Defective cell migration causes delayed wound healing (WH) and chronic skin lesions. Autologous micrograft (AMG) therapies have recently emerged as a new effective and affordable treatment able to ...improve wound healing capacity. However, the precise molecular mechanism through which AMG exhibits its beneficial effects remains unrevealed. Herein we show that AMG improves skin re-epithelialization by accelerating the migration of fibroblasts and keratinocytes. More specifically, AMG-treated wounds showed improvement of indispensable events associated with successful wound healing such as granulation tissue formation, organized collagen content, and newly formed blood vessels. We demonstrate that AMG is enriched with a pool of WH-associated growth factors that may provide the starting signal for a faster endogenous wound healing response. This work links the increased cell migration rate to the activation of the extracellular signal-regulated kinase (ERK) signaling pathway, which is followed by an increase in matrix metalloproteinase expression and their extracellular enzymatic activity. Overall we reveal the AMG-mediated wound healing transcriptional signature and shed light on the AMG molecular mechanism supporting its potential to trigger a highly improved wound healing process. In this way, we present a framework for future improvements in AMG therapy for skin tissue regeneration applications.
Platelet rich plasma (PRP) and Micrografts containing human follicle mesenchymal stem cells (HF-MSCs) were tried as a potential treatment for androgenetic alopecia (AGA). However, little to no work ...has yet to be seen wherein the bio-molecular pathway of HF-MSCs or PRP treatments were analyzed. The aims of this work are to report the clinical effectiveness of HF-MSCs and platelet-rich plasma evaluating and reviewing the most updated information related to the bio-molecular pathway. Twenty-one patients were treated with HF-MSCs injections and 57 patients were treated with A-PRP. The Wnt pathway and Platelet derived-growth factors effects were analyzed. 23 weeks after the last treatment with mean hair thickness increments (29 ± 5.0%) over baseline values for the targeted area. 12 weeks after the last injection with A-PRP mean hair count and hair density (31 ± 2%) increases significantly over baseline values. The increment of Wnt signaling in Dermal Papilla Cells evidently is one of the principal factors that enhances hair growth. Signaling from mesenchymal stem cells and platelet derived growth factors positively influences hair growth through cellular proliferation to prolong the anagen phase (FGF-7), inducing cell growth (ERK activation), stimulating hair follicle development (β-catenin), and suppressing apoptotic cues (Bcl-2 release and Akt activation).
Human bone marrow-derived mesenchymal stem cells (hBM-MSCs) are considered a great promise in the repair and regeneration of bone. Considerable efforts have been oriented towards uncovering the best ...strategy to promote stem cells osteogenic differentiation. In previous studies, hBM-MSCs exposed to physical stimuli such as pulsed electromagnetic fields (PEMFs) or directly seeded on nanostructured titanium surfaces (TiO2) were shown to improve their differentiation to osteoblasts in osteogenic condition. In the present study, the effect of a daily PEMF-exposure on osteogenic differentiation of hBM-MSCs seeded onto nanostructured TiO2 (with clusters under 100 nm of dimension) was investigated. TiO2-seeded cells were exposed to PEMF (magnetic field intensity: 2 mT; intensity of induced electric field: 5 mV; frequency: 75 Hz) and examined in terms of cell physiology modifications and osteogenic differentiation. Results showed that PEMF exposure affected TiO2-seeded cells osteogenesis by interfering with selective calcium-related osteogenic pathways, and greatly enhanced hBM-MSCs osteogenic features such as the expression of early/late osteogenic genes and protein production (e.g., ALP, COL-I, osteocalcin and osteopontin) and ALP activity. Finally, PEMF-treated cells resulted to secrete into conditioned media higher amounts of BMP-2, DCN and COL-I than untreated cell cultures. These findings confirm once more the osteoinductive potential of PEMF, suggesting that its combination with TiO2 nanostructured surface might be a great option in bone tissue engineering applications.
Skeletal muscle regeneration is one of the major areas of interest in sport medicine as well as trauma centers. Three‐dimensional (3D) bioprinting (BioP) is nowadays widely adopted to manufacture 3D ...constructs for regenerative medicine but a comparison between the available biomaterial‐based inks (bioinks) is missing. The present study aims to assess the impact of different hydrogels on the viability, proliferation, and differentiation of murine myoblasts (C2C12) encapsulated in 3D bioprinted constructs aided to muscle regeneration. We tested three different commercially available hydrogels bioinks based on: (1) gelatin methacrylate and alginate crosslinked by UV light; (2) gelatin methacrylate, xanthan gum, and alginate‐fibrinogen; (3) nanofibrillated cellulose (NFC)/alginate‐fibrinogen crosslinked with calcium chloride and thrombin. Constructs embedding the cells were manufactured by extrusion‐based BioP and C2C12 viability, proliferation, and differentiation were assessed after 24 h, 7, 14, 21, and 28 days in culture. Although viability, proliferation, and differentiation were observed in all the constructs, among the investigated bioinks, the best results were obtained by using NFC/alginate‐fibrinogen‐based hydrogel from 7 to 14 days in culture, when the embedded myoblasts started fusing, forming at day 21 and day 28 multinucleated myotubes within the 3D bioprinted structures. The results revealed an extensive myotube alignment all over the linear structure of the hydrogel, demonstrating cell maturation, and enhanced myogenesis. The bioprinting strategies that we describe here denote a strong and endorsed approach for the creation of in vitro artificial muscle to improve skeletal muscle tissue engineering for future therapeutic applications.
Recent studies have reported that stem cells (human follicular fluid mesenchymal stem cells or hFF-MSCs) are present in ovarian follicular fluid (hFF) and that they have a proliferative and ...differentiative potential which is similar to that of MSCs derived from other adult tissue. These mesenchymal stem cells, isolated from human follicular fluid waste matter discarded after retrieval of oocytes during the IVF process, constitute another, as yet unutilized, source of stem cell materials. There has been little work on the compatibility of these hFF-MSCs with scaffolds useful for bone tissue engineering applications and the aim of this study was to evaluate the osteogenic capacity of hFF-MSCs seeded on bioglass 58S-coated titanium and to provide an assessment of their suitability for bone tissue engineering purposes. Following a chemical and morphological characterization with scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), cell viability, morphology and expression of specific osteogenic markers were examined after 7 and 21 days of culture. The hFF-MSCs seeded on bioglass and cultured with osteogenic factors, when compared with those seeded on tissue culture plate or on uncoated titanium, exhibited enhanced cell viability and osteogenic differentiation, as reflected by increased calcium deposition and increased ALP activity with expression and production of bone-related proteins. Taken together, these results demonstrate that MSCs from human follicular fluid waste materials can be easily cultured in titanium scaffolds coated with bioglass, having osteoinductive properties. This process has significant potential for regenerative medicine applications and indicates that hFF-MSCs may be a valid alternative to hBM-MSC cells in experimental models in bone tissue engineering.
Satellite cells are unipotent stem cells involved in muscle regeneration. However, the skeletal muscle microenvironment exerts a dominant influence over stem cell function. The cell intrinsic ...complexity of the skeletal muscle niche located within the connective tissue between fibers includes motor neurons, tendons, blood vessels, immune response mediators and interstitial cells. All these cell types modulate the trafficking of stimuli responsible of muscle fiber regeneration. In addition, several stem cell types have been discovered in skeletal muscle tissue, mainly located in the interstitium. The majority of these stem cells appears to directly contribute to myogenic differentiation, although some of them are mainly implicated in paracrine effects. This review focuses on adult stem cells, which have been used for therapeutic purposes, mainly in animal models of chronic muscle degeneration. Emerging literature identifies other myogenic progenitors generated from pluripotent stem cells as potential candidates for the treatment of skeletal muscle degeneration. However, adult stem cells still represent the gold standard for future comparative studies.
We report the study of novel biodegradable electrospun scaffolds from poly(butylene 1,4-cyclohexandicarboxylate-
-triethylene cyclohexanedicarboxylate) (P(BCE-
-TECE)) as support for in vitro and in ...vivo muscle tissue regeneration. We demonstrate that chemical composition, i.e., the amount of TECE co-units (constituted of polyethylene glycol-like moieties), and fibre morphology, i.e., aligned microfibrous or sub-microfibrous scaffolds, are crucial in determining the material biocompatibility. Indeed, the presence of ether linkages influences surface wettability, mechanical properties, hydrolytic degradation rate, and density of cell anchoring points of the studied materials. On the other hand, electrospun scaffolds improve cell adhesion, proliferation, and differentiation by favouring cell alignment along fibre direction (fibre morphology), also allowing for better cell infiltration and oxygen and nutrient diffusion (fibre size). Overall, C2C12 myogenic cells highly differentiated into mature myotubes when cultured on microfibres realised with the copolymer richest in TECE co-units (micro-P73 mat). Lastly, when transplanted in the tibialis anterior muscles of healthy, injured, or dystrophic mice, micro-P73 mat appeared highly vascularised, colonised by murine cells and perfectly integrated with host muscles, thus confirming the suitability of P(BCE-
-TECE) scaffolds as substrates for skeletal muscle tissue engineering.
This work focuses on formulating liposomes to be used in isolated kidney dynamic machine perfusion in hypothermic conditions as drug delivery systems to improve preservation of transplantable organs. ...The need mainly arises from use of kidneys from marginal donors for transplantation that are more exposed to ischemic/reperfusion injury compared to those from standard donors. Two liposome preparation techniques, thin film hydration and microfluidic techniques, are explored for formulating liposomes loaded with two model proteins, myoglobin and bovine serum albumin. The protein-loaded liposomes are characterized for their size by DLS and morphology by TEM. Protein releases from the liposomes are tested in PERF-GEN perfusion fluid, 4 °C, and compared to the in vitro protein release in PBS, 37 °C. Fluorescent liposome uptake is analyzed by fluorescent microscope in vitro on epithelial tubular renal cell cultures and ex vivo on isolated pig kidney in hypothermic perfusion conditions. The results show that microfluidics are a superior technique for obtaining reproducible spherical liposomes with suitable size below 200 nm. Protein encapsulation efficiency is affected by its molecular weight and isoelectric point. Lowering incubation temperature slows down the proteins release; the perfusion fluid significantly affects the release of proteins sensitive to ionic media (such as BSA). Liposomes are taken up by epithelial tubular renal cells in two hours’ incubation time.
Background: The use of body mass index (BMI) could lead to over/under estimation of fat mass percentage (FM%). An alternative index (inverted BMI, iBMI) has been proposed as a better estimator of FM% ...in adults, while its practical feasibility in children and adolescents has not been fully investigated.
Aim: To examine if iBMI can better estimate FM% than BMI in children/adolescents.
Subjects and methods: Height, weight, and triceps and subscapularis skinfolds were measured in 6686 schoolchildren aged 11-14-years-old. BMI and iBMI (squared height/weight) were calculated; FM% was estimated by skinfold thicknesses. The Pearson correlation coefficient and the coefficient of determination were obtained to test the best regression model between the indexes and FM%.
Results: FM% was linearly related to both indexes with R2 values that were overall > 0.7. No significant differences among the R2 values were found (p value = .2, ANOVA).
Conclusion: BMI persists as a robust index for health surveillance screening in children/adolescents, being very intuitive and ready-to-use. Inverted BMI may be more accurate within a cohort of adults who experience only ponderal modifications, directly implicated in the variation of FM. In conclusion, the BMI remains a quick, handy and intuitive predictor of FM%.
Bone regeneration is currently one of the most important and challenging tissue engineering approaches in regenerative medicine. Bone regeneration is a promising approach in dentistry and is ...considered an ideal clinical strategy in treating diseases, injuries, and defects of the maxillofacial region. Advances in tissue engineering have resulted in the development of innovative scaffold designs, complemented by the progress made in cell-based therapies. In vitro bone regeneration can be achieved by the combination of stem cells, scaffolds, and bioactive factors. The biomimetic approach to create an ideal bone substitute provides strategies for developing combined scaffolds composed of adult stem cells with mesenchymal phenotype and different organic biomaterials (such as collagen and hyaluronic acid derivatives) or inorganic biomaterials such as manufactured polymers (polyglycolic acid (PGA), polylactic acid (PLA), and polycaprolactone). This review focuses on different biomaterials currently used in dentistry as scaffolds for bone regeneration in treating bone defects or in surgical techniques, such as sinus lift, horizontal and vertical bone grafts, or socket preservation. Our review would be of particular interest to medical and surgical researchers at the interface of cell biology, materials science, and tissue engineering, as well as industry-related manufacturers and researchers in healthcare, prosthetics, and 3D printing, too.
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