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1.
Regen Ther ; 26: 496-501, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39100535

RESUMO

Platelet-rich plasma (PRP) is the portion of plasma with a platelet concentration above baseline that is recovered through centrifugation of autologous blood. PRP therapy is currently used for wound healing and pain relief in diverse medical fields. Although there have been recent reports of adverse events (AEs) possibly related to PRP treatment, the safety profile of PRP treatment remains unclear. Therefore, this review discusses the risks inherent in PRP therapy and the current issues by surveying reports on AEs associated with PRP treatment within different fields. PubMed was searched for research articles referring to AEs associated with PRP therapy from inception to January 2024. Literature survey revealed that PRP therapy may involve several AEs, including postoperative infections, blindness, inflammation, allergic reactions, and nodule development. The most commonly reported AE was postoperative infections. Since PRP therapy generally proceeds in the process of blood collection, manufacturing, and administration to patients, it is conjectured that PRP may have been contaminated with microorganisms at some point in this series of processes, leading to bacterial infection. Additionally, because PRP cannot be sterilized like pharmaceuticals, it is important to prevent microbial contamination during each PRP treatment process. However, the specific process that involves the risk of microbial contamination remains unclear. To take measures to prevent microbial contamination of PRP, it may be necessary to elucidate the risk factors for microbial contamination during PRP treatment. It may be important to elucidate the effectiveness and risks of PRP therapy as well as to establish a follow-up system after PRP treatment. Currently, most reports of AEs related to PRP therapy are case reports; therefore, the accumulation of high-quality evidence and detailed verification are necessary to determine the causal relationship between PRP therapy and each AE.

2.
Transpl Int ; 37: 12708, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39100755

RESUMO

Liver transplantation is the only curative option for many liver diseases that end up in liver failure, and cholangiopathy remains a challenging complication post-liver transplant, associated with significant morbidity and potential graft loss. The low availability of organs and high demand for transplantation motivate scientists to find novel interventions. Organoids, as three-dimensional cell cultures derived from adult cells or induced pluripotent cells, may help to address this problem. Different types of organoids have been described, from which cholangiocyte organoids offer a high level of versatility and plasticity for a deeper study of liver disease mechanisms. Cholangiocytes can be obtained from different segments of the biliary tree and have shown a remarkable capacity to adapt to new environments, presenting an effective system for studying cholangiopathies. Studies using cholangiocyte organoids show promising results for disease modeling, where organoids offer fundamental features to recapitulate the complexities of tissues in vitro and uncover fundamental pathological pathways to potentially reveal therapeutic strategies for personalized medicine. Organoids could hold the potential for regeneration of injured livers, representing tools of clinical impact in regenerative medicine when tissue damage is already present.


Assuntos
Transplante de Fígado , Organoides , Humanos , Transplante de Fígado/efeitos adversos , Animais , Ductos Biliares/citologia , Fígado/citologia , Fígado/patologia , Células-Tronco Pluripotentes Induzidas/citologia , Medicina Regenerativa/métodos , Hepatopatias/cirurgia , Hepatopatias/terapia , Hepatopatias/patologia
3.
JOR Spine ; 7(3): e1363, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39104832

RESUMO

Background: Mechanical augmentation upon implantation is essential for the long-term success of tissue-engineered intervertebral discs (TE-IVDs). Previous studies utilized stiffer materials to fabricate TE-IVD support structures. However, these materials undergo various failure modes in the mechanically challenging IVD microenvironment. FlexiFil (FPLA) is an elastomeric 3D printing filament that is amenable to the fabrication of support structures. However, no present study has evaluated the efficacy of a flexible support material to preserve disc height and support the formation of hydrated tissues in a large animal model. Methods: We leveraged results from our previously developed FE model of the minipig spine to design and test TE-IVD support cages comprised of FPLA and PLA. Specifically, we performed indentation to assess implant mechanical response and scanning electron microscopy to visualize microscale damage. We then implanted FPLA and PLA support cages for 6 weeks in the minipig cervical spine and monitored disc height via weekly x-rays. TE-IVDs cultured in FPLA were also implanted for 6 weeks with weekly x-rays and terminal T2 MRIs to quantify tissue hydration at study endpoint. Results: Results demonstrated that FPLA cages withstood nearly twice the deformation of PLA without detrimental changes in mechanical performance and minimal damage. In vivo, FPLA cages and stably implanted TE-IVDs restored native disc height and supported the formation of hydrated tissues in the minipig spine. Displaced TE-IVDs yielded disc heights that were superior to PLA or discectomy-treated levels. Conclusions: FPLA holds great promise as a flexible and bioresorbable material for enhancing the long-term success of TE-IVD implants.

4.
Methods Mol Biol ; 2835: 17-27, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39105902

RESUMO

Human mesenchymal stromal cells (MSCs) have gained significant interest as cell-based therapeutics for organ restoration in the field of regenerative medicine. More recently, substantial attention has been directed toward cell-free therapy, achieved through the utilization of soluble factors possessing trophic and immunomodulatory properties present in the MSC secretome. This collection of soluble factors can be found either freely in the secretome or packed within its vesicular fraction, known as extracellular vesicles (EVs). MSCs can be derived from various tissue sources, each involving different extraction methods and yielding varying cell amounts. In this study, we describe a nonenzymatic procedure for a straightforward isolation of MSCs from the fetal dermis and the adult dermis. The results demonstrate the isolation of a cell population with a uniform MSC immunophenotype from the earliest passages (approximately 90% positive for the classical MSC markers CD90, CD105, and CD73, while negative for the hematopoietic markers CD34 and CD45, as well as HLA-DR). Additionally, we describe the procedures for cell expansion, banking, and secretome collection.


Assuntos
Separação Celular , Derme , Células-Tronco Mesenquimais , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Derme/citologia , Derme/metabolismo , Separação Celular/métodos , Imunofenotipagem , Técnicas de Cultura de Células/métodos , Biomarcadores , Células Cultivadas , Vesículas Extracelulares/metabolismo , Secretoma/metabolismo
5.
Cytokine ; 182: 156725, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39106575

RESUMO

During the aging process, elastin is degraded and the level of elastin-derived peptides (EDPs) successively increases. The main peptide released from elastin during its degradation is a peptide with the VGVAPG sequence. To date, several papers have described that EDPs or elastin-like peptides (ELPs) affect human mesenchymal stem cells (hMSCs) derived from different tissues. Unfortunately, despite the described effect of EDPs or ELPs on the hMSC differentiation process, the mechanism of action of these peptides has not been elucidated. Therefore, the aim of the present study was to evaluate the impact of the VGVAPG and VVGPGA peptides on the hMSC stemness marker and elucidation of the mechanism of action of these peptides. Our data show that both studied peptides (VGVAPG and VVGPGA) act with the involvement of ERK1/2 and c-SRC kinases. However, their mechanism of activation is probably different in hMSCs derived from adipose tissue. Both studied peptides increase the KI67 protein level in hMSCs, but this is not accompanied with cell proliferation. Moreover, the changes in the NANOG and c-MYC protein expression and in the SOX2 and POU5F1 mRNA expression suggest that EDPs reduced the hMSC stemness properties and could initiate cell differentiation. The initiation of differentiation was evidenced by changes in the expression of AhR and PPARγ protein as well as specific genes (ACTB, TUBB3) and proteins (ß-actin, RhoA) involved in cytoskeleton remodeling. Our data suggest that the presence of EDPs in tissue can initiate hMSC differentiation into more tissue-specific cells.

6.
Pain Physician ; 27(5): 283-302, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39087964

RESUMO

BACKGROUND: Platelet-rich plasma (PRP) is obtained by centrifuging autologous whole blood to extract a layer concentrated with platelets, growth factors found in platelet granules, and cytokines. These components work together to promote and facilitate the healing process at sites of injury. An increasing number of clinical studies are assessing the efficacy of PRP as a treatment for lower back pain. OBJECTIVES: Lumbar back pain is a significant cause of years lived with disability. This paper conducts a thorough review of clinical studies on intradiscal, facet-joint, epidural, and mixed-target PRP interventions in the lumbar spine. Furthermore, gaps in the current literature regarding lumbar spinal PRP injections are identified to help guide future clinical trials. STUDY DESIGN: Literature review. METHODS: An initial search was conducted using Ovid MEDLINE, focusing on PRP injections in the spine. Boolean operators were used to combine MeSH terms and key words such as "spine," "lumbar spine," "thoracic spine," "cervical spine," "intervertebral disc," "platelet-rich plasma," and "inject." The search revealed an absence of papers about PRP injections into the cervical and thoracic spine, so the review was written with a specific focus on the lumbar spine. For the purposes of this paper, the selected manuscripts were separated into categories of intradiscal, facet-joint, epidural, and mixed-target PRP injections. RESULTS: A multitude of case reports, case series, prospective clinical studies, and randomized controlled trials have yielded results supporting the use of intradiscal, facet-joint, and epidural PRP injections in the lumbar spine. However, a handful of papers suggest that PRP lacks efficacy in improving lumbar back pain and function. With the relative dearth of literature assessing the effects of spinal PRP injections, additional double-blinded randomized trials are needed. Important findings from available studies include the observation of PRP's increased efficacy over time, the correlation of the number of targeted injection sites with the efficacy of PRP injections, and the correlation of platelet count with PRP injections' efficacy. LIMITATIONS: There exists wide variability in PRP preparation protocols and in the methods of assessing PRP's therapeutic benefits between each study that evaluates PRP's effects in the lumbar spine. CONCLUSIONS: All clinical studies evaluating PRP as a form of treatment for the lumbar spine should include full transparency and details about the methods used for PRP preparation and injection. Future double-blinded randomized trials can fill in existing gaps by assessing the effects of platelet concentration and dose on the extent of clinical improvement as well as by establishing an expected timeline for clinical improvement after PRP injections. Cross-study standardization of which pain scoring systems to utilize for study evaluation would increase comparability among different papers.


Assuntos
Vértebras Lombares , Plasma Rico em Plaquetas , Humanos , Dor Lombar/terapia
7.
Int J Biol Macromol ; 277(Pt 3): 134398, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39097068

RESUMO

This study presents an innovative bi-layered three-dimensional skin-like nanopad (SLN) engineered for skin tissue regeneration. The SLN integrates a mechanically supportive polycaprolactone nanofibrous layer with a functional chitosan hydrogel film, mimicking natural skin. Our SLN exhibits superior flexibility, with a maximum elongation of 751.71 ± 125 % and exceptional porosity of 95 ± 4.5 %, ensuring effective exudate management due to its high water uptake capacity (4393 ± 72 %). FTIR analysis confirmed a distinctive fiber-hydrogel network within the SLN, which serves as a barrier against Staphylococcus aureus and Pseudomonas aeruginosa infiltration. In vitro cell viability assays with the human fibroblast have consistently demonstrated that 3D bi-layered SLN enhances fibroblast attachment, infiltration, and proliferation by 150 ± 20 %. In vivo studies in a rat model demonstrated significantly faster wound closure, with 60 % on day 7 and 87 % on day 10, compared to the 30 % and 60 % in controls, highlighting the efficacy of SLN. By mimicking the architecture of native skin, this biomimetic bi-layered SLN scaffold provides flexibility and support while accelerating in vivo wound closure by promoting fibroblast proliferation and infiltration. Customizable in size, depth, and shape, the engineered SLN has emerged as a promising platform for advanced wound care and tissue engineering.

8.
J Oral Biol Craniofac Res ; 14(5): 540-546, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39092136

RESUMO

Spheroids are spherical aggregates of cells. Normally, most of adherent cells cannot survive in suspension; however, if they adhere to each other and grow to a certain size, they can survive without attaching to the dish surface. Studies have shown that spheroid formation induces dedifferentiation and improves plasticity, proliferative capability, and differentiation capability. In particular, spontaneous spheroids represent a selective and efficient cultivation technique for somatic stem cells. Organoids are considered mini-organs composed of multiple types of cells with extracellular matrices that are maintained in three-dimensional culture. Although their culture environment is similar to that of spheroids, organoids consist of differentiated cells with fundamental tissue/organ structures similar to those of native organs. Organoids have been used for drug development, disease models, and basic biological studies. Spheroid culture has been reported for various cell types in the oral and craniofacial regions, including salivary gland epithelial cells, periodontal ligament cells, dental pulp stem cells, and oral mucosa-derived cells. For broader clinical application, it is crucial to identify treatment targets that can leverage the superior stemness of spheroids. Organoids have been developed from various organs, including taste buds, oral mucosa, teeth, and salivary glands, for basic biological studies and also with the goal to replace damaged or defective organs. The development of novel immune-tolerant cell sources is the key to the widespread clinical application of organoids in regenerative medicine. Further efforts to understand the underlying basic mechanisms of spheroids and organoids will lead to the development of safe and efficient next-generation regenerative therapies.

9.
Anesth Pain Med (Seoul) ; 19(3): 185-193, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39118332

RESUMO

Low back pain (LBP) is a prevalent and debilitating condition, particularly among older adults, with degenerative spinal disease being a major contributor. Regenerative therapy, which aims to repair and regenerate damaged spinal structures, has shown promise in providing long-term pain relief and functional improvement. This review focuses on the application and efficacy of regenerative therapies such as mesenchymal stem cells, platelet-rich plasma, and atelocollagen in older patients with LBP. Despite the potential benefits, there is a notable scarcity of studies specifically targeting the older population, and those available often have small sample sizes and limited age-related analyses. Our findings underscore the need for more comprehensive and well-designed clinical trials to evaluate the effectiveness of these therapies in older patients. Future research should prioritize larger age-specific studies to establish regenerative therapy as a viable and effective treatment option for LBP in the aging population.

10.
J Wound Care ; 33(8): 612-616, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39140406

RESUMO

There are several reasons for skin damage, including genetic factors, disorders, acute trauma, hard-to-heal wounds, or surgical interventions. Whatever the cause, wounds have a substantial impact on people who experience them, their caregivers and the healthcare system. Advanced wound care products have been researched and developed, providing an opportunity for faster and more complete healing. Tissue engineering (TE) is a promising strategy that can overcome limitations when choosing a graft for a wound. Amniotic membrane is a highly abundant, readily available, and inexpensive biological tissue that does not raise ethical concerns, with many applications in different fields of TE and regenerative medicine. It has attractive physical characteristics, such as elasticity, rigidity and mechanical strength, among others. The effects can also be potentiated by association with other substances, such as hyaluronic acid and growth factors. This paper describes new perspectives involving the use of amniotic membranes.


Assuntos
Âmnio , Engenharia Tecidual , Cicatrização , Humanos , Âmnio/transplante , Ferimentos e Lesões/terapia , Medicina Regenerativa/métodos
11.
Regen Med ; : 1-10, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39101612

RESUMO

Latest developments in the field of stem cell research and regenerative medicine compiled from publicly available information and press releases from non-academic institutions in May 2024.

12.
Int J Mol Sci ; 25(15)2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39125584

RESUMO

Interstitial cystitis/bladder pain Syndrome (IC/BPS) remains a mysterious and intricate urological disorder, presenting significant challenges to healthcare providers. Traditional guidelines for IC/BPS follow a hierarchical model based on symptom severity, advocating for conservative interventions as the initial step, followed by oral pharmacotherapy, intravesical treatments, and, in refractory cases, invasive surgical procedures. This approach embraces a multi-tiered strategy. However, the evolving understanding that IC/BPS represents a paroxysmal chronic pain syndrome, often involving extravesical manifestations and different subtypes, calls for a departure from this uniform approach. This review provides insights into recent advancements in experimental strategies in animal models and human studies. The identified therapeutic approaches fall into four categories: (i) anti-inflammation and anti-angiogenesis using monoclonal antibodies or immune modulation, (ii) regenerative medicine, including stem cell therapy, platelet-rich plasma, and low-intensity extracorporeal shock wave therapy, (iii) drug delivery systems leveraging nanotechnology, and (iv) drug delivery systems assisted by energy devices. Future investigations will require a broader range of animal models, studies on human bladder tissues, and well-designed clinical trials to establish the efficacy and safety of these therapeutic interventions.


Assuntos
Cistite Intersticial , Modelos Animais de Doenças , Cistite Intersticial/terapia , Humanos , Animais , Sistemas de Liberação de Medicamentos , Bexiga Urinária/patologia
13.
Stem Cell Rev Rep ; 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39145857

RESUMO

Osteoarthritis (OA) is a prevalent musculoskeletal disease affecting middle-aged and elderly individuals, with knee pain as a common complaint. Standard therapy approaches generally attempt to alleviate pain and inflammation, using various pharmacological and non-pharmacological options. However, the efficacy of these therapies in long-term tissue repair remains debated. As an alternative, regenerative medicine offers a promising strategy, with decreased adverse event rates and increasing evidence of safety and efficacy. This review will outline current advances in regenerative medicine for knee OA, emphasizing outpatient clinic-based therapies that use orthobiological and non-biological products. Different strategies based on orthobiologics are discussed as potential regenerative options for the management of knee OA. Cell-free therapies including platelet-rich plasma, autologous anti-inflammatories, exosomes, human placenta extract, and mitochondrial transplantation are discussed, focusing on their potential for cartilage regeneration. Additionally, cell-based therapies with regenerative properties including bone marrow aspirate concentrate, adipose stromal vascular fraction, microfat, nanofat, stem cell therapy, and genetically modified cells as part of orthobiologics, are being investigated. Also, this study is looking into non-biological approaches such as using gold-induced cytokines, extracorporeal shockwave therapy, and ozone therapy. The mechanisms of action, effectiveness, and clinical applications of each therapy are being explored, providing insights into their role in the management of knee OA.

14.
Front Med (Lausanne) ; 11: 1417920, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39131083

RESUMO

Introduction: This study explores the efficacy of Autologous Micrografts Technology (AMG) in treating chronic wounds refractory to traditional therapies. Methods: AMGs, derived from adipose tissue or dermis using a mechanical fragmentation process, were applied to patients with post-surgical dehiscence. A comprehensive evaluation of wound healing outcomes, including surface area reduction and complete healing, was conducted over a 90-day follow-up period. Additionally, the study investigated the cellular antioxidant activity of AMG solutions and characterized the exosomes obtained through mechanical disaggregation. Results: Results indicate significant improvements (p < 0.05) in wound healing, with 91.66% of patients showing at least a 50% reduction in lesion size and 75% achieving complete healing by day 90. Notably, AMG technology demonstrated immediate efficacy with fat-only application, while combined dermis and fat micrografts showed longer-term benefits, particularly in chronic wounds. The study also elucidated the mechanism of action of AMGs, highlighting their role in enhancing cellular antioxidant activity and exosome-mediated tissue regeneration. Discussion: Overall, these findings underscore the promising potential of AMG technology as a versatile and effective treatment option for chronic wounds, warranting further investigation into its mechanisms and clinical applications.

15.
Regen Ther ; 26: 478-488, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39131506

RESUMO

Stem cell (SC) transplantation has shown potential as a therapeutic approach for premature ovarian failure (POF). Despite this, no quantitative analysis has been conducted on the efficacy of SC therapy for POF in humans. To address this gap, the present study conducted a meta-analysis to evaluate the effectiveness of the transplantation of SC in improving ovarian function among POF patients. A systematic review in this regard by searching PubMed, ScienceDirect, clinicalTrial.gov, and Cochrane's library databases was conducted to identify relevant studies, while associated reviews were also considered. The extracted data included parameters such as estradiol (E2), follicle-stimulating hormone (FSH), follicle count (FC), ovarian weight (OW), number of pregnancies, and live birth. As per the combined effect taking the last follow-up time, the level of FSH and AMH for the SC group was lower than these were at the baseline as (SMD: 1.58, 95% CI: 0.76 to 3.92, P-value: 0.185 > 0.05, I2: 94.03%) and (SMD: 1.34, 95% CI: 0.77 to 1.92, P-value: 0.001 < 0.05, I2: 0%) respectively. While the means of E2 and OW for the SC group was higher than these were at the baseline as (SMD: -0.47, 95% CI: -0.73 to -0.21, P-value: 0.001 < 0.01, I2: 38.23%) and (SMD: -1.18, 95% CI: -2.62 to 0.26, P-value: 0.108 > 0.05, I2: 76.68%) respectively. The overall effect size measured with proportion of pregnancy and live birth at a 5% level of significance expected SC transplantation results were as (combined proportion: 0.09, 95% CI: 0.03 to 0.15, P-value: 0.002 < 0.05, I2: 46.29%) and (SMD: 0.09, 95% CI: 0.03 to 0.15, P-value: 0.003 < 0.05, I2: 1.76%) respectively. Based on the fixed-effects model, the estimated average log odds ratio of Follicles count was 1.0234 (95% CI: 0.1252 to 1.9216). Therefore, the average outcome differed significantly from zero (P-value: 0.0255 < 0.05) due to SC transplantation. These results suggest that using SCs to restore ovarian function may be viable for treating POF. However, larger and better-quality investigations would need to be conducted in the future due to the heterogeneity of the examined studies.

16.
Front Bioeng Biotechnol ; 12: 1391728, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39132253

RESUMO

Introduction: Collagen is extensively utilised in regenerative medicine due to its highly desirable properties. However, collagen is typically derived from mammalian sources, which poses several limitations, including high cost, potential risk of immunogenicity and transmission of infectious diseases, and ethical and religious constraints. Jellyfish-sourced type 0 collagen represents a safer and more environmentally sustainable alternative collagen source. Methods: Thus, we investigated the potential of jellyfish collagen-based hydrogels, obtained from Rhizostoma pulmo (R. pulmo) jellyfish, to be utilised in regenerative medicine. A variety of R. pulmo collagen hydrogels (RpCol hydrogels) were formed by adding a range of chemical crosslinking agents and their physicochemical and biological properties were characterised to assess their suitability for regenerative medicine applications. Results and Discussion: The characteristic chemical composition of RpCol was confirmed by Fourier-transform infrared spectroscopy (FTIR), and the degradation kinetics, morphological, and rheological properties of RpCol hydrogels were shown to be adaptable through the addition of specific chemical crosslinking agents. The endotoxin levels of RpCol were below the Food and Drug Administration (FDA) limit for medical devices, thus allowing the potential use of RpCol in vivo. 8-arm polyethylene glycol succinimidyl carboxyl methyl ester (PEG-SCM)-crosslinked RpCol hydrogels preserved the viability and induced a significant increase in the metabolic activity of immortalised human mesenchymal stem/stromal cells (TERT-hMSCs), therefore demonstrating their potential to be utilised in a wide range of regenerative medicine applications.

17.
Front Neurosci ; 18: 1425226, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39114486

RESUMO

Cochlear implants (CI) represent incredible devices that restore hearing perception for those with moderate to profound sensorineural hearing loss. However, the ability of a CI to restore complex auditory function is limited by the number of perceptually independent spectral channels provided. A major contributor to this limitation is the physical gap between the CI electrodes and the target spiral ganglion neurons (SGNs). In order for CI electrodes to stimulate SGNs more precisely, and thus better approximate natural hearing, new methodologies need to be developed to decrease this gap, (i.e., transitioning CIs from a far-field to near-field device). In this review, strategies aimed at improving the neural-electrode interface are discussed in terms of the magnitude of impact they could have and the work needed to implement them. Ongoing research suggests current clinical efforts to limit the CI-related immune response holds great potential for improving device performance. This could eradicate the dense, fibrous capsule surrounding the electrode and enhance preservation of natural cochlear architecture, including SGNs. In the long term, however, optimized future devices will likely need to induce and guide the outgrowth of the peripheral process of SGNs to be in closer proximity to the CI electrode in order to better approximate natural hearing. This research is in its infancy; it remains to be seen which strategies (surface patterning, small molecule release, hydrogel coating, etc.) will be enable this approach. Additionally, these efforts aimed at optimizing CI function will likely translate to other neural prostheses, which face similar issues.

18.
Cells ; 13(15)2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39120266

RESUMO

Among all of the materials used in tissue engineering in order to develop bioequivalents, collagen shows to be the most promising due to its superb biocompatibility and biodegradability, thus becoming one of the most widely used materials for scaffold production. However, current imaging techniques of the cells within collagen scaffolds have several limitations, which lead to an urgent need for novel methods of visualization. In this work, we have obtained groups of collagen scaffolds and selected the contrasting agents in order to study pores and patterns of cell growth in a non-disruptive manner via X-ray computed microtomography (micro-CT). After the comparison of multiple contrast agents, a 3% aqueous phosphotungstic acid solution in distilled water was identified as the most effective amongst the media, requiring 24 h of incubation. The differences in intensity values between collagen fibers, pores, and masses of cells allow for the accurate segmentation needed for further analysis. Moreover, the presented protocol allows visualization of porous collagen scaffolds under aqueous conditions, which is crucial for the multimodal study of the native structure of samples.


Assuntos
Colágeno , Alicerces Teciduais , Microtomografia por Raio-X , Alicerces Teciduais/química , Microtomografia por Raio-X/métodos , Colágeno/química , Colágeno/metabolismo , Engenharia Tecidual/métodos , Animais , Água/química , Porosidade , Técnicas de Cultura de Células em Três Dimensões/métodos , Humanos
19.
Cells ; 13(15)2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39120305

RESUMO

Transient receptor potential (TRP) channels are broadly implicated in the developmental programs of most tissues. Amongst these tissues, skeletal muscle and adipose are noteworthy for being essential in establishing systemic metabolic balance. TRP channels respond to environmental stimuli by supplying intracellular calcium that instigates enzymatic cascades of developmental consequence and often impinge on mitochondrial function and biogenesis. Critically, aminoglycoside antibiotics (AGAs) have been shown to block the capacity of TRP channels to conduct calcium entry into the cell in response to a wide range of developmental stimuli of a biophysical nature, including mechanical, electromagnetic, thermal, and chemical. Paradoxically, in vitro paradigms commonly used to understand organismal muscle and adipose development may have been led astray by the conventional use of streptomycin, an AGA, to help prevent bacterial contamination. Accordingly, streptomycin has been shown to disrupt both in vitro and in vivo myogenesis, as well as the phenotypic switch of white adipose into beige thermogenic status. In vivo, streptomycin has been shown to disrupt TRP-mediated calcium-dependent exercise adaptations of importance to systemic metabolism. Alternatively, streptomycin has also been used to curb detrimental levels of calcium leakage into dystrophic skeletal muscle through aberrantly gated TRPC1 channels that have been shown to be involved in the etiology of X-linked muscular dystrophies. TRP channels susceptible to AGA antagonism are critically involved in modulating the development of muscle and adipose tissues that, if administered to behaving animals, may translate to systemwide metabolic disruption. Regenerative medicine and clinical communities need to be made aware of this caveat of AGA usage and seek viable alternatives, to prevent contamination or infection in in vitro and in vivo paradigms, respectively.


Assuntos
Aminoglicosídeos , Antibacterianos , Canais de Potencial de Receptor Transitório , Humanos , Animais , Antibacterianos/farmacologia , Canais de Potencial de Receptor Transitório/metabolismo , Aminoglicosídeos/farmacologia , Músculo Esquelético/metabolismo , Músculo Esquelético/efeitos dos fármacos , Tecido Adiposo/metabolismo , Tecido Adiposo/efeitos dos fármacos
20.
Front Chem ; 12: 1417407, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39144698

RESUMO

Introduction: Bone tissue engineering seeks innovative materials that support cell growth and regeneration. Electrospun nanofibers, with their high surface area and tunable properties, serve as promising scaffolds. This study explores the incorporation of flaxseed extract, rich in polyphenolic compounds, into polyvinyl alcohol (PVA) nanofibers to improve their application in bone tissue engineering. Methods: High-performance liquid chromatography (HPLC) identified ten key compounds in flaxseed extract, including polyphenolic acids and flavonoids. PVA nanofibers were fabricated with 30 wt.% flaxseed extract (P70/E30) via electrospinning. We optimized characteristics like diameter, hydrophilicity, swelling behavior, and hydrolytic degradation. MG-63 osteoblast cultures were used to assess scaffold efficacy through cell adhesion, proliferation, viability (MTT assay), and differentiation. RT-qPCR measured expression of osteogenic genes RUNX2, COL1A1, and OCN. Results: Flaxseed extract increased nanofiber diameter from 252 nm (pure PVA) to 435 nm (P70/E30). P70/E30 nanofibers showed higher cell viability (102.6% vs. 74.5% for pure PVA), although adhesion decreased (151 vs. 206 cells/section). Notably, P70/E30 enhanced osteoblast differentiation, significantly upregulating RUNX2, COL1A1, and OCN genes. Discussion: Flaxseed extract incorporation into PVA nanofibers enhances bone tissue engineering by boosting osteoblast proliferation and differentiation, despite reduced adhesion. These properties suggest P70/E30's potential for regenerative medicine, emphasizing scaffold optimization for biomedical applications.

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