Search Results (224)

Background: Platelet-rich plasma (PRP) plays a crucial role in chronic wound healing by releasing growth factors that regulate inflammation, promote angiogenesis, and stimulate tissue regeneration. Methods and Results: Here, an animal source of PRP, named ApiRegenin and derived from cultivated deer blood, was established. Specific protein and non-protein biomarkers—including nicotinamide, palmitic acid, IGF, and fibronectin—were validated to ensure batch-to-batch quality control. The pharmacological properties of ApiRegenin in cultured cells transfected with DNA encoding HRE and NF-κB reporter constructs were validated, serving as a functional control. In a skin-defective model of db/db diabetic mice, accelerated wound healing was observed following ApiRegenin treatment. Histological analysis revealed enhancements of re-epithelialization, granulation tissue formation, and collagen deposition. In parallel, the immunofluorescence staining of CD31, α-SMA, and VEGF was upregulated, indicating the promotion of angiogenesis. Furthermore, ApiRegenin treatment shifted the local immune microenvironment toward an M2-like macrophage phenotype, characterized by the downregulation of iNOS and the contrastive upregulation of Arg-1. At the molecular level, transcriptomic enrichment analysis suggested the prominent involvement of the HIF-1, PI3K-Akt, and TNF signaling pathways. Conclusions: These findings demonstrate that ApiRegenin effectively accelerates diabetic wound healing by promoting angiogenesis and modulating macrophage polarization. Full article

Equine osteoarthritis (OA) is a major cause of lameness and economic loss in horses. While platelet-rich plasma (PRP) has clinical potential, the biological effects of fresh PRP (F-PRP) and freeze-dried PRP (FD-PRP) remain insufficiently defined. This pilot study compared 25% and 50% F-PRP and FD-PRP in an interleukin-1β-induced equine cartilage-synovium explant co-culture model. PRP treatments reduced inflammatory responses, with significant downregulation of COX-2 and PGE2 expression, and 25% F-PRP showed the most consistent inhibition of nitric oxide production. PRP also significantly reduced glycosaminoglycan release and altered matrix-related gene expression; however, FD-PRP significantly upregulated MMP13, indicating a potential pro-catabolic response. Untargeted LC/MS metabolomics showed that F-PRP and FD-PRP were associated with changes in glucose, purine, amino acid, lipid, and nucleotide metabolism. Growth factor analysis further showed lower PDGF and TGF-β1 concentrations in FD-PRP than in F-PRP. Overall, F-PRP showed more consistent anti-inflammatory and matrix-protective effects, whereas FD-PRP requires further optimization and safety validation before clinical application. Full article

Platelet-rich fibrin (PRF) has been widely used in regenerative dentistry because of its potential to support tissue regeneration. Recently, modifications in PRF preparation protocols and tube surface characteristics have attracted attention because of their possible influence on fibrin organization and biologic activity. The present in vitro study aimed to evaluate the effects of nano-hydroxyapatite platelet-rich fibrin (HA-PRF) on gingiva-derived mesenchymal stem cells (GMSCs) by comparing it with leukocyte platelet-rich fibrin (L-PRF) and titanium platelet-rich fibrin (T-PRF). Gingival tissue and venous blood samples were obtained from a systemically healthy male volunteer. PRF membranes were prepared using conventional glass tubes, nano-hydroxyapatite-coated tubes, and titanium tubes. GMSCs were isolated, characterized, and cultured with PRF membranes. Cell viability and metabolic activity were evaluated using MTT analysis. Apoptosis and necrosis rates were assessed by Annexin V/PI flow cytometry. VEGF and TGF-β1 release levels were determined by ELISA, whereas IL-1β, IL-6, and TNF-α gene expression levels were analyzed using qRT-PCR. The HA-PRF and L-PRF groups demonstrated higher cell viability values compared with the T-PRF group on day 7. Annexin V/PI analysis revealed no statistically significant differences between the groups in terms of apoptosis and necrosis. Growth factor release and cytokine gene expression profiles demonstrated time-dependent biologic responses in all PRF membranes. Within the limitations of this study, HA-PRF showed no evidence of cytotoxicity and demonstrated biologic responses comparable to those observed with conventional L-PRF. Both HA-PRF and L-PRF generally exhibited more favorable cellular responses than T-PRF under the present experimental conditions. Full article

Background/Objectives: Non–small cell lung cancer (NSCLC) is a leading cause of cancer-related mortality, driven by invasive behavior and frequent resistance to systemic therapies. Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) benefit patients with EGFR-mutant NSCLC, but their efficacy is often limited by tumor-intrinsic and environmental resistance mechanisms. Benzo[a]pyrene (BaP), a ubiquitous polycyclic aromatic hydrocarbon from tobacco smoke, combustion, and dietary sources, is a known carcinogen; however, its role in modulating therapeutic responses is poorly understood. Studies, including ours, implicate the platelet-activating factor-receptor (PAFR) pathway in mediating environmental pollutant and therapy-induced effects on tumor growth and microvesicle particle (MVP) release. We hypothesized that PAFR activation mediates BaP-induced NSCLC progression and influences EGFR-TKI responses. Methods: We assessed the effects of BaP, PAFR agonist CPAF, EGFR-TKIs, and their combinations on cell viability, proliferation, migration, anchorage-independent growth, and MVP secretion. Results: BaP did not alter cell survival but significantly increased migration, growth, colony formation, and MVP release, similar to CPAF, and these effects were blocked by a PAFR antagonist or acid sphingomyelinase inhibitor. Notably, BaP did not significantly reduce EGFR-TKI efficacy at tested concentrations. Conclusions: These results show that environmental carcinogens modulate NSCLC behavior through PAFR signaling without compromising EGFR-TKI responsiveness, highlighting PAFR as a potential therapeutic target. Full article

Temporomandibular joint osteoarthritis (TMJ-OA) is a multifactorial degenerative disorder characterized by progressive cartilage degradation, subchondral bone remodeling, and chronic inflammation, leading to pain and functional impairment in affected individuals. Despite its clinical impact, effective disease-modifying treatments remain limited, highlighting the need for innovative therapeutic approaches for treating this condition in the future. This manuscript examines the biological rationale, clinical applications, and therapeutic potential of platelet-rich plasma (PRP) and injectable platelet-rich fibrin (i-PRF) in the management of TMJ-OA. As autologous platelet-derived biomaterials, PRP and i-PRF contain high concentrations of growth factors and bioactive molecules that can modulate inflammatory responses and support tissue repair. PRP is associated with a relatively rapid release of these mediators, whereas i-PRF forms a fibrin matrix that may enable a more sustained release profile. Current clinical evidence suggests that both therapies show potential to contribute to pain reduction and may facilitate improvements in mandibular function. However, substantial heterogeneity in preparation protocols, study designs, and outcome measures limits the comparability and generalizability of these findings to the general population. Overall, PRP and i-PRF represent promising, minimally invasive regenerative strategies for managing TMJ-OA. Full article

Bone tissue engineering requires biomaterials capable of simultaneously supporting regeneration and preventing infection. Platelet-rich fibrin (PRF) has been widely used due to its autologous origin and growth factor release, but its rapid resorption limits its clinical applications. Albumin-PRF (Alb-PRF) membranes were developed to improve stability, and their combination with carbonated nanostructured hydroxyapatite (nCHA) may further reinforce osteoconductive properties. In this proof-of-concept study, we fabricated Alb-PRF, Alb-nCHA-PRF, and Alb-nCHA-PRF + doxycycline (DOX) membranes and characterized their physicochemical, antimicrobial, and biological performance in vitro. Membrane stability was monitored for up to 14 days; DOX incorporation and release were evaluated by autofluorescence and spectrophotometry; antimicrobial activity was assessed against E. faecalis and S. aureus; and MG-63 osteoblast-like cells were used to test cytocompatibility, proliferation, mineralization, and alkaline phosphatase (ALP) activity. The release of 27 cytokines and growth factors was quantified by multiplex immunoassay. Alb-PRF exhibited morphological integrity and an enhanced trophic secretome, and supported proliferation and late mineralization. nCHA incorporation reduced cell proliferation and secretome output, while DOX conferred sustained antibacterial activity and enhanced early ALP expression even with attenuated cytokine release, positively impacting mineralization, when compared to nCHA alone. These preliminary results provide preliminary feasibility evidence that Alb-PRF can be engineered as a multifunctional scaffold combining antimicrobial and regenerative functions, though some trade-offs indicate the need for dose optimization and validation with in vivo models. Full article

Elevated levels of platelet-derived growth factor (PDGF) isoforms in fibrosis are implicated in driving a dysfunctional profibrotic fibroblast phenotype. This study investigated the differential effects of the five PDGF isoforms (AA, AB, BB, CC, and DD) in inducing neonatal dermal and fetal lung fibroblast contraction, proliferation, cytokine production, myofibroblast differentiation, and extracellular matrix (ECM) deposition. All PDGF isoforms, except PDGF-AA, increased contraction of 3-dimensional collagen I gels by dermal (p < 0.01) and lung fibroblasts (p < 0.05) compared to media control. PDGF-AB, BB, and CC enhanced proliferation only in dermal fibroblasts (p < 0.05). PDGF-BB induced profibrotic IL-11 cytokine release in dermal and lung fibroblasts (p < 0.0001) and IL-6 cytokine release in dermal fibroblasts (p < 0.05) compared to media control. None of the PDGF isoforms affected ECM synthesis or myofibroblast differentiation. Dermal fibroblasts exhibited elevated PDGF Receptor-β (PDGFRβ) expression (p < 0.01) and increased basal ERK1/2 phosphorylation (p < 0.05) compared to lung fibroblasts. In summary, PDGF modulates fibroblast functions in a tissue-specific manner, with PDGF-BB driving profibrotic processes in dermal fibroblasts through high PDGFRβ expression and ERK1/2 signalling. Further research is needed to explore the benefit of tissue and isoform-specific PDGF inhibition strategies in skin and lung fibrosis. Full article

Background: Post-episiotomy wound healing remains largely managed through supportive care, despite growing evidence that local biochemical conditions critically influence tissue regeneration. Lactic acid is of particular interest in this context because it is both an endogenous metabolic intermediate and a physiologic component of the vaginal microenvironment, where it contributes to acidic pH maintenance, microbial homeostasis, and mucosal protection. Beyond these local effects, lactate has emerged as a signaling metabolite involved in angiogenesis, immune regulation, and extracellular matrix remodeling, making it a relevant candidate for regenerative wound care. Methods: This narrative translational review integrates evidence from molecular biology, biomaterials science, and clinical obstetrics to examine the therapeutic potential of lactic acid-loaded hydrogels for post-episiotomy tissue repair. Literature from PubMed, Scopus, and Web of Science was analyzed to evaluate physicochemical design parameters, lactate-mediated signaling pathways, and available clinical outcomes. Results: Lactic acid may function both as a microenvironmental regulator and as a metabolic signal capable of stabilizing hypoxia-inducible factor-1α signaling, enhancing vascular endothelial growth factor expression, modulating macrophage polarization, and influencing fibroblast-mediated extracellular matrix synthesis. Hydrogel matrices provide tunable platforms for controlled lactate release, pH buffering, and mucosal compatibility. Clinical studies suggest improved epithelialization, reduced infection risk, and lower pain scores following topical lactic acid formulations in episiotomy repair. In parallel, platelet-rich plasma provides autologous growth factor enrichment that may complement regenerative signaling pathways. Conclusions: Integrating microenvironment stabilization through lactic acid-based hydrogels with biologically active regenerative strategies represents a promising direction for post-episiotomy wound healing. Further controlled trials and standardized biomaterial characterization are required to define optimal therapeutic protocols and confirm long-term clinical benefit. Full article

Background: Recombinant human growth hormone (rhGH) replacement therapy, administered to children with growth hormone deficiency (GHD), exerts pleiotropic effects on growth, metabolism, and tissue functions. Extracellular vesicles (EVs) are emerging mediators of inter-organ communication, but the effects of rhGH therapy on EV release in humans have not yet been investigated. Methods: In a preliminary prospective clinical study, children with GHD (n = 10; F/M = 5/5; age: 11.0 ± 2.7 years) were treated with rhGH for 6 months. Plasma samples were collected at baseline (T0) and after treatment (T6) to characterize the size distribution and tissue-derived composition of circulating EVs. Total EVs and EV subpopulations derived from monocytes/macrophages (CD14+), adipose tissue (FABP+), skeletal muscle (SCG+), endothelium (CD62E+), and platelets (CD42A+) were analyzed. Clinical, auxological/auxometric, and biochemical/metabolic parameters were assessed in parallel. Statistical methods included longitudinal analyses, interaction models, and adjustments for relevant covariates, including insulin-like growth factor 1 (IGF-1) and osteocalcin. Results: After 6 months of rhGH therapy, significant improvements in height velocity (cm/year and SDS) were observed, accompanied by increased circulating IGF-1 and osteocalcin levels. Hormone therapy induced no size-dependent changes in (total) EVs. Significant increases in CD14+ and FABP+ EVs were observed after treatment, without affecting the other tissue-derived EVs. Interaction analyses revealed that children with more severe GHD exhibited a stronger vesiculogenic response to rhGH. Furthermore, specific tissue-derived EVs were associated with metabolic/biochemical and auxological/auxometric parameters, including lipids, insulin resistance, and growth-related measures. Conclusions: When administered for six months, rhGH therapy seems to selectively change tissue-derived composition of circulating EVs in GHD children, particularly those derived from immune cells and adipose tissue. These preliminary findings suggest that EVs might represent an adjunctive component of GH-dependent inter-organ communication and might serve as biomarkers of treatment response and disease severity in pediatric endocrinology. Full article

Advances in regenerative medicine have positioned platelets and their derivatives—including platelet-rich plasma, platelet-rich fibrin, platelet lysate, extracellular vesicles, and purified growth factors—as promising interventions specifically for skin and bone aging, two clinically accessible tissues with robust preclinical and clinical evidence for platelet-derived component-based rejuvenation and regeneration. Because much of the available evidence comes from injury models or age-associated inflammatory/degenerative diseases, we explicitly distinguish pathology-targeted inflammation resolution/repair from rejuvenation under physiological aging. This review summarizes the composition and core bioactivities of platelet-derived products and delineates their putative anti-aging mechanisms, encompassing proangiogenic signaling, immunomodulation, attenuation of oxidative stress, regulation of extracellular matrix turnover, and stimulation of osteogenesis. We further evaluate emerging applications that expand therapeutic performance, such as platelet-mimetic delivery vehicles, engineered and sustained-release formulations, and targeted use of subcellular structures. Evidence from recent preclinical and clinical studies indicates favorable safety profiles and signals of efficacy across cutaneous rejuvenation and skeletal regeneration, while underscoring persistent challenges related to product standardization, dosing, and outcome measures. Collectively, platelet-based therapeutics represent a versatile platform with broad applicability to anti-aging interventions in skin and bone and strong potential for translation through continued bioengineering and clinical validation. However, because most available evidence comes from injury models or age-associated diseases (e.g., photoaging, chronic wounds, osteoarthritis, osteoporosis), direct extrapolation to physiological aging is limited; throughout, we explicitly contrast these contexts, specify their indication-specific endpoints, and summarize the main translational limitations. Full article

Background/Objectives: In clinical practice today, platelet concentrates are often used for topical surgical applications. They are biomaterials that can accelerate healing processes associated with oral and maxillofacial surgery as well as in several other clinical applications through the action of growth factors released by platelets at the surgical site. However, in most cases, the exact quantification of the released growth factors is challenging in both the short and long term. The aim of this study was to determine if early platelet activation and degranulation occur during the collection and utilization of platelet-rich plasma (PRP) in the surgical room, where, before its application, PRP undergoes a procedure of gelification via reactions with procoagulant agents. Methods: PRP was prepared from the blood samples of 39 patients following the modified Whitman protocol. The samples were then analyzed at four different time points (1, 6, and 24 h during preparation and clinical application in the surgery room) using flow cytometry and enzyme-linked immunosorbent assays (ELISAs) to investigate the platelet activation/degranulation and TGFβ release in the supernatant (SN) during storage and clinical application. The mean platelet count in the whole blood was 267.5 ± 48.58 × 10³/mL (range: 189–334 × 10³/mL), and the mean concentration was 2925.5 ± 833.37 × 10³/mL (range: 748–3453 × 10³/mL). Results: The activation and degranulation of platelet cells (measured via monoclonal antibodies: CD62p and CD63, respectively) demonstrated a progressive increase at 1 h, 6 h, 24 h, and after gelification. The TGFβ dosage in the supernatant (SN) at different times exhibited a similar trend, with a mean release of 18.36 ng/mL at 1 h, 21.96 ng/mL at 6 h, and 29.45 ng/mL at 24 h. After the gelification of the PRP, a significant reduction was observed, with a value of 15.52 ng/mL. Conclusions: The results reveal that the protocol used for the preparation, storage, and application of the PRP ensures a good-quality hemoderivative and that the platelet concentrate must be applied with the correct timing to support tissue healing processes. Full article

The efficacy of platelet-rich plasma (PRP) has long been associated with platelet concentration, yet clinical outcomes remain highly variable and frequently inconsistent. This review challenges the assumption that platelet count alone defines PRP efficacy, proposing instead that functional platelet quality and growth-factor bioactivity are equally critical determinants of therapeutic outcomes. Platelets act as carriers of bioactive molecules stored within alpha granules, including growth factors such as platelet-derived growth factor (PDGF), transforming growth factor beta (TGF-β), vascular endothelial growth factor (VEGF), and insulin-like growth factor (IGF), which orchestrate the cellular and molecular events of tissue repair. Variations in donor biology, age, metabolic status, and oxidative stress profoundly influence platelet functionality and growth-factor release. Likewise, centrifugation parameters, temperature control, and activation methods dictate whether these mediators are preserved or prematurely exhausted. Collectively, these findings reveal that platelet number alone cannot predict regenerative potency. The future of PRP standardization requires the integration of platelet quality indices, growth-factor quantification, and patient optimization protocols into clinical practice. By shifting focus from platelet enumeration to bioactivity assessment, regenerative medicine can achieve more consistent, personalized, and scientifically accurate outcomes. Full article

During tendon healing, collagen III expression precedes that of collagen I. The collagen I-to-III ratio at a certain time point post-laceration serves as an indicator of the healing status. Consequently, it is crucial to understand how different therapeutic approaches to support tendon healing affect the collagen I-to-III ratio in the extracellular matrix of a healing tendon, particularly across distinct anatomical zones. We compared the impact of a platelet-derived growth factor-BB (PDGF-BB) treatment via controlled release from coaxially electrospun DegraPol^® (Ab medica, Cerro Maggiore, Italy) hollow-fiber mesh with a treatment by the vehicle alone (no PDGF-BB) in the rabbit Achilles tendon full transection model and provide data on the collagen I-to-III ratio 3 weeks post-operation. For this purpose, we compared a dual-color Herovici staining to two single IHC labeling, for collagen I and collagen III, respectively. Herovici staining (HV) was expected to offer a more precise approach (pink-to-blue histogram) than the two separately labeled IHC stainings, both with chromogenic DAB labeling (red-to-green histogram), despite an anticipated positive correlation of the data assessed by these methods. Different zones were compared, i.e., native tendon tissue, reactive zone at interface to implant, hot zone within the core of the healing tendon and the zone within the scaffold, meaning the collagen deposited within the fibers of the implanted DegraPol^® tube, respectively. The analysis revealed that the ratios obtained via HV correlated weakly with the ratios obtained by IHC. Based on HV, PDGF-BB therapy led to higher collagen I-to-III ratios in all zones, except for the zone within the scaffold pores, while IHC did not reveal significant differences. Notably, collagen I-to-III ratios were not higher in immediate proximity, but rather distal from the PDGF-BB releasing implant, specifically in the core of the healing tendon tissue. Hence, a PDGF-BB therapy is suggestive of greater collagen maturation in specific zones of the healing tendon. Full article

Platelet-rich plasma (PRP) is a cornerstone of regenerative medicine, offering therapeutic potential across numerous clinical disciplines. Its efficacy relies on concentrated platelets and plasma components that release growth factors, cytokines, and extracellular vesicles to orchestrate tissue repair, immunomodulation, and angiogenesis. Recent findings have uncovered novel mechanisms, such as mitochondrial transfer from platelets to target cells and the delivery of bioactive microRNAs that regulate inflammation and metabolic reprogramming. However, despite its potential, PRP therapy is often limited by inconsistent results. In this review, we examine how patient-specific factors—including age, comorbidities, and lifestyle—and technical variables in preparation and storage, influence the biological quality of the final product. Therefore, standardizing protocols and accounting for individual biological variability are essential for achieving reproducible outcomes. In conclusion, PRP is a complex therapeutic agent whose success depends on both intrinsic bioactive content and extrinsic processing factors. Integrating these molecular insights with personalized patient assessment is crucial to optimizing PRP treatment procedures. Future research should focus on refining standardization to fully establish PRP as a precision medicine tool in regenerative therapy. Full article

The research on cytokine or growth factor (GF) release by leukaemic blasts is a largely unexplored area. This study aimed to evaluate the differential secretory potential of paediatric B-cell precursor and T-cell acute lymphoblastic leukaemia (BCP-ALL and T-ALL, respectively) and acute myeloid leukaemia cells (AMLs) for selected GFs, both basally and upon stimulation with phytohemagglutinin (PHA), lipopolysaccharide (LPS), or phorbol 12-myristate 13-acetate with ionophore A23187 (PMA + I). The concentrations of five GFs: granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), basic fibroblast growth factor (b-FGF), vascular endothelial growth factor (VEGF), and platelet-derived growth factor (PDGF) in the supernatants were measured using the Bio-Plex multiplex immunoassay. AML blasts showed the highest basal concentrations of G-CSF, GM-CSF, and VEGF. PHA and LPS stimulation non-selectively enhanced the secretion of G-CSF, GM-CSF, VEGF, and PDGF in BCP-ALL and AML blasts. PMA + I was the strongest GF release inducer, particularly for BCP-ALL and T-ALL blasts, with the latter also showing higher responsiveness to PHA and LPS. Our findings reveal differential, leukaemia-type dependent GF secretion patterns. Lineage-specific responses may be exploitable for targeted therapeutic approaches for distinct AL types. This study is the first to comprehensively assess the extracellular secretion of multiple GFs by paediatric AL cells in cultures using a Bio-Plex multiplex immunoassay. Full article