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1.
Carbohydr Polym ; 335: 122106, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38616080

RESUMO

More than 3000 proteins are now known to bind to glycosaminoglycans (GAGs). Yet, GAG-protein systems are rather poorly understood in terms of selectivity of recognition, molecular mechanism of action, and translational promise. High-throughput screening (HTS) technologies are critically needed for studying GAG biology and developing GAG-based therapeutics. Microarrays, developed within the past two decades, have now improved to the point of being the preferred tool in the HTS of biomolecules. GAG microarrays, in which GAG sequences are immobilized on slides, while similar to other microarrays, have their own sets of challenges and considerations. GAG microarrays are rapidly becoming the first choice in studying GAG-protein systems. Here, we review different modalities and applications of GAG microarrays presented to date. We discuss advantages and disadvantages of this technology, explain covalent and non-covalent immobilization strategies using different chemically reactive groups, and present various assay formats for qualitative and quantitative interpretations, including selectivity screening, binding affinity studies, competitive binding studies etc. We also highlight recent advances in implementing this technology, cataloging of data, and project its future promise. Overall, the technology of GAG microarray exhibits enormous potential of evolving into more than a mere screening tool for studying GAG - protein systems.


Assuntos
Bioensaio , Glicosaminoglicanos , Ligação Competitiva , Análise em Microsséries , Pesquisa
2.
Clin Transl Sci ; 17(4): e13776, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38545863

RESUMO

A quantitatively-driven evaluation of existing clinical data and associated knowledge to accelerate drug discovery and development is a highly valuable approach across therapeutic areas, but remains underutilized. This is especially the case for rare diseases for which development is particularly challenging. The current work outlines an organizational framework to support a quantitatively-based reverse translation approach to clinical development. This approach was applied to characterize predictors of the trajectory of cognition in Hunter syndrome (Mucopolysaccharidosis Type II; MPS-II), a rare X-linked lysosomal storage disorder, highly heterogeneous in its course. Specifically, we considered ways to refine target populations based on age, cognitive status, and biomarkers, that is, cerebrospinal fluid glycosaminoglycans (GAG), at trial entry. Data from a total of 138 subjects (age range 2.5 to 10.1 years) from Takeda-sponsored internal studies and external natural history studies in MPS-II were included. Quantitative analyses using mixed-effects models were performed to characterize the relationships between neurocognitive outcomes and potential indicators of disease progression. Results revealed a specific trajectory in cognitive development across age with an initial progressive phase, followed by a plateau between 4 and 8 years and then a variable declining phase. Additionally, results suggest a faster decline in cognition among subjects with lower cognitive scores or with higher cerebrospinal fluid GAG at enrollment. These results support differences in the neurocognitive course of MPS-II between distinct groups of patients based on age, cognitive function, and biomarker status at enrollment. These differences should be considered when designing future clinical trials.


Assuntos
Mucopolissacaridose II , Humanos , Pré-Escolar , Criança , Mucopolissacaridose II/diagnóstico , Mucopolissacaridose II/tratamento farmacológico , Glicosaminoglicanos/uso terapêutico , Biomarcadores , Progressão da Doença
3.
Int J Biol Macromol ; 265(Pt 1): 130696, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38458288

RESUMO

There has been significant progress in the field of three-dimensional (3D) bioprinting technology, leading to active research on creating bioinks capable of producing structurally and functionally tissue-mimetic constructs. Ti3C2Tx MXene nanoparticles (NPs), promising two-dimensional nanomaterials, are being investigated for their potential in muscle regeneration due to their unique physicochemical properties. In this study, we integrated MXene NPs into composite hydrogels made of gelatin methacryloyl (GelMA) and hyaluronic acid methacryloyl (HAMA) to develop bioinks (namely, GHM bioink) that promote myogenesis. The prepared GHM bioinks were found to offer excellent printability with structural integrity, cytocompatibility, and microporosity. Additionally, MXene NPs within the 3D bioprinted constructs encouraged the differentiation of C2C12 cells into skeletal muscle cells without additional support of myogenic agents. Genetic analysis indicated that representative myogenic markers both for early and late myogenesis were significantly up-regulated. Moreover, animal studies demonstrated that GHM bioinks contributed to enhanced regeneration of skeletal muscle while reducing immune responses in mice models with volumetric muscle loss (VML). Our results suggest that the GHM hydrogel can be exploited to craft a range of strategies for the development of a novel bioink to facilitate skeletal muscle regeneration because these MXene-incorporated composite materials have the potential to promote myogenesis.


Assuntos
Hidrogéis , Nanopartículas , Nitritos , Elementos de Transição , Camundongos , Animais , Hidrogéis/farmacologia , Hidrogéis/química , Gelatina/química , Impressão Tridimensional , Glicosaminoglicanos , Músculo Esquelético , Tecidos Suporte/química , Engenharia Tecidual/métodos
4.
Nat Commun ; 15(1): 2723, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548715

RESUMO

Integration of extracellular signals by neurons is pivotal for brain development, plasticity, and repair. Axon guidance relies on receptor-ligand interactions crosstalking with extracellular matrix components. Semaphorin-5A (Sema5A) is a bifunctional guidance cue exerting attractive and inhibitory effects on neuronal growth through the interaction with heparan sulfate (HS) and chondroitin sulfate (CS) glycosaminoglycans (GAGs), respectively. Sema5A harbors seven thrombospondin type-1 repeats (TSR1-7) important for GAG binding, however the underlying molecular basis and functions in vivo remain enigmatic. Here we dissect the structural basis for Sema5A:GAG specificity and demonstrate the functional significance of this interaction in vivo. Using x-ray crystallography, we reveal a dimeric fold variation for TSR4 that accommodates GAG interactions. TSR4 co-crystal structures identify binding residues validated by site-directed mutagenesis. In vitro and cell-based assays uncover specific GAG epitopes necessary for TSR association. We demonstrate that HS-GAG binding is preferred over CS-GAG and mediates Sema5A oligomerization. In vivo, Sema5A:GAG interactions are necessary for Sema5A function and regulate Plexin-A2 dependent dentate progenitor cell migration. Our study rationalizes Sema5A associated developmental and neurological disorders and provides mechanistic insights into how multifaceted guidance functions of a single transmembrane cue are regulated by proteoglycans.


Assuntos
Glicosaminoglicanos , Semaforinas , Glicosaminoglicanos/metabolismo , Proteoglicanas/metabolismo , Heparitina Sulfato/metabolismo , Movimento Celular , Semaforinas/genética , Semaforinas/metabolismo
5.
Methods Mol Biol ; 2783: 167-176, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38478232

RESUMO

Decellularized human-adipose tissue (hDAT) can serve as an alternative to two-dimensional monolayer culture and current ECM hydrogels due to its unlimited availability and cytocompatibility. A major hurdle in the clinical translation and integration of hDAT and other hydrogels into current in vitro culture processes is adherence to current good manufacturing practices (cGMP). Transferring of innovative technologies, including hydrogels, requires the establishing standardized protocols for quality assurance and quality control (QA/QC) of the material.Integration of basic characterization techniques, including physiochemical characterization, structural/morphological characterization, thermal and mechanical characterization, and biological characterization, in addition to the reduction of batch-to-batch variability and establishment of proper sterilization, storage, and fabrication processes verifies the integrity of the hydrogel. Obatala Sciences has established a characterization protocol that involves a series of assays including the evaluation of gelation properties, protein content, glycosaminoglycan content, soluble collagen content, and DNA content of hDAT.


Assuntos
Matriz Extracelular , Hidrogéis , Humanos , Hidrogéis/química , Matriz Extracelular/metabolismo , Colágeno/metabolismo , Glicosaminoglicanos/metabolismo , Controle de Qualidade , Engenharia Tecidual/métodos
6.
Carbohydr Polym ; 333: 121979, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38494232

RESUMO

Heparan sulfate (HS) is a glycosaminoglycan (GAG) found throughout nature and is involved in a wide range of functions including modulation of cell signalling via sequestration of growth factors. Current consensus is that the specificity of HS motifs for protein binding are individual for each protein. Given the structural complexity of HS the synthesis of libraries of these compounds to probe this is not trivial. Herein we present the synthesis of an HS decamer, the design of which was undertaken rationally from previously published data for HS binding to the growth factor BMP-2. The biological activity of this HS decamer was assessed in vitro, showing that it had the ability to both bind BMP-2 and increase its thermal stability as well as enhancing the bioactivity of BMP-2 in vitro in C2C12 cells. At the same time no undesired anticoagulant effect was observed. This decamer was then analysed in vivo in a rabbit model where higher bone formation, bone mineral density (BMD) and trabecular thickness were observed over an empty defect or collagen implant alone. This indicated that the HS decamer was effective in promoting bone regeneration in vivo.


Assuntos
Glicosaminoglicanos , Heparitina Sulfato , Animais , Coelhos , Heparitina Sulfato/química , Osteogênese , Ligação Proteica , Regeneração Óssea , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo
7.
Int J Mol Sci ; 25(5)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38474135

RESUMO

Nucleotides, glycosaminoglycans, and omega-3 essential fatty acids (O3s) could be used for improving skin health, although their modes of action, alone or in combination, are not yet fully understood. To gain some insight into these mechanisms, we performed two in vitro tests and one in vivo pilot trial. The effects on human dermal fibroblast proliferation and migration were evaluated with the following compounds and combinations: 0.156 mg/mL O3s, 0.0017 mg/mL hyaluronic acid (HA), 0.0004 mg/mL dermatan sulfate (DS), 0.0818 mg/mL nucleotides, and [O3s + HA + DS] and [O3s + HA + DS + nucleotides] at the same concentrations. In both in vitro assays, adding nucleotides to [O3s + HA + DS] provided significant improvements. The resulting combination [O3s + HA + DS + nucleotides] was then tested in vivo in dogs with atopic dermatitis by oral administration of a supplement providing a daily amount of 40 mg/kg nucleotides, 0.9 mg/kg HA, 0.18 mg/kg DS, 53.4 mg/kg EPA, and 7.6 mg/kg DHA. After 30 days, the pruritus visual analog scale (pVAS) score was significantly reduced, and no adverse effects were observed. In conclusion, the combination of nucleotides plus glycosaminoglycans and O3s could serve as a useful therapeutic alternative in skin health applications.


Assuntos
Dermatite Atópica , Doenças do Cão , Ácidos Graxos Ômega-3 , Humanos , Animais , Cães , Dermatite Atópica/tratamento farmacológico , Saccharomyces cerevisiae , Doenças do Cão/tratamento farmacológico , Prurido/tratamento farmacológico , Ácidos Graxos Ômega-3/uso terapêutico , Glicosaminoglicanos/uso terapêutico , Ácido Hialurônico/uso terapêutico , Proliferação de Células , Fibroblastos
8.
Sci Signal ; 17(828): eabl3758, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38502733

RESUMO

CXCL17 is a chemokine principally expressed by mucosal tissues, where it facilitates chemotaxis of monocytes, dendritic cells, and macrophages and has antimicrobial properties. CXCL17 is also implicated in the pathology of inflammatory disorders and progression of several cancers, and its expression is increased during viral infections of the lung. However, the exact role of CXCL17 in health and disease requires further investigation, and there is a need for confirmed molecular targets mediating CXCL17 functional responses. Using a range of bioluminescence resonance energy transfer (BRET)-based assays, here we demonstrated that CXCL17 inhibited CXCR4-mediated signaling and ligand binding. Moreover, CXCL17 interacted with neuropillin-1, a VEGFR2 coreceptor. In addition, we found that CXCL17 only inhibited CXCR4 ligand binding in intact cells and demonstrated that this effect was mimicked by known glycosaminoglycan binders, surfen and protamine sulfate. Disruption of putative GAG binding domains in CXCL17 prevented CXCR4 binding. This indicated that CXCL17 inhibited CXCR4 by a mechanism of action that potentially required the presence of a glycosaminoglycan-containing accessory protein. Together, our results revealed that CXCL17 is an endogenous inhibitor of CXCR4 and represents the next step in our understanding of the function of CXCL17 and regulation of CXCR4 signaling.


Assuntos
Quimiocinas CXC , Glicosaminoglicanos , Quimiocinas CXC/metabolismo , Glicosaminoglicanos/farmacologia , Ligantes , Quimiocinas/metabolismo , Transdução de Sinais , Receptores CXCR4/genética , Quimiocina CXCL12
9.
Mar Drugs ; 22(3)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38535480

RESUMO

Thromboembolic conditions are the most common cause of death in developed countries. Anticoagulant therapy is the treatment of choice, and heparinoids and warfarin are the most adopted drugs. Sulphated polysaccharides extracted from marine organisms have been demonstrated to be effective alternatives, blocking thrombus formation by inhibiting some factors involved in the coagulation cascade. In this study, four acidic glycan fractions from the marine sponge Sarcotragus spinosulus were purified by anion-exchange chromatography, and their anticoagulant properties were investigated through APTT and PT assays and compared with both standard glycosaminoglycans and holothurian sulphated polysaccharides. Moreover, their topographic localization was assessed through histological analysis, and their cytocompatibility was tested on a human fibroblast cell line. A positive correlation between the amount of acid glycans and the inhibitory effect towards both the intrinsic and extrinsic coagulation pathways was observed. The most effective anticoagulant activity was shown by a highly charged fraction, which accounted for almost half (about 40%) of the total hexuronate-containing polysaccharides. Its preliminary structural characterization, performed through infrared spectroscopy and nuclear magnetic resonance, suggested that it may consist of a fucosylated chondroitin sulphate, whose unique structure may be responsible for the anticoagulant activity reported herein for the first time.


Assuntos
Poríferos , Humanos , Animais , Polissacarídeos , Glicosaminoglicanos , Anticoagulantes , Coagulação Sanguínea , Sulfatos
10.
Carbohydr Polym ; 332: 121905, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38431412

RESUMO

Glycosaminoglycans (GAGs), as a class of biopolymers, play pivotal roles in various biological metabolisms such as cell signaling, tissue development, cell apoptosis, immune modulation, and growth factor activity. They are mainly present in the colon in free forms, which are essential for maintaining the host's health by regulating the colonization and proliferation of gut microbiota. Therefore, it is important to explain the specific members of the gut microbiota for GAGs' degradation and their enzymatic machinery in vivo. This review provides an outline of GAGs-utilizing entities in the Bacteroides, highlighting their polysaccharide utilization loci (PULs) and the enzymatic machinery involved in chondroitin sulfate (CS) and heparin (Hep)/heparan sulfate (HS). While there are some variations in GAGs' degradation among different genera, we analyze the reputed GAGs' utilization clusters in lactic acid bacteria (LAB), based on recent studies on GAGs' degradation. The enzymatic machinery involved in Hep/HS and CS metabolism within LAB is also discussed. Thus, to elucidate the precise mechanisms utilizing GAGs by diverse gut microbiota will augment our understanding of their effects on human health and contribute to potential therapeutic strategies for diseases.


Assuntos
Microbioma Gastrointestinal , Lactobacillales , Humanos , Glicosaminoglicanos/metabolismo , Bacteroides/metabolismo , Lactobacillales/metabolismo , Heparina , Heparitina Sulfato
11.
Artigo em Chinês | MEDLINE | ID: mdl-38433691

RESUMO

Objective:To analyze the characteristics of otorhinolaryngological clinical manifestations in children with Mucopolysaccharide(MPS) type Ⅰ and type II in order to improve the knowledge of otorhinolaryngologists about this disease. Methods:Clinical data related to 55 children with MPS type Ⅰ and type II were retrospectively analyzed to investigate the clinical manifestations of MPS in ENT. Results:All 40 patients(72.72%) with MPS had at least one ENT symptom during the course of the disease, with 95% of them having an ENT symptom prior to the diagnosis of MPS; upper airway obstruction was the most common ENT symptom(34, 85.00%), followed by recurrent upper respiratory tract infections(23, 57.50%), and lastly, hearing loss(11, 27.50%); all 26 patients had undergone at least one surgical procedure, of which 15(57.69%) had undergone ENT surgery, and all of these patients underwent ENT surgery before diagnosis. The most common ENT surgery was adenoidectomy. Conclusion:Early clinical manifestations of MPS patients are atypical, but the early and prevalent appearance of otolaryngologic symptoms and increased awareness of the disease among otolaryngologists has a positive impact on the prognosis of MPS.


Assuntos
Surdez , Doenças Nasais , Criança , Humanos , Estudos Retrospectivos , Adenoidectomia , Glicosaminoglicanos
12.
Glycobiology ; 34(5)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38438145

RESUMO

This review delves into the roles of glycosaminoglycans (GAGs), integral components of proteoglycans, in tooth development. Proteoglycans consist of a core protein linked to GAG chains, comprised of repeating disaccharide units. GAGs are classified into several types, such as hyaluronic acid, heparan sulfate, chondroitin sulfate, dermatan sulfate, and keratan sulfate. Functioning as critical macromolecular components within the dental basement membrane, these GAGs facilitate cell adhesion and aggregation, and play key roles in regulating cell proliferation and differentiation, thereby significantly influencing tooth morphogenesis. Notably, our recent research has identified the hyaluronan-degrading enzyme Transmembrane protein 2 (Tmem2) and we have conducted functional analyses using mouse models. These studies have unveiled the essential role of Tmem2-mediated hyaluronan degradation and its involvement in hyaluronan-mediated cell adhesion during tooth formation. This review provides a comprehensive summary of the current understanding of GAG functions in tooth development, integrating insights from recent research, and discusses future directions in this field.


Assuntos
Glicosaminoglicanos , Ácido Hialurônico , Camundongos , Animais , Glicosaminoglicanos/metabolismo , Proteoglicanas/metabolismo , Sulfato de Ceratano/metabolismo , Sulfatos de Condroitina/metabolismo , Heparitina Sulfato/metabolismo , Odontogênese , Dermatan Sulfato
13.
Cell Signal ; 118: 111149, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38522808

RESUMO

G protein-coupled receptors (GPCR) and glycosaminoglycans (GAGs) are two essential components of the cell surface that regulate physiological processes in the body. GPCRs are the most extensive family of transmembrane receptors that control cellular responses to extracellular stimuli, while GAGs are polysaccharides that contribute to the function of the extracellular matrix (ECM). Due to their proximity to the plasma membrane, GAGs participate in signal transduction by interacting with various extracellular molecules and cell surface receptors. GAGs can directly interact with certain GPCRs or their ligands (chemokines, peptide hormones and neuropeptides, structural proteins, and enzymes) from the glutamate receptor family, the rhodopsin receptor family, the adhesion receptor family, and the secretin receptor family. These interactions have recently become an emerging topic, providing a new avenue for understanding how GPCR signaling is regulated. This review discusses our current state of knowledge about the role of GAGs in GPCR signaling and function.


Assuntos
Glicosaminoglicanos , Receptores Acoplados a Proteínas G , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais/fisiologia , Membrana Celular/metabolismo , Rodopsina/metabolismo
14.
Int J Biol Macromol ; 264(Pt 2): 130743, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38462098

RESUMO

Heparin, a member of the glycosaminoglycan family, is renowned as the most negatively charged biomolecule discovered within the realm of human biology. This polysaccharide serves a vital role as a regulator for various proteins, cells, and tissues within the human body, positioning itself as a pivotal macromolecule of significance. The domain of biology has witnessed substantial interest in the intricate design of heparin and its derivatives, particularly focusing on heparin-based polymers and hydrogels. This intrigue spans a wide spectrum of applications, encompassing diverse areas such as protein adsorption, anticoagulant properties, controlled drug release, development of implants, stent innovation, enhancement of blood compatibility, acceleration of wound healing, and pioneering strides in tissue engineering. This comprehensive overview delves into a multitude of developed heparin conjugates, employing various methods, and explores their functions in both the biomedicine and electronics fields. The efficacy of materials derived from heparin is also thoroughly investigated, encompassing considerations such as thrombogenicity, drug release kinetics, affinity for growth factors (GFs), biocompatibility, and electrochemical analyses. We firmly believe that by redirecting focus towards research and advancements in heparin-related polymers/hydrogels, this study will ignite further research and accelerate potential breakthroughs in this promising and evolving field of discovery.


Assuntos
Anticoagulantes , Heparina , Humanos , Heparina/química , Anticoagulantes/química , Glicosaminoglicanos , Hidrogéis/química , Polímeros/química , Engenharia Tecidual/métodos , Materiais Biocompatíveis/química
15.
Viruses ; 16(2)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38400013

RESUMO

Middle East respiratory syndrome coronavirus (MERS-CoV) is a zoonotic virus with high contagion and mortality rates. Heparan sulfate proteoglycans (HSPGs) are ubiquitously expressed on the surface of mammalian cells. Owing to its high negatively charged property, heparan sulfate (HS) on the surface of host cells is used by many viruses as cofactor to facilitate viral attachment and initiate cellular entry. Therefore, inhibition of the interaction between viruses and HS could be a promising target to inhibit viral infection. In the current study, the interaction between the receptor-binding domain (RBD) of MERS-CoV and heparin was exploited to assess the inhibitory activity of various sulfated glycans such as glycosaminoglycans, marine-sourced glycans (sulfated fucans, fucosylated chondroitin sulfates, fucoidans, and rhamnan sulfate), pentosan polysulfate, and mucopolysaccharide using Surface Plasmon Resonance. We believe this study provides valuable insights for the development of sulfated glycan-based inhibitors as potential antiviral agents.


Assuntos
Heparina , Coronavírus da Síndrome Respiratória do Oriente Médio , Animais , Heparina/farmacologia , Coronavírus da Síndrome Respiratória do Oriente Médio/metabolismo , Sulfatos/química , Glicosaminoglicanos/metabolismo , Heparitina Sulfato/metabolismo , Mamíferos
16.
Int J Biol Macromol ; 261(Pt 2): 129934, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38311145

RESUMO

Hair follicle (HF) tissue engineering is promising for hair loss treatment especially for androgenetic alopecia. Physiologically, the initiation of HF morphogenesis relies on the interactions between hair germ mesenchymal and epithelial layers. To simulate this intricate process, in this study, a co-flowing microfluidic-assisted technology was developed to produce dual aqueous microdroplets capturing growth factors and double-layer cells for subsequent use in hair regeneration. Microspheres, called G/HAD, were generated using glycosaminoglycan-based photo-crosslinkable biological macromolecule (HAD) shells and gelatin methacrylate (GelMA) cores to enclose mesenchymal cells (MSCs) and mouse epidermal cells (EPCs). The findings indicated that the glycosaminoglycan-based HAD shells display thermodynamic incompatibility with GelMA cores, resulting in the aqueous phase separation of G/HAD cell spheres. These G/HAD microspheres exhibited favorable characteristics, including sustained growth factor release and wet adhesion properties. After transplantation into the dorsal skin of BALB/c nude mice, G/HAD cell microspheres efficiently induced the regeneration of HFs. This approach enables the mass production of approximately 250 dual-layer microspheres per minute. Thus, this dual-layer microsphere fabrication method holds great potential in improving current hair regeneration techniques and can also be combined with other tissue engineering techniques for various regenerative purposes.


Assuntos
Gelatina , Glicosaminoglicanos , Camundongos , Animais , Gelatina/metabolismo , Microesferas , Glicosaminoglicanos/metabolismo , Metacrilatos , Camundongos Nus , Biomimética , Cabelo , Folículo Piloso , Termodinâmica
17.
Tissue Eng Part A ; 30(7-8): 357-366, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38318848

RESUMO

Subchondral drilling (SD), a bone marrow stimulation technique, is used to repair cartilage lesions that lack regenerative potential. Cartilage repair outcomes upon SD are typically fibrocartilaginous in nature with inferior functionality. The lack of cues to foster the chondrogenic differentiation of egressed mesenchymal stromal cells upon SD can be attributed for the poor outcomes. Continuous low-intensity ultrasound (cLIUS) at 3.8 MHz is proposed as a treatment modality for improving cartilage repair outcomes upon marrow stimulation. Bilateral defects were created by SD on the femoral medial condyle of female New Zealand white rabbits (n = 12), and the left joint received cLIUS treatment (3.8 MHz, 3.5 Vpp, 8 min/application/day) and the contralateral right joint served as the control. On day 7 postsurgery, synovial fluid was aspirated, and the cytokine levels were assessed by Quantibody™ assay. Rabbits were euthanized at 8 weeks and outcomes were assessed macroscopically and histologically. Defect areas in the right joints exhibited boundaries, incomplete fill, irregular cartilage surfaces, loss of glycosaminoglycan (GAG), and absence of chondrocytes. In contrast, the repaired defect area in the joints that received cLIUS showed complete fill, positive staining for GAG with rounded chondrocyte morphology, COL2A1 staining, and columnar organization. Synovial fluid collected from cLIUS-treated left knee joints had lower levels of IL1, TNFα, and IFNγ when compared to untreated right knee joints, alluding to the potential of cLIUS to mitigate early inflammation. Further at 8 weeks, left knee joints (n = 12) consistently scored higher on the O'Driscoll scale, with a higher percent hyaline cartilage score. No adverse impact on bone or change in the joint space was noted. Upon a single exposure of cLIUS to TNFα-treated cells, nuclear localization of pNFκB and SOX9 was visualized by double immunofluorescence and the expression of markers associated with the NFκB pathway was assayed by quantitative real-time polymerase chain reaction. cLIUS extends its chondroprotective effects by titrating pNFκB levels, preventing its nuclear translocation, while maintaining the expression of SOX9, the collagen II transcription factor. Our combined results demonstrate that healing of chondral defects treated with marrow stimulation by SD can be accelerated by employing cLIUS regimen that possesses chondroinductive and chondroprotective properties. Impact statement Repair of cartilage represents an unsolved biomedical burden. In vitro, continuous low-intensity ultrasound (cLIUS) has been demonstrated to possess chondroinductive and chondroprotective potential. To our best knowledge, the use of cLIUS to improve cartilage repair outcomes upon marrow stimulation, in vivo, has not been reported and our work reported here fills that gap. Our results demonstrated enhanced cartilage repair outcomes under cLIUS (3.8 MHz) in a rabbit model of subchondral injury by subchondral drilling. Enhanced repair stemmed from mesenchymal stem cell differentiation in vivo and the subsequent synthesis of articular cartilage-specific matrix.


Assuntos
Cartilagem Articular , Fator de Necrose Tumoral alfa , Coelhos , Feminino , Animais , Ultrassonografia , Colágeno/metabolismo , Regulação da Expressão Gênica , Glicosaminoglicanos/metabolismo
18.
J Biomater Sci Polym Ed ; 35(6): 880-897, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38346177

RESUMO

The aim of the in vitro study was to asses the effect of hyaluronate in conjunction with bovine derived xenografts on the viability, proliferation on day 4, 7 and 10, expression of early osteogenic differentiation marker Alkaline phosphatase on day 14 and 21, collagen, calcium deposition on day 14, 21 and 28 and cellular characteristics, as assessed through live cell image analysis, confocal laser scanning microscopy and scanning electron microscopy, in primary human osteoblasts compared to three bovine xenografts without hyaluronate. All experiments were performed in triplicates. Data were compared between groups and timepoints using one-way analysis of variance (ANOVA). Bonferroni post hoc test were further used for multiple comparison between groups (p < .05) An increase in cell viability (p < .05) and enhanced ALP activity was observed in all xenografts. Specimens containing hyaluronate showed a highest significant difference (23755 ± 29953, p < .0001). The highest levels of calcium (1.60 ± 0.30) and collagen (1.92 ± 0.09, p < .0001) deposition were also observed with hyaluronate loaded groups. The osteoblasts were well attached and spread on all xenograft groups. However, a higher number of cells were observed with hyaluronate functionalized xenograft (76.27 ± 15.11, (p < .0001) in live cell image analysis and they migrated towards the graft boundaries. The biofunctionalization of xenografts with hyaluronate improves their in vitro performance on human osteoblasts. This suggests that hyaluronate might be able to improve the bone regeneration when using such xenografts.


Assuntos
Cálcio , Osteogênese , Humanos , Animais , Bovinos , Osteogênese/fisiologia , Xenoenxertos , Cálcio/metabolismo , Diferenciação Celular , Osteoblastos , Colágeno/farmacologia , Glicosaminoglicanos , Proliferação de Células , Fosfatase Alcalina/metabolismo
19.
Angew Chem Int Ed Engl ; 63(13): e202316791, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38308859

RESUMO

Heparin and heparan sulfate (HS) are naturally occurring mammalian glycosaminoglycans, and their synthetic and semi-synthetic mimetics have attracted significant interest as potential therapeutics. However, understanding the mechanism of action by which HS, heparin, and HS mimetics have a biological effect is difficult due to their highly charged nature, broad protein interactomes, and variable structures. To address this, a library of novel single-entity dendritic mimetics conjugated to BODIPY, Fluorine-19 (19 F), and biotin was synthesized for imaging and localization studies. The novel dendritic scaffold allowed for the conjugation of labeling moieties without reducing the number of sulfated capping groups, thereby better mimicking the multivalent nature of HS-protein interactions. The 19 F labeled mimetics were assessed in phantom studies and were detected at concentrations as low as 5 mM. Flow cytometric studies using a fluorescently labeled mimetic showed that the compound associated with immune cells from tumors more readily than splenic counterparts and was directed to endosomal-lysosomal compartments within immune cells and cancer cells. Furthermore, the fluorescently labeled mimetic entered the central nervous system and was detectable in brain-infiltrating immune cells 24 hours after treatment. Here, we report the enabling methodology for rapidly preparing various labeled HS mimetics and molecular probes with diverse potential therapeutic applications.


Assuntos
Biotina , Compostos de Boro , Heparitina Sulfato , Animais , Heparitina Sulfato/química , Glicosaminoglicanos/metabolismo , Heparina/metabolismo , Mamíferos/metabolismo
20.
Int J Biol Macromol ; 262(Pt 1): 129969, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38325688

RESUMO

Chondroitin sulfate (CS), dermatan sulfate (DS), and CS/DS hybrid chains are natural complex glycosaminoglycans with high structural diversity and widely distributed in marine organisms, such as fish, shrimp, starfish, and sea cucumber. Numerous CS, DS, and CS/DS hybrid chains with various structures and activities have been obtained from marine animals and have received extensive attention. However, only a few of these hybrid chains have been well-characterized and commercially developed. This review presents information on the extraction, purification, structural characterization, biological activities, potential action mechanisms, and structure-activity relationships of marine CS, DS, and CS/DS hybrid chains. We also discuss the challenges and perspectives in the research of CS, DS, and CS/DS hybrid chains. This review may provide a useful reference for the further investigation, development, and application of CS, DS, and CS/DS hybrid chains in the fields of functional foods and therapeutic agents.


Assuntos
Sulfatos de Condroitina , Dermatan Sulfato , Animais , Sulfatos de Condroitina/farmacologia , Sulfatos de Condroitina/química , Dermatan Sulfato/química , Alimento Funcional , Glicosaminoglicanos/química
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