BACKGROUND:The regenerative property of fat grafting has been described. However, it is not clear whether the clinical results are attributable to the stem cells or are linked to other components of ...the adipose tissue. This work is aimed at analysis of the histologic and ultrastructural changes of aged facial skin after injection of fat graft in addition to its stromal vascular fraction, obtained by centrifugation, and to compare the results with those obtained by the injection of expanded adipose-derived mesenchymal stem cells.
METHODS:This study was performed in six consecutive patients who were candidates for face lift and whose ages ranged between 45 and 65 years. The patients underwent sampling of fat by liposuction from the abdominal region. The injection of fat and its stromal vascular fraction or expanded mesenchymal stem cells was performed in the preauricular areas. Fragments of skin were removed before and 3 months after each treatment and analyzed by optical and electron microscopy.
RESULTS:After treatment with the autologous lipidic component and stromal vascular fraction, the skin showed a decrease in elastic fiber network (elastosis) and the appearance of new oxytalan elastic fibers in papillary dermis. The ultrastructural examination showed a modified tridimensional architecture of the reticular dermis and the presence of a richer microvascular bed. Similar results following treatment with expanded mesenchymal stem cells were observed.
CONCLUSION:This study demonstrates that treatment with either fat and stromal vascular fraction or expanded mesenchymal stem cells modifies the pattern of the dermis, representing a skin rejuvenation effect.
Different mesenchymal stromal cells (MSC) have been successfully isolated and expanded in vitro and nowadays they are tested in clinical trials for a wide variety of diseases. Whether all MSC express ...the same cell surface markers or have a similar secretion profile is still controversial, making it difficult to decide which stromal cell may be better for a particular application.
We isolated human mesenchymal stromal cells from bone marrow (BM), adipose tissue (AT) and Wharton's jelly (WJ) and cultured them in fetal bovine serum supplemented media. We evaluated proliferation, in vitro differentiation (osteogenic, adipogenic and chondrogenic potential), expression of cell surface markers and protein secretion using Luminex and ELISA assays.
Cell proliferation was higher for WJ-MSC, followed by AT-MSC. Differences in surface expression markers were observed only for CD54 and CD146. WJ-MSC secreted higher concentrations of chemokines, pro-inflammatory proteins and growth factors. AT-MSC showed a better pro-angiogenic profile and secreted higher amounts of extracellular matrix components and metalloproteinases.
Mesenchymal stromal cells purified from different tissues have different angiogenic, inflammatory and matrix remodeling potential properties. These abilities should be further characterized in order to choose the best protocols for their therapeutic use.
Platelet-rich plasma (PRP) is nowadays widely applied in different clinical scenarios, such as orthopedics, ophthalmology and healing therapies, as a growth factor pool for improving tissue ...regeneration. Studies into its clinical efficiency are not conclusive and one of the main reasons for this is that different PRP preparations are used, eliciting different responses that cannot be compared. Platelet quantification and the growth factor content definition must be defined in order to understand molecular mechanisms behind PRP regenerative strength. Standardization of PRP preparations is thus urgently needed.
PRP was prepared by centrifugation varying the relative centrifugal force, temperature, and time. Having quantified platelet recovery and yield, the two-step procedure that rendered the highest output was chosen and further analyzed. Cytokine content was determined in different fractions obtained throughout the whole centrifugation procedure.
Our method showed reproducibility when applied to different blood donors. We recovered 46.9 to 69.5% of total initial platelets and the procedure resulted in a 5.4-fold to 7.3-fold increase in platelet concentration (1.4 × 10(6) to 1.9 × 10(6) platelets/μl). Platelets were highly purified, because only <0.3% from the initial red blood cells and leukocytes was present in the final PRP preparation. We also quantified growth factors, cytokines and chemokines secreted by the concentrated platelets after activation with calcium and calcium/thrombin. High concentrations of platelet-derived growth factor, endothelial growth factor and transforming growth factor (TGF) were secreted, together with the anti-inflammatory and proinflammatory cytokines interleukin (IL)-4, IL-8, IL-13, IL-17, tumor necrosis factor (TNF)-α and interferon (IFN)-α. No cytokines were secreted before platelet activation. TGF-β3 and IFNγ were not detected in any studied fraction. Clots obtained after platelet coagulation retained a high concentration of several growth factors, including platelet-derived growth factor and TGF.
Our study resulted in a consistent PRP preparation method that yielded a cytokine and growth factor pool from different donors with high reproducibility. These findings support the use of PRP in therapies aiming for tissue regeneration, and its content characterization will allow us to understand and improve the clinical outcomes.
Angiogenesis is considered to mediate the beneficial effects of mesenchymal cell therapy in spinal cord injury. After a moderate balloon-compression injury in rats, injections of either human adipose ...tissue-derived stromal/stem cells (hADSCs) or their conditioned culture media (CM-hADSC) elicited angiogenesis around the lesion site. Both therapies increased vascular density, but the presence of hADSCs in the tissue was required for the full maturation of new blood vessels. Only animals that received hADSC significantly improved their open field locomotion, assessed by the BBB score. Animals that received CM-hADSC only, presented haemorrhagic areas and lack pericytes. Proteomic analyses of human angiogenesis-related factors produced by hADSCs showed that both pro- and anti-angiogenic factors were produced by hADSCs in vitro, but only those related to vessel maturation were detectable in vivo. hADSCs produced PDGF-AA only after insertion into the injured spinal cord. hADSCs attracted resident pericytes expressing NG2, α-SMA, PDGF-Rβ and nestin to the lesion, potentially contributing to blood vessel maturation. We conclude that the presence of hADSCs in the injured spinal cord is essential for tissue repair.
Silicosis is an occupational lung disease, characterized by irreversible and progressive fibrosis. Silica exposure leads to intense lung inflammation, reactive oxygen production, and extracellular ...ATP (eATP) release by macrophages. The P2X7 purinergic receptor is thought to be an important immunomodulator that responds to eATP in sites of inflammation and tissue damage. The present study investigates the role of P2X7 receptor in a murine model of silicosis. To that end wild-type (C57BL/6) and P2X7 receptor knockout mice received intratracheal injection of saline or silica particles. After 14 days, changes in lung mechanics were determined by the end-inflation occlusion method. Bronchoalveolar lavage and flow cytometry analyzes were performed. Lungs were harvested for histological and immunochemistry analysis of fibers content, inflammatory infiltration, apoptosis, as well as cytokine and oxidative stress expression. Silica particle effects on lung alveolar macrophages and fibroblasts were also evaluated in cell line cultures. Phagocytosis assay was performed in peritoneal macrophages. Silica exposure increased lung mechanical parameters in wild-type but not in P2X7 knockout mice. Inflammatory cell infiltration and collagen deposition in lung parenchyma, apoptosis, TGF-β and NF-κB activation, as well as nitric oxide, reactive oxygen species (ROS) and IL-1β secretion were higher in wild-type than knockout silica-exposed mice. In vitro studies suggested that P2X7 receptor participates in silica particle phagocytosis, IL-1β secretion, as well as reactive oxygen species and nitric oxide production. In conclusion, our data showed a significant role for P2X7 receptor in silica-induced lung changes, modulating lung inflammatory, fibrotic, and functional changes.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The pathological condition of obesity is accompanied by a dysfunctional adipose tissue. We postulate that subcutaneous, preperitoneal and visceral obese abdominal white adipose tissue depots could ...have stromal vascular fractions (SVF) with distinct composition and adipose stem cells (ASC) that would differentially account for the pathogenesis of obesity.
In order to evaluate the distribution of SVF subpopulations, samples of subcutaneous, preperitoneal and visceral adipose tissues from morbidly obese women (n = 12, BMI: 46.2±5.1 kg/m2) were collected during bariatric surgery, enzymatically digested and analyzed by flow cytometry (n = 12). ASC from all depots were evaluated for morphology, surface expression, ability to accumulate lipid after induction and cytokine secretion (n = 3).
A high content of preadipocytes was found in the SVF of subcutaneous depot (p = 0.0178). ASC from the three depots had similar fibroblastoid morphology with a homogeneous expression of CD34, CD146, CD105, CD73 and CD90. ASC from the visceral depot secreted the highest levels of IL-6, MCP-1 and G-CSF (p = 0.0278). Interestingly, preperitoneal ASC under lipid accumulation stimulus showed the lowest levels of all the secreted cytokines, except for adiponectin that was enhanced (p = 0.0278).
ASC from preperitoneal adipose tissue revealed the less pro-inflammatory properties, although it is an internal adipose depot. Conversely, ASC from visceral adipose tissue are the most pro-inflammatory. Therefore, ASC from subcutaneous, visceral and preperitoneal adipose depots could differentially contribute to the chronic inflammatory scenario of obesity.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background
In a previous study, the authors demonstrated that treatment with expanded adipose-derived stem cells or stromal vascular fraction (SVF)-enriched fat modify the pattern of the dermis in ...human beings, representing a skin rejuvenation effect. Considering that expanded stem cells require a cell factor, the authors wanted to assess similar results by replacing them with platelet-rich plasma (PRP), which is easier to obtain and for which an empirical regenerative effect has been already described.
Objectives
To determine if PRP injection could replace the cutaneous regenerative effect of adipose-derived stem cells.
Methods
This study was performed in 13 patients who were candidates for facelift. The patients underwent sampling of fat by liposuction from the abdomen and submitted to one of three protocols: injection of SVF-enriched fat or expanded adipose-derived stem cells or fat plus PRP in the preauricular areas. Fragments of skin were removed before and 3 months after treatment and analyzed by optical and electron microscopy.
Results
The use of fat plus PRP led to the presence of more pronounced inflammatory infiltrates and a greater vascular reactivity, increasing in vascular permeability and a certain reactivity of the nervous component. The addition of PRP did not improve the regenerative effect.
Conclusion
The use of PRP did not have significant advantages in skin rejuvenation over the use of expanded adipose-derived stem cells or SVF-enriched fat. The effect of increased vascular reactivity may be useful in pathological situations in which an intense angiogenesis is desirable, such as tissular ischemia.
Level of Evidence: 4
Therapeutic
Lycopene, a major carotenoid component of tomato, has a potential anticancer activity in many types of cancer. Epidemiological and clinical trials rarely provide evidence for mechanisms of the ...compound's action, and studies on its effect on cancer of different cell origins are now being done. The aim of the present study was to determine the effect of lycopene on cell cycle and cell viability in eight human cancer cell lines.
Human cell lines were treated with lycopene (1-5 μM) for 48 and 96 h. Cell viability was monitored using the method of MTT. The cell cycle was analyzed by flow cytometry, and apoptotic cells were identified by terminal deoxynucleotidyl transferase-mediated dUTP nick labeling (TUNEL) and by DAPI.
Our data showed a significant decrease in the number of viable cells in three cancer cells lines (HT-29, T84 and MCF-7) after 48 h treatment with lycopene, and changes in the fraction of cells retained in different cell cycle phases. Lycopene promoted also cell cycle arrest followed by decreased cell viability in majority of cell lines after 96 h, as compared to controls. Furthermore, an increase in apoptosis was observed in four cell lines (T-84, HT-29, MCF-7 and DU145) when cells were treated with lycopene.
Our findings show the capacity of lycopene to inhibit cell proliferation, arrest cell cycle in different phases and increase apoptosis, mainly in breast, colon and prostate lines after 96 h. These observations suggest that lycopene may alter cell cycle regulatory proteins depending on the type of cancer and the dose of lycopene administration. Taken together, these data indicated that the antiproliferative effect of lycopene was cellular type, time and dose-dependent.
Platelet-rich plasma (PRP) is increasingly used as a cell culture supplement, in order to reduce the contact of human cells with animal-derived products during in vitro expansion. The effect of ...supplementation changes on cell growth and protein production is not fully characterized.
Human mesenchymal stromal cells from bone marrow, adipose tissue and Wharton's Jelly were isolated and cultured in PRP-supplemented media. Proliferation, in vitro differentiation, expression of cell surface markers, mRNA expression of key genes and protein secretion were quantified.
10% PRP sustained five to tenfold increased cell proliferation as compared to 10% fetal bovine serum. Regarding cell differentiation, PRP reduced adipogenic differentiation and increased calcium deposits in bone marrow and adipose tissue-mesenchymal stromal cells. Wharton's Jelly derived mesenchymal stromal cells secreted higher concentrations of chemokines and growth factors than other mesenchymal stromal cells when cultured in PRP-supplemented media. Bone marrow derived mesenchymal stromal cells secreted higher concentrations of pro-inflammatory and pro-angiogenic proteins. Mesenchymal stromal cells isolated from adipose tissue secreted higher amounts of extracellular matrix components.
Mesenchymal stromal cells purified from different tissues have distinct properties regarding differentiation, angiogenic, inflammatory and matrix remodeling potential when cultured in PRP supplemented media. These abilities should be further characterized in order to choose the best protocols for their therapeutic use.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Introdução: Para uma regulamentação específica e implementação das novas tecnologias avançadas na clínica médica, é preciso refinar o conhecimento sobre as células utilizadas. Um dos maiores desafios ...está na dificuldade em determinar os mecanismos de funcionamento das células após a terapia. Objetivo: Compreender, usando os métodos de rastreamento celular em pacientes, a distribuição e a função de células usadas em terapias avançadas. Método: Este trabalho foi elaborado pelo levantamento de artigos científicos nas bases de dados internacionais e da legislação vigente sobre a utilização clínica das nanopartículas. Resultados: Constatamos que a nanotecnologia já é uma ferramenta de grande utilidade, pois diversas nanopartículas magnéticas já são aprovadas para uso clínico; elas podem ser incorporadas por células e visualizadas por imagens de ressonância magnética. O presente texto discute as perspectivas sobre uso de nanomedicamentos para rastreamento celular na clínica médica. Conclusões: A utilização das nanopartículas necessita a elaboração e aprovação de leis, guias e normas que orientem a indústria, como outros setores, sobre a caracterização dos nanomateriais e potenciais riscos à saúde humana, animal e ao meio ambiente.
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