasma in acute wound healing of an animal model

Aim: To compare freeze-dried and fresh platelet-rich plasma (PRP) preparations, in a pre-clinical study. Materials & methods: 30 Wistar male rats were used to compare and characterize human PRP which was applied at the perilesional area in an acute wound model, evaluated by macroscopical and histological analysis. Results: Despite the increased growth factor concentration after the freeze-drying process, no change in the healing kinetics was observed in vivo. Nevertheless, a significant increased number of myofibroblasts was demonstrated in comparison with the fresh PRP group. We also demonstrated a significant increased percentage of blood vessels in comparison with controls in both the superficial and deep epidermis. Conclusion: These results encourage randomized clinical trials to evaluate the effectiveness of freeze-dried PRP for skin ulcer treatment.

PRGF as adjunct to DBB in maxillary sinus floor augmentation: histological results of a pilot split-mouth study

Background

Various technologies of autologous blood concentrates are currently evaluated for their potential to enhance bone formation.

Aim

To report on the histological outcome of maxillary sinus floor augmentation (MSFA) with deproteinized bovine bone (DBB) in combination with chair-side prepared autologous platelet-rich growth factor (PRGF), in comparison to that with DBB alone.

Materials and methods

Six partially edentulous patients with ≤ 3-mm residual bone height bilaterally in the posterior maxilla were subjected to MSFA with the lateral window technique, using DBB in combination with PRGF (PRGF System1 Vitoria, Spain) on one side or DBB alone on the contralateral side. Cylindrical biopsies from the augmented sinuses were collected during implant installation, ca. 6 months post-MSFA, and subjected to non-decalcified histological and histomorphometric evaluation.

Results

The collected biopsies varied in length (range 3.5–9.9 mm); consequently, the portion of the biopsy representing augmented tissues also varied (range 2.3–14.6 mm²). New bone formation with a trabecular appearance and numerous DBB particles in contact with the new bone or with loose connective tissue were observed. No differences in the relative volumes of bone formation were found in sinuses augmented with DBB + PRGF or DBB alone 6 months after MSFA (35.6 ± 8.26 mm and 37.8 ± 3.15 mm, respectively).

Conclusion and clinical implications

In conclusion, based on these preliminary results, PRGF as adjunct to DBB for MSFA, except from improved handling during the operation, does not appear to enhance nor interfere with bone formation inside the human sinus 6 months after MSFA, compared with the use of DBB alone.

Influence of Platelet-Rich and Platelet-Poor Plasma on Endogenous Mechanisms of Skeletal Muscle Repair/Regeneration

The morpho-functional recovery of injured skeletal muscle still represents an unmet need. None of the therapeutic options so far adopted have proved to be resolutive. A current scientific challenge remains the identification of effective strategies improving the endogenous skeletal muscle regenerative program. Indeed, skeletal muscle tissue possesses an intrinsic remarkable regenerative capacity in response to injury, mainly thanks to the activity of a population of resident muscle progenitors called satellite cells, largely influenced by the dynamic interplay established with different molecular and cellular components of the surrounding niche/microenvironment. Other myogenic non-satellite cells, residing within muscle or recruited via circulation may contribute to post-natal muscle regeneration. Unfortunately, in the case of extended damage the tissue repair may become aberrant, giving rise to a maladaptive fibrotic scar or adipose tissue infiltration, mainly due to dysregulated activity of different muscle interstitial cells. In this context, plasma preparations, including Platelet-Rich Plasma (PRP) and more recently Platelet-Poor Plasma (PPP), have shown advantages and promising therapeutic perspectives. This review focuses on the contribution of these blood-derived products on repair/regeneration of damaged skeletal muscle, paying particular attention to the potential cellular targets and molecular mechanisms through which these products may exert their beneficial effects.

Plasma rich in growth factors (PRGF) in intraoral bone grafting procedures: A systematic review

PURPOSE

This systematic review aimed at assessing the effects of PRGF in new bone formation, soft tissue healing and post-operative pain and swelling in sites that underwent ridge preservation, ridge augmentation and maxillary sinus augmentation procedures.

MATERIALS AND METHODS

A comprehensive literature search employing seven databases was conducted by two independent reviewers. Only randomized and non-randomized controlled clinical trials using PRGF alone or in combination with bone grafting materials were selected.

RESULTS

Overall, 919 studies were identified, of which a total of 8 articles were included in the qualitative analysis. Two of the selected studies reported on ridge preservation, one on ridge augmentation and five on maxillary sinus augmentation. Positive results were recorded for soft tissue healing and post-operative pain and swelling following these procedures. However, outcomes of PRGF on new bone formation post extraction and on maxillary sinus augmentation when combined with other biomaterials were conflicting. Meta-analysis could not be conducted for any variables due to the heterogeneity of selected studies.

CONCLUSION

Limited evidence exists on the effects of PRGF in different intraoral bone grafting procedures, with some benefit reported on soft tissue healing and post-operative symptomatology. As this platelet concentrate is commonly used in clinical practice, further research is needed to fully assess its clinical indications and effectiveness.

Application of Autologous Platelet-Rich Plasma on Tooth Extraction Site Prevents Occurence of Medication-Related Osteonecrosis of the Jaws in Rats

This study evaluated the effects of local application of autologous platelet-rich plasma (PRP) on the tooth extraction site of rats presenting the main risk factors for medication-related osteonecrosis of the jaw (MRONJ). For seven weeks, senile rats were submitted to systemic treatment with vehicle (VEH and VEH-PRP) or 100 μg/Kg of zoledronate (ZOL and ZOL-PRP) every three days. After three weeks, the first lower molar was extracted. VEH-PRP and ZOL-PRP received PRP at the tooth extraction site. Euthanasia was performed at 28 days postoperatively. Clinical, histopathological, histometric and immunohistochemical analyses were carried out in histological sections from the tooth extraction site. ZOL showed lower percentage of newly formed bone tissue (NFBT), higher percentage of non-vital bone tissue (NVBT), as well as higher immunolabeling for TNFα and IL-1β. In addition, ZOL presented lower immunolabeling for PCNA, VEGF, BMP2/4, OCN and TRAP. VEH and ZOL-PRP showed improvement in the tooth extraction site wound healing and comparable percentage of NFBT, VEGF, BMP2/4 and OCN. Local application of autologous PRP proved a viable preventive therapy, which is safe and effective to restore tissue repair capacity of the tooth extraction site and prevent the occurrence of MRONJ following tooth extraction.

Plasma rich in growth factors for the treatment of dry eye from patients with graft versus host diseases

Purpose:

To evaluate the efficacy and safety of plasma rich in growth factors eye drops for the treatment of corneal and ocular surface disorders in patients with graft versus host disease.

Methods:

This retrospective and longitudinal study included graft versus host disease patients with ocular disorders. The resolution of corneal ulcers (area and density staining) was evaluated as primary outcome. Best corrected visual acuity, intraocular pressure, tear film breakup time, Schirmer test, ocular surface disease index, and visual analog score were evaluated as secondary outcomes. All variables were analyzed before and after plasma rich in growth factors treatment. The safety of plasma rich in growth factors treatment was also assessed.

Results:

Twelve patients (23 eyes) with ocular graft versus host disease were evaluated. Statistically significant improvement in the area (75.7%) and density (73.3%) of the corneal staining, in best corrected visual acuity (74.7%), in ocular surface disease index scale (75.4%), visual analog score frequency (81.4%) and visual analog score severity (81.9%), and an increase of 3.8 s in tear film breakup time and 6 mm in Schirmer test was observed after plasma rich in growth factors treatment (p < 0.001). Some potential modifiers of the therapeutic effect were identified. All patients achieved corneal stability without perforation risk. No adverse events associated with the plasma rich in growth factors were observed.

Conclusion:

Immunosafe plasma rich in growth factors eye drops for the treatment of patients with ocular graft versus host disease could be safe and effective, showing a high rate of corneal ulcer resolution and dry eye disease control. Plasma rich in growth factors eye drops may help to maintain corneal stability and prevent it against higher ocular complications.

Autologous fibrin scaffolds: When platelet- and plasma-derived biomolecules meet fibrin

The healing of vascularized mammalian tissue injuries initiate with hemostasis and clotting as part of biological defense system leading to the formation of a fibrin clot in which activated platelets are trapped to quickly stop bleeding and destroy microbials. In order to harness the therapeutic potential of biomolecules secreted by platelets and stemmed from plasma, blood deconstruction has allowed to yield autologous platelet-and plasma-derived protein fibrin scaffold. The autologous growth factors and microparticles stemmed from platelets and plasma, interact with fibrin, extracellular matrix, and tissue cells in a combinatorial, synergistic, and multidirectional way on mechanisms governing tissue repair. This interplay will induce a wide range of cell specifications during inflammation and repair process including but not limited to fibrogenesis, angiogenesis, and immunomodulation. As biology-as-a-drug approach, autologous platelet-and plasma-derived protein fibrin scaffold is emerging as a safe and efficacious natural human-engineered growth factor delivery system to repair musculoskeletal tissues, and skin and corneal ulcers and burns. In doing so, it acts as therapeutic agent not perfect but close to biological precision. However, this autologous, biocompatible, biodegradable, and long in vivo lasting strategy faces several challenges, including its non-conventional single dose-response effect, the lack of standardization in its preparation and application, and the patient's biological features. In this review, we give an account of the main events of tissue repair. Then, we describe the procedure to prepare autologous platelet-and plasma-derived protein fibrin scaffolds, and the rationale behind these biomaterials, and finally, we highlight the significance of strategic accuracy in their application.

Platelet-Rich Plasma, Adipose Tissue, and Scar Modulation

Level of Evidence: 4.

Differential profile of protein expression on human keratocytes treated with autologous serum and plasma rich in growth factors (PRGF)

Purpose

The main objective of this study is to compare the protein expression of human keratocytes treated with Plasma rich in growth factors (PRGF) or autologous serum (AS) and previously induced to myofibroblast by TGF-β1 treatment.

Methods

Blood from healthy donor was collected and processed to obtain AS and PRGF eye drops. Blood derivates were aliquoted and stored at -80°C until use. Keratocyte cells were pretreated for 60 minutes with 2.5 ng/ml TGF-β1. After that, cells were treated with PRGF, AS or with TGF-β1 (control). To characterize the proteins deregulated after PRGF and AS treatment, a proteomic approach that combines 1D-SDS–PAGE approach followed by LC–MS/MS was carried out.

Results

Results show a catalogue of key proteins in close contact with a myofibroblastic differentiated phenotype in AS treated-cells, whereas PRGF-treated cells show attenuation on this phenotype. The number of proteins downregulated after PRGF treatment or upregulated in AS-treated cells suggest a close relationship between AS-treated cells and cytoskeletal functions. On the other hand, proteins upregulated after PRGF-treatment or downregulated in AS-treated cells reveal a greater association with processes such as protein synthesis, proliferation and cellular motility.

Conclusion

This proteomic analysis helps to understand the molecular events underlying AS and PRGF-driven tissue regeneration processes, providing new evidence that comes along with the modulation of TGF-β1 activity and the reversion of the myofibroblastic phenotype by PRGF.

Platelet-Rich Plasma Prevents In Vitro Transforming Growth Factor-β1-Induced Fibroblast to Myofibroblast Transition: Involvement of Vascular Endothelial Growth Factor (VEGF)-A/VEGF Receptor-1-Mediated Signaling †

The antifibrotic potential of platelet-rich plasma (PRP) is controversial. This study examined the effects of PRP on in vitro transforming growth factor (TGF)-β1-induced differentiation of fibroblasts into myofibroblasts, the main drivers of fibrosis, and the involvement of vascular endothelial growth factor (VEGF)-A in mediating PRP-induced responses. The impact of PRP alone on fibroblast differentiation was also assessed. Myofibroblastic phenotype was evaluated by confocal fluorescence microscopy and western blotting analyses of α-smooth muscle actin (sma) and type-1 collagen expression, vinculin-rich focal adhesion clustering, and stress fiber assembly. Notch-1, connexin 43, and VEGF-A expression were also analyzed by RT-PCR. PRP negatively regulated fibroblast-myofibroblast transition via VEGF-A/VEGF receptor (VEGFR)-1-mediated inhibition of TGF-β1/Smad3 signaling. Indeed TGF-β1/PRP co-treated fibroblasts showed a robust attenuation of the myofibroblastic phenotype concomitant with a decrease of Smad3 expression levels. The VEGFR-1 inhibition by KRN633 or blocking antibodies, or VEGF-A neutralization in these cells prevented the PRP-promoted effects. Moreover PRP abrogated the TGF-β1-induced reduction of VEGF-A and VEGFR-1 cell expression. The role of VEGF-A signaling in counteracting myofibroblast generation was confirmed by cell treatment with soluble VEGF-A. PRP as single treatment did not induce fibroblast myodifferentiation. This study provides new insights into cellular and molecular mechanisms underpinning PRP antifibrotic action.

Platelet rich plasma for the management of hair loss: Better alone or in combination?

Platelet-rich plasma (PRP) and autologous protein-based treatments have recently emerged as a potential therapeutic approach for hair loss-related disorders including androgenetic alopecia and alopecia areata. The safety and efficacy of repeated intradermal injections of PRP has proved to promote hair growth in a number of randomized clinical trials. Biologically active proteins and cytokines released upon platelet activation have shown to induce folliculogenesis and activate the anagen growing phase of dormant bulbs. Interestingly, further studies have revealed that combining PRP with other hair loss-related products may enhance the final performance of the treatment. These synergistic approaches include Food and Drug Administration (FDA) approved drugs such as finasteride or minoxidil, bioactive macromolecules and cell-based therapies. Here, recent research involving alone or combined therapy with platelet-rich plasma for the management of hair loss-related disorders are outlined and future prospects are discussed.

Coronally advanced flap and connective tissue graft with or without plasma rich in growth factors (PRGF) in treatment of gingival recession

Background

Several researchers have tried to improve the results of gingival recession treatment techniques. One of the methods is to use growth factors The present study was undertaken to evaluate the effect of CAF (coronally advanced flap) + CTG (connective tissue graft) + PRGF (plasma rich in growth factors) in the treatment of Miller Class I buccal gingival recession.

Material and Methods

Twenty-two teeth with Miller Class I gingival recession in 6 patients 26 ‒ 47 years of age were included in a split-mouth designed randomized controlled trial (RCT). In each patient, one side was treated with CAF + CTG + PRGF (test) and the other side was treated with CAF + CTG (control). The following parameters were measured before surgery and up to 6 months after surgery on the mid-buccal surface of the tooth: keratinized tissue width (KTW), clinical attachment level (CAL), probing depth (PD), vertical recession depth (VRD), recession depth (RD), gingival thickness (GT), root coverage in percentage (RC%) and the distance between the CEJ and mucogingival junction (MGJL). Data were analyzed with paired t-test and repeated measures ANOVA.

Results

After 6 months noticeable improvements were observed in both groups in all the variables measured except for PD; however, the differences between the two groups were not significant. RC% was 80 ± 25% and 67 ± 28% in the test and control groups, respectively, after 6 months.

Conclusions

Both CAF + CTG + PRGF and CAF + CTG treatment modalities resulted in favorable root coverage; however, the addition of PRGF added no measurable significant effect. Key words:Connective tissue graft, dental root coverage, gingival recession, growth factors, mucogingival surgery, periodontal plastic surgery.

Comparative Evaluation of Antimicrobial Efficacy of Platelet-rich Plasma, Platelet-rich Fibrin, and Injectable Platelet-rich Fibrin on the Standard Strains of Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans

Context:

Platelet concentrates are commonly used to promote periodontal soft- and hard-tissue regeneration. Recently, their antimicrobial efficacy is also explored. Various platelet concentrates have evolved which differ in the centrifugation protocols. Porphyromonas gingivalis (Pg) and Aggregatibacter actinomycetemcomitans (Aa) have been found to have an important role in periodontal pathology.

Aims:

In this study, PRP, PRF, and I-PRF are compared for their antibacterial effect against Pg and Aa.

Materials and Methods:

Blood samples were obtained from ten systemically and periodontally healthy individuals. Platelet concentrates were prepared using standardized centrifugation protocol. Antimicrobial activity was examined on standard strains of Pg and Aa using well diffusion method.

Statistical Analysis Used:

Means for the width of zones of inhibition were calculated along with standard deviations, and the comparison was made using Wilcoxon signed-rank test.

Results:

In case of Pg, I-PRF had the widest zone of inhibition which was significantly wider as compared to PRF. Furthermore, PRP had significantly wider zone of inhibition against PRF. In case of Aa, PRP had wider zone of inhibition which was significantly wider as compared to that of PRF and I-PRF.

Conclusions:

All the three platelet concentrates PRP, PRF, and I-PRF have antibacterial activity, but PRP and I-PRF are more active as compared to PRF. I-PRF being autologous and easy to prepare can be a very useful adjunct to the surgical therapy in bringing down the bacterial count helping in wound healing and regeneration.

A novel personalized 3D injectable protein scaffold for regenerative medicine

Biomaterials should be designed to closely resemble the characteristics and functions of the native extracellular matrix to provide mechanical support and signals to direct biological events. Here we have developed a novel injectable plasma rich in growth factors (PRGF-Endoret)-based formulation that combines a thermal-denaturation step of plasma with an autologous fibrin crosslinking. Rheological and mechanical properties were evaluated. Additionally, the microstructure and biological capacity of the biomaterial was also characterized. This novel formulation exhibited ideal mechanical properties and a gel-like behavior with the ability to progressively release its growth factor load over time. The results also suggested that the novel injectable formulation is non-cytotoxic, biocompatible and suitable for cell ingrowth as it is deduced from the fibroblast proliferation within the scaffold. Finally, stimulation of both cell proliferation and matrix proteins synthesis demonstrated the regenerative potential of this autologous protein based injectable scaffold.

3D TECA hydrogel reduces cellular senescence and enhances fibroblasts migration in wound healing

This study was designed to investigate the effect of 3D TECA hydrogel on the inflammatory-induced senescence marker, and to assess the influence of the gel on the periodontal ligament fibroblasts (PDLFs) migration in wound healing in vitro. PDLFs were cultured with 20 ng/ml TNF-α to induce inflammation in the presence and absence of 50 µM 3D TECA gel for 14 d. The gel effect on the senescence maker secretory associated-β-galactosidase (SA-β-gal) activity was measured by a histochemical staining. Chromatin condensation and DNA synthesis of the cells were assessed by 4′,6-diamidino-2-phenylindole and 5-ethynyl-2′-deoxyuridine fluorescent staining respectively. For evaluating fibroblasts migration, scratch wound healing assay and Pro-Plus Imaging software were used. The activity of senescence marker, SA-β-gal, was positive in the samples with TNF-α-induced inflammation. SA-β-gal percentage is suppressed (>65%, P < 0.05) in the treated cells with TECA gel as compared to the non-treated cells. Chromatin foci were obvious in the non-treated samples. DNA synthesis was markedly recognized by the fluorescent staining in the treated compared to non-treated cultures. Scratch wound test indicated that the cells migration rate was significantly higher (14.9 µm²/h, P < 0.05) in the treated versus (11 µm²/h) for control PDLFs. The new formula of 3D TECA suppresses the inflammatory-mediated cellular senescence and enhanced fibroblasts proliferation and migration. Therefore, 3D TECA may be used as an adjunct to accelerate repair and healing of periodontal tissues.

Evolution, current status and advances in application of platelet concentrate in periodontics and implantology

Platelet concentrates (PC) [platelet-rich plasma (PRP) and platelet-rich fibrin (PRF)] are frequently used for surgical procedures in medical and dental fields, particularly in oral and maxillofacial surgery, plastic surgery and sports medicine. The objective of all these technologies is to extract all the elements from a blood sample that could be used to improve healing and promote tissue regeneration. Although leukocyte rich and leukocyte poor PRP's have their own place in literature, the importance of non-platelet components in a platelet concentrate remains a mystery. PC have come a long way since its first appearance in 1954 to the T-PRF, A-PRF and i-PRF introduced recently. These PC find varied applications successfully in periodontics and implant dentistry as well. However, the technique of preparation, standing time, transfer process, temperature of centrifuge, vibration, etc., are the various factors for the mixed results reported in the literature. Until the introduction of a proper classification of terminologies, the PC were known by different names in different countries and by different commercial companies which also created a lot of confusion. This review intends to clarify all these confusion by briefing the exact evolution of PC, their preparation techniques, recent advances and their various clinical and technical aspects and applications.

Balancing microbial and mammalian cell functions on calcium ion-modified implant surfaces

Implant integration is a complex process mediated by the interaction of the implant surface with the surrounding ions, proteins, bacteria, and tissue cells. Although most implants achieve long-term bone-tissue integration, preventing pervasive implant-centered infections demands further advances, particularly in surfaces design. In this work, we analyzed classical microrough implant surfaces (only acid etched, AE; sandblasted then acid etching, SB + AE) and a new calcium-ion-modified implant surface (AE + Ca) in terms of soft- and hard-tissue integration, bacterial adhesion, and biofilm formation. We cultured on the surfaces primary oral cells from gingiva and alveolar bone, and three representative bacterial strains of the oral cavity, emulating oral conditions of natural saliva and blood plasma. With respect to gingiva and bone cells and in the presence of platelets and plasma proteins, AE + Ca surfaces yielded in average 86% higher adhesion, 44% more proliferation, and triggered 246% more synthesis of extracellular matrix biomolecules than AE-unmodified controls. Concomitantly, AE + Ca surfaces regardless of conditioning with saliva and/or blood plasma showed significantly less bacterial adhesion (67% reduction in average) and biofilm formation (40% reduction in average) than unmodified surfaces. These results highlight the importance of a calcium-rich hydrated interface to favor mammalian cell functions over microbial colonization at implant surfaces. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 421-432, 2018.

Expression and significance of TIMP-3, PACAP and VIP in vaginal wall tissues of patients with stress urinary incontinence

The objective of the present study was to investigate whether tissue inhibitor of metalloproteinase-3 (TIMP-3), pituitary adenylate cyclase-activating polypeptide (PACAP), and vasoactive intestinal peptide (VIP) participate in the occurrence of female stress urinary incontinence (SUI) by measuring the expression levels of TIMP-3, PACAP, and VIP in the vaginal wall and analyzing their correlation to understand the pathogenesis of female SUI. Forty female patients who were admitted to our hospital for tension-free obturator tape surgery for treatment of SUI from April, 2012 to December, 2015 were selected as the study group. Forty patients who underwent vaginal or total abdominal hysterectomy for treatment of non-estrogen-related diseases during the same period were selected as the control group. Tissue samples from the anterior vaginal wall, located at twelve o'clock, were taken from both groups. The expression levels of TIMP-3, PACAP and VIP were detected by immunohistochemistry, and the correlation of integral optical density (IOD) among expressions of TIMP-3, PACAP, and VIP was investigated. The expression of TIMP-3 in vaginal wall tissues of the study group was lower than that of the control group (P<0.05). The expression of PACAP and VIP in vaginal tissues of the study group were lower than those of the control group (P<0.05). In the study group, the IOD of PACAP expression was significantly and positively correlated with that of VIP (r=0.873, P<0.05), the IOD of PACAP expression was significantly and positively correlated with that of TIMP-3 (r=0.802, P<0.05), and the IOD of VIP expression was significantly and positively correlated with that of TIMP-3 (r=0.716, P<0.05). In conclusion, TIMP-3, PACAP and VIP jointly participate in the occurrence of female SUI. Increasing the expression of TIMP-3, PACAP, and VIP, repairing neurons, and enhancing the elasticity of vaginal wall tissues may become a new way to treat female SUI.

Cytokines during periodontal wound healing: potential application for new therapeutic approach

Regeneration of periodontal tissues is one of the main goals of periodontal therapy. However, current treatment, including surgical approach, use of membrane to allow maturation of all periodontal tissues, or use of enamel matrix derivatives, presents limitations in their indications and outcomes leading to the development of new tissue engineering strategies. Several cytokines are considered as key molecules during periodontal destruction process. However, their role during each phase of periodontal wound healing remains unclear. Control and modulation of the inflammatory response and especially, release of cytokines or activation/inhibition in a time- and spatial-controlled manner may be a potential perspective for periodontal tissue engineering. The aim of this review was to summarize the specific role of several cytokines during periodontal wound healing and the potential therapeutic interest of inflammatory modulation for periodontal regeneration especially related to the expression sequence of cytokines.

Customized platelet-rich plasma with transforming growth factor β1 neutralization antibody to reduce fibrosis in skeletal muscle

The formation of fibrous tissue during the healing of skeletal muscle injuries leads to incomplete recovery of the injured muscle. Platelet-rich-plasma (PRP) contains beneficial growth factors for skeletal muscle repair; however, it also contains deleterious cytokines and growth factors, such as TGF-β1, that can cause fibrosis and inhibit optimal muscle healing.

OBJECTIVE

To test if neutralizing TGF-β1's action within PRP, through neutralization antibodies, could improve PRP's beneficial effect on skeletal muscle repair.

METHODS

PRP was isolated from in-bred Fisher rats. TGF-β1 neutralization antibody (Ab) was used to block the TGF-β1 within the PRP prior to injection. The effects of customized PRP (TGF-β1 neutralized PRP) on muscle healing was tested on a cardiotoxin (CTX) induced muscle injury model.

RESULTS

A significant increase in the numbers of regenerative myofibers was observed in the PRP and customized PRP groups compared to the untreated control. A significant decrease in collagen deposition was observed in customized PRP groups when compared to the control and PRP groups. Significantly enhanced angiogenesis and more Pax-7 positive satellite cells were found in the PRP and customized PRP groups compared to the control group. Macrophage infiltration was increased in the customized PRP groups when compared with the PRP group. More M2 macrophages were recruited to the injury site in the customized PRP groups when compared with the PRP and control groups.

CONCLUSION

Neutralizing TGF-β1 within PRP significantly promotes muscle regeneration while significantly reducing fibrosis. Not only did the neutralization reduce fibrosis, it enhanced angiogenesis, prolonged satellite cell activation, and recruited a greater number of M2 macrophages to the injury site which also contributed to the efficacy that the customized PRP had on muscle healing.

Non-thermal atmospheric pressure plasma increased mRNA expression of growth factors in human gingival fibroblasts

OBJECTIVES

The aim of this in vitro study was to investigate the effects of a non-thermal atmospheric pressure plasma jet (NTAPPJ) on the cellular activity of human gingival fibroblasts (HGF) for possible non-surgical application of it during gingival wound healing.

MATERIALS AND METHODS

HGF cells were exposed with NTAPPJ for 1, 2, and 4 min and were investigated for cellular attachment, cell viability, morphology of attached cells, proliferation rate, and messenger ribonucleic acid (mRNA) expression of various growth factors. Also, scavengers for chemicals produced by NTAPPJ were used to identify the chemical species responsible for the effects.

RESULTS

There was no significant change in the number of HGF cells attached or their proliferation following NTAPPJ exposure. Also, high cell viability resulted from exposure of all of HGF cells to NTAPPJ for 1, 2, and 4 min. However, cells were more stretched while the mRNA expressions of transforming growth factor and vascular endothelial growth factor were significantly increased following NTAPPJ exposure. Additionally, the scavenger test showed that nitric oxide is likely to be the chemical responsible for an increase of cellular activity.

CONCLUSION

The results demonstrated that the NTAPPJ increased mRNA expressions of growth factors in human gingival fibroblasts.

CLINICAL RELEVANCE

Application of NTAPPJ would be useful in gingival wound healing in clinics though additional studies confirming the effects would be needed.