RESUMO
BACKGROUND: Signal peptide-CUB-EGF domain-containing protein 3 (SCUBE3), a secreted multifunctional glycoprotein whose transcript expression is restricted to the tooth germ epithelium during the development of embryonic mouse teeth, has been demonstrated to play a crucial role in the regulation of tooth development. Based on this, we hypothesized that epithelium-derived SCUBE3 contributes to bio-function in dental mesenchymal cells (Mes) via epithelium-mesenchyme interactions. METHODS: Immunohistochemical staining and a co-culture system were used to reveal the temporospatial expression of the SCUBE3 protein during mouse tooth germ development. In addition, human dental pulp stem cells (hDPSCs) were used as a Mes model to study the proliferation, migration, odontoblastic differentiation capacity, and mechanism of rhSCUBE3. Novel pulp-dentin-like organoid models were constructed to further confirm the odontoblast induction function of SCUBE3. Finally, semi-orthotopic animal experiments were performed to explore the clinical application of rhSCUBE3. Data were analysed using one-way analysis of variance and t-tests. RESULTS: The epithelium-derived SCUBE3 translocated to the mesenchyme via a paracrine pathway during mouse embryonic development, and the differentiating odontoblasts in postnatal tooth germ subsequently secreted the SCUBE3 protein via an autocrine mechanism. In hDPSCs, exogenous SCUBE3 promoted cell proliferation and migration via TGF-ß signalling and accelerated odontoblastic differentiation via BMP2 signalling. In the semi-orthotopic animal experiments, we found that SCUBE3 pre-treatment-induced polarized odontoblast-like cells attached to the dental walls and had better angiogenesis performance. CONCLUSION: SCUBE3 protein expression is transferred from the epithelium to mesenchyme during embryonic development. The function of epithelium-derived SCUBE3 in Mes, including proliferation, migration, and polarized odontoblastic differentiation, and their mechanisms are elaborated for the first time. These findings shed light on exogenous SCUBE3 application in clinic dental pulp regeneration.
Assuntos
Polpa Dentária , Células-Tronco Mesenquimais , Animais , Humanos , Camundongos , Desenvolvimento Embrionário , Regeneração , Diferenciação Celular , Odontoblastos , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismoRESUMO
Age-related loss of muscle mass and function negatively impacts healthspan and lifespan. Satellite cells function as muscle stem cells in muscle maintenance and regeneration by self-renewal, activation, proliferation and differentiation. These processes are perturbed in aging at the stem cell population level, contributing to muscle loss. However, how representation of subpopulations within the human satellite cell pool change during aging remains poorly understood. We previously reported a comprehensive baseline of human satellite cell (Hu-MuSCs) transcriptional activity in muscle homeostasis describing functional heterogenous human satellite cell subpopulations such as CAV1+ Hu-MUSCs. Here, we sequenced additional satellite cells from new healthy donors and performed extended transcriptomic analyses with regard to aging. We found an age-related loss of global transcriptomic heterogeneity and identified new markers (CAV1, CXCL14, GPX3) along with previously described ones (FN1, ITGB1, SPRY1) that are altered during aging in human satellite cells. These findings describe new transcriptomic changes that occur during aging in human satellite cells and provide a foundation for understanding functional impact.
Assuntos
Músculo Esquelético , Células Satélites de Músculo Esquelético , Humanos , Idoso , Músculo Esquelético/fisiologia , Regeneração/fisiologia , Diferenciação Celular/genética , Envelhecimento/genética , Células-TroncoRESUMO
The regeneration and reconstruction of articular cartilage (AC) after a defect are often difficult. The key to the treatment of AC defects lies in regeneration of the defect site and regulation of the inflammatory response. In this investigation, a bioactive multifunctional scaffold was formulated using the aptamer Apt19S as a mediator for mesenchymal stem cell (MSC)-specific recruitment and the enhancement of cellular chondrogenic and inflammatory regulation through the incorporation of Mg2+. Apt19S, which can recruit MSCs in vitro and in vivo, was chemically conjugated to a decellularized cartilage extracellular matrix (ECM)-lysed scaffold. The results from in vitro experiments using the resulting scaffold demonstrated that the inclusion of Mg2+ could stimulate not only the chondrogenic differentiation of synovial MSCs but also the increased polarization of macrophages toward the M2 phenotype. Additionally, Mg2+ inhibited NLRP3 inflammasome activation, thereby decreasing chondrocyte pyroptosis. Subsequently, Mg2+ was incorporated into the bioactive multifunctional scaffold, and the resulting scaffold promoted cartilage regeneration in vivo. In conclusion, this study confirms that the combination of Mg2+ and aptamer-functionalized ECM scaffolds is a promising strategy for AC regeneration based on in situ tissue engineering and early inflammatory regulation.
Assuntos
Cartilagem Articular , Cartilagem Articular/fisiologia , Magnésio/farmacologia , Regeneração/fisiologia , Condrócitos , Engenharia Tecidual/métodos , Oligonucleotídeos , Condrogênese , Matriz Extracelular/metabolismo , Íons/metabolismo , Tecidos SuporteRESUMO
Zebrafish hearts can regenerate by replacing damaged tissue with new cardiomyocytes. Although the steps leading up to the proliferation of surviving cardiomyocytes have been extensively studied, little is known about the mechanisms that control proliferation and redifferentiation to a mature state. We found that the cardiac dyad, a structure that regulates calcium handling and excitation-contraction coupling, played a key role in the redifferentiation process. A component of the cardiac dyad called leucine-rich repeat-containing 10 (Lrrc10) acted as a negative regulator of proliferation, prevented cardiomegaly, and induced redifferentiation. We found that its function was conserved in mammalian cardiomyocytes. This study highlights the importance of the underlying mechanisms required for heart regeneration and their application to the generation of fully functional cardiomyocytes.
Assuntos
Cálcio , Miócitos Cardíacos , Animais , Miócitos Cardíacos/fisiologia , Peixe-Zebra/fisiologia , Sarcômeros , Proliferação de Células , Coração/fisiologia , Regeneração/fisiologia , MamíferosRESUMO
Salivary gland (SG) dysfunction, due to radiotherapy, disease, or aging, is a clinical manifestation that has the potential to cause severe oral and/or systemic diseases and compromise quality of life. Currently, the standard-of-care for this condition remains palliative. A variety of approaches have been employed to restore saliva production, but they have largely failed due to damage to both secretory cells and the extracellular matrix (niche). Transplantation of allogeneic cells from healthy donors has been suggested as a potential solution, but no definitive population of SG stem cells, capable of regenerating the gland, has been identified. Alternatively, mesenchymal stem cells (MSCs) are abundant, well characterized, and during SG development/homeostasis engage in signaling crosstalk with the SG epithelium. Further, the trans-differentiation potential of these cells and their ability to regenerate SG tissues have been demonstrated. However, recent findings suggest that the "immuno-privileged" status of allogeneic adult MSCs may not reflect their status post-transplantation. In contrast, autologous MSCs can be recovered from healthy tissues and do not present a challenge to the recipient's immune system. With recent advances in our ability to expand MSCs in vitro on tissue-specific matrices, autologous MSCs may offer a new therapeutic paradigm for restoration of SG function.
Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Glândulas Salivares , Qualidade de Vida , Regeneração , Células-TroncoRESUMO
After a muscle injury, a process comprising inflammation, repair, and regeneration must occur in a time-sensitive manner for skeletal muscle to be adequately repaired and regenerated. This complex process is assumed to be controlled by various myeloid cell types, including monocytes and macrophages, though the mechanism is not fully understood. Aryl hydrocarbon receptor nuclear translocator-like (Arntl or Bmal1) is a transcription factor that controls the circadian rhythm and has been implicated in regulating myeloid cell functions. In the present study, we generated myeloid cell-specific Arntl conditional knockout (cKO) mice to assess the role of Arntl expressed in myeloid cell populations during the repair process after muscle injury. Myeloid cell-specific Arntl deletion impaired muscle regeneration after cardiotoxin injection. Flow cytometric analyses revealed that, in cKO mice, the numbers of infiltrating neutrophils and Ly6Chi monocytes within the injured site were reduced on days 1 and 2, respectively, after muscle injury. Moreover, neutrophil migration and the numbers of circulating monocytes were significantly reduced in cKO mice, which suggests these effects may account, at least in part, for the impaired regeneration. These findings suggest that Arntl, expressed in the myeloid lineage regulates neutrophil and monocyte recruitment and is therefore required for skeletal muscle regeneration.
Assuntos
Doenças Musculares , Infiltração de Neutrófilos , Animais , Camundongos , Fatores de Transcrição ARNTL/metabolismo , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/metabolismo , Músculo Esquelético/metabolismo , Doenças Musculares/metabolismo , Células Mieloides/metabolismo , Regeneração/fisiologiaRESUMO
Processes that regulate size and patterning along an axis must be highly integrated to generate robust shapes; relative changes in these processes underlie both congenital disease and evolutionary change. Fin length mutants in zebrafish have provided considerable insight into the pathways regulating fin size, yet signals underlying patterning have remained less clear. The bony rays of the fins possess distinct patterning along the proximodistal axis, reflected in the location of ray bifurcations and the lengths of ray segments, which show progressive shortening along the axis. Here, we show that thyroid hormone (TH) regulates aspects of proximodistal patterning of the caudal fin rays, regardless of fin size. TH promotes distal gene expression patterns, coordinating ray bifurcations and segment shortening with skeletal outgrowth along the proximodistal axis. This distalizing role for TH is conserved between development and regeneration, in all fins (paired and medial), and between Danio species as well as distantly related medaka. During regenerative outgrowth, TH acutely induces Shh-mediated skeletal bifurcation. Zebrafish have multiple nuclear TH receptors, and we found that unliganded Thrab-but not Thraa or Thrb-inhibits the formation of distal features. Broadly, these results demonstrate that proximodistal morphology is regulated independently from size-instructive signals. Modulating proximodistal patterning relative to size-either through changes to TH metabolism or other hormone-independent pathways-can shift skeletal patterning in ways that recapitulate aspects of fin ray diversity found in nature.
Assuntos
Proteínas de Peixe-Zebra , Peixe-Zebra , Animais , Peixe-Zebra/fisiologia , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Hormônios Tireóideos/genética , Nadadeiras de Animais/fisiologia , Regeneração/fisiologiaRESUMO
The nucleosome is the fundamental subunit of chromatin. Nucleosome structures are formed by the combination of histone octamers and genomic DNA. Through a systematic and precise process of folding and compression, these structures form a 30-nm chromatin fibre that is further organized within the nucleus in a hierarchical manner, known as the 3D genome. Understanding the intricacies of chromatin structure and the regulatory mode governing chromatin interactions is essential for unravelling the complexities of cellular architecture and function, particularly in relation to cell fate determination, regeneration, and the development of diseases. Here, we provide a general overview of the hierarchical structure of chromatin as well as of the evolution of chromatin conformation capture techniques. We also discuss the dynamic regulatory changes in higher-order chromatin structure that occur during stem cell lineage differentiation and somatic cell reprogramming, potential regulatory insights at the chromatin level in organ regeneration, and aberrant chromatin regulation in diseases.
Assuntos
Cromatina , Nucleossomos , Cromatina/genética , DNA/genética , Diferenciação Celular/genética , RegeneraçãoRESUMO
A two-photon excited fluorescent probe CMB-1 has been rationally developed for the detection and regeneration of formaldehyde based on a novel nucleophilic addition of a secondary amine to FA and subsequential alcoholysis reactivity mechanism. It enables a specific turn-on response towards formaldehyde and facilitates the monitoring of exogenous and endogenous formaldehyde in living cells via both one- and two-photon microscopy, with minimal influence on its native homeostasis and local concentration.
Assuntos
Corantes Fluorescentes , Fótons , Humanos , Células HeLa , Formaldeído , RegeneraçãoRESUMO
Bioengineered corneal tissue is a promising therapeutic modality for the treatment of corneal blindness as a substitute for cadaveric graft tissue. In this study, we fabricated a collagen gel using ultraviolet-A (UV-A) light and riboflavin as a photosensitizer (PhotoCol-RB) as an in situ-forming matrix to fill corneal wounds and create a cohesive interface between the crosslinked gel and adjacent collagen. The PhotoCol-RB gels supported corneal epithelialization and exhibited higher transparency compared to physically crosslinked collagen. We showed that different riboflavin concentrations yielded gels with different mechanical and biological properties. In vitro experiments using human corneal epithelial cells (hCECs) showed that hCECs are able to proliferate on the gel and express corneal cell markers such as cytokeratin 12 (CK12) and tight junctions (ZO-1). Using an ex vivo burst assay, we also showed that the PhotoCol-RB gels are able to seal corneal perforations. Ex vivo organ culture of the gels filling lamellar keratectomy wounds showed that the epithelium that regenerated over the PhotoCol-RB gels formed a multilayer compared to just a double layer for those that grew over physically cross-linked collagen. These gels can be formed either in situ directly on the wound site to conform to the geometry of a defect, or can be preformed and then applied to the corneal wound. Our results indicate that PhotoCol-RB gels merit further investigation as a way to stabilize and repair deep and perforating corneal wounds.
Assuntos
Colágeno , Córnea , Humanos , Colágeno/farmacologia , Regeneração , Riboflavina/farmacologia , Géis/farmacologiaRESUMO
Cardiovascular diseases have been the leading cause of death in both urban and rural residents. Among them, heart failure, which develops from various heart diseases to the end stage, is the main cause of death. With the development of regenerative medicine, stem cell transplantation is expected to be a potential and promising treatment for heart failure. In recent years, basic research and clinical application research related to stem cells have been vigorously developed in China, and many latest achievements and progress have been obtained. However, relevant guidance documents are still needed to standardize and scale up clinical applications of stem cell transplantation. Therefore, experts from the Tissue Repair and Regeneration Branch of the Chinese Medical Association, by referring to the latest research results, discussed the treatment of heart failure by autologous stem cell transplantation and reached the following consensus. The key technical issues related to autologous stem cell transplantation were mainly expounded, and scientific suggestions were proposed to standardize and promote the clinical research and application of stem cells.
Assuntos
Insuficiência Cardíaca , Transplante de Células-Tronco Hematopoéticas , Humanos , Consenso , Transplante Autólogo , Insuficiência Cardíaca/terapia , Transplante de Células-Tronco , RegeneraçãoRESUMO
The limited self-repair capacity of articular cartilage has motivated the development of stem cell therapy based on artificial scaffolds that mimic the extracellular matrix (ECM) of cartilage tissue. In view of the specificity of articular cartilage, desirable tissue adhesiveness and stable mechanical properties under cyclic mechanical loads are critical for cartilage scaffolds. Herein, we developed an injectable and degradable organic-inorganic hybrid hydrogel as a cartilage scaffold based on polyhedral oligomeric silsesquioxane (POSS)-cored polyphosphate and polysaccharide. Specifically, acrylated 8-arm star-shaped POSS-poly(ethyl ethylene phosphate) (POSS-8PEEP-AC) was synthesized and cross-linked with thiolated hyaluronic acid (HA-SH) to form a degradable POSS-PEEP/HA hydrogel. Incorporation of POSS in the hydrogel increased the mechanical properties. The POSS-PEEP/HA hydrogel showed enzymatic biodegradability and favorable biocompatibility, supporting the growth and differentiation of human mesenchymal stem cells (hMSCs). The chondrogenic differentiation of encapsulated hMSCs was promoted by loading transforming growth factor-ß3 (TGF-ß3) in the hydrogel. In addition, the injectable POSS-PEEP/HA hydrogel was capable of adhering to rat cartilage tissue and resisting cyclic compression. Furthermore, in vivo results revealed that the transplanted hMSCs encapsulated in the POSS-PEEP/HA hydrogel scaffold significantly improved cartilage regeneration in rats, while the conjugation of TGF-ß3 achieved a better therapeutic effect. The present work demonstrated the potential of the injectable, biodegradable, and mechanically enhanced POSS-PEEP/HA hybrid hydrogel as a scaffold biomaterial for cartilage regeneration.
Assuntos
Cartilagem Articular , Células-Tronco Mesenquimais , Humanos , Ratos , Animais , Hidrogéis/farmacologia , Hidrogéis/metabolismo , Polifosfatos , Cartilagem Articular/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Condrogênese , Regeneração , Polissacarídeos/farmacologia , Tecidos Suporte , Engenharia TecidualRESUMO
PURPOSE OF REVIEW: Following cardiac injury, the heart has limited ability to regenerate leading to decreased efficiency and function. Cardiac reprogramming offers a promising treatment to ameliorate the damage caused by ischemia through conversion of cardiac fibroblasts to induced cardiomyocytes (iCMs). Here, we aim to highlight the recent advancements of the last 5 years by discussing the various aspects of cardiac reprogramming including characterization of the cardiac fibroblast, the endogenous environment of the heart, the molecular mechanisms during reprogramming, the epigenetic landscape, and the mechanics of delivering reprogramming factors. RECENT FINDINGS: Due to generally low efficiency of direct cardiac reprogramming, many researchers have continued to improve the efficiency of iCM induction and continued exploration of the basic science behind the technique. The field is continuing to optimize individual aspects of reprogramming that can be leveraged together to improve overall effectiveness. Over the last several years, knowledge regarding the process of direct cardiac reprogramming and the many factors that affect its efficiency has increased significantly. Individual aspects have continued to be optimized, and it will be essential going forward to synthesize this information. Cardiac reprogramming continues to advance towards clinical translatability.
Assuntos
Reprogramação Celular , Miócitos Cardíacos , Humanos , RegeneraçãoRESUMO
PURPOSE OF REVIEW: Heart failure leads to high mortality. The failing myocardium cannot often be rescued as heart regeneration is mostly compromised by disease progress. Stem cell therapy is a strategy under development to replace the impaired myocardium for recovery after heart injury. RECENT FINDINGS: Many studies have provided evidence of the beneficial effects of pluripotent stem cell-derived cardiomyocyte (CM) implantation into diseased rodent hearts, but there are still many challenges and limitations to replicating the same effects in large animal models for preclinical validation. In this review, we summarize progress in the use of pluripotent stem cell-derived CMs in large animal models based on three key parameters: species selection, cell source, and delivery. Most importantly, we discuss the current limitations and challenges that need to be solved to advance this technology to the translational stage.
Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Animais , Humanos , Miócitos Cardíacos , Modelos Animais , Regeneração , Diferenciação Celular , Modelos Animais de DoençasRESUMO
Volumetric muscle loss overwhelms skeletal muscle's ordinarily capable regenerative machinery, resulting in severe functional deficits that have defied clinical repair strategies. In this manuscript we pair the early in vivo functional response induced by differing volumetric muscle loss tissue engineering repair strategies that are broadly representative of those explored by the field (scaffold alone, cells alone, or scaffold + cells) to the transcriptomic response induced by each intervention. We demonstrate that an implant strategy comprising allogeneic decellularized skeletal muscle scaffolds seeded with autologous minced muscle cellular paste (scaffold + cells) mediates a pattern of increased expression for several genes known to play roles in axon guidance and peripheral neuroregeneration, as well as several other key genes related to inflammation, phagocytosis, and extracellular matrix regulation. The upregulation of several key genes in the presence of both implant components suggests a unique synergy between scaffolding and cells in the early period following intervention that is not seen when either scaffolds or cells are used in isolation; a finding that invites further exploration of the interactions that could have a positive impact on the treatment of volumetric muscle loss.
Assuntos
Músculo Esquelético , Tecidos Suporte , Humanos , Músculo Esquelético/fisiologia , Regeneração/fisiologia , Matriz Extracelular/metabolismo , Perfilação da Expressão Gênica , Engenharia Tecidual/métodosRESUMO
The degeneration of articular cartilage tissue is the most common cause of articular cartilage diseases such as osteoarthritis. There are limitations in chondrocyte self-renewal and conventional treatments. During cartilage regeneration and repair, growth factors are typically used to induce cartilage differentiation in stem cells. The role of thrombospondin-2 in cartilage formation has received much attention in recent years. This paper reviews the role of thrombospondin-2 in cartilage regeneration and the important role it plays in protecting cartilage from damage caused by inflammation or trauma and in the regenerative repair of cartilage by binding to different receptors and activating different intracellular signaling pathways. These studies provide new ideas for cartilage repair in clinical settings.
Assuntos
Doenças das Cartilagens , Cartilagem Articular , Humanos , Regeneração , Cartilagem Articular/lesões , Condrócitos , TrombospondinasRESUMO
Based on the concept of tissue engineering (Cells-Scaffold-Bioactive molecules), regenerative endodontics appeared as a new notion for dental endodontic treatment. Its approaches aim to preserve dental pulp vitality (pulp capping) or to regenerate a vascularized pulp-like tissue inside necrotic root canals by cell homing. To improve the methods of tissue engineering for pulp regeneration, numerous studies using in vitro, ex vivo, and in vivo models have been performed. This review explores the evolution of laboratory models used in such studies and classifies them according to different criteria. It starts from the initial two-dimensional in vitro models that allowed characterization of stem cell behavior, through 3D culture matrices combined with dental tissue and finally arrives at the more challenging ex vivo and in vivo models. The travel which follows the elaboration of such models reveals the difficulty in establishing reproducible laboratory models for dental pulp regeneration. The development of well-established protocols and new laboratory ex vivo and in vivo models in the field of pulp regeneration would lead to consistent results, reduction of animal experimentation, and facilitation of the translation to clinical practice.
