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1.
J Biomed Mater Res A ; 111(1): 45-59, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36054528

RESUMO

Titanium is widely used in bone prostheses due to its excellent biocompatibility and osseointegration capacity. To understand the effect of sandblasted acid-etched (SAE) Ti implants on the biological responses of human osteoblast (HOb), their proteomic profiles were analyzed using nLC-MS/MS. The cells were cultured with the implant materials, and 2544 distinct proteins were detected in samples taken after 1, 3, and 7 days. Comparative analyses of proteomic data were performed using Perseus software. The expression of proteins related to EIF2, mTOR, insulin-secretion and IGF pathways showed marked differences in cells grown with SAE-Ti in comparison with cells cultured without Ti. Moreover, the proteomic profiles obtained with SAE-Ti were compared over time. The affected proteins were related to adhesion, immunity, oxidative stress, coagulation, angiogenesis, osteogenesis, and extracellular matrix formation functions. The proliferation, mineralization and osteogenic gene expression in HObs cultured with SAE-Ti were characterized in vitro. The results showed that the osteoblasts exposed to this material increase their mineralization rate and expression of COLI, RUNX2, SP7, CTNNB1, CAD13, IGF2, MAPK2, and mTOR. Overall, the observed proteomic profiles can explain the SAE-Ti osteogenic properties, widening our knowledge of key signaling pathways taking part in the early stages of the osseointegration process in this type of implantations.


Assuntos
Proteômica , Titânio , Humanos , Titânio/farmacologia , Titânio/metabolismo , Espectrometria de Massas em Tandem , Propriedades de Superfície , Osteoblastos , Osseointegração , Osteogênese , Próteses e Implantes , Serina-Treonina Quinases TOR
2.
Methods Mol Biol ; 2582: 255-268, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36370355

RESUMO

Although two-dimensional (2D) cultures from bone lineage cells are often used, it is well-known that this culture system is completely different from the in vivo bone matrix environment. In this paper, we describe a 3D culture method using both the mouse osteocytic cell line, MLO-Y4, and an osteocyte-enriched population of the cells isolated from mice. These cells are embedded in collagen gel with recombinant cellular communication network (CCN) factor proteins; then, osteoblasts or osteoclasts are inoculated and cultured on the collagen gel. Because this method mimics the in vitro bone matrix environment, it is useful for understanding the detailed mechanism of actions of CCN proteins in the bone matrix.


Assuntos
Osteoblastos , Osteócitos , Camundongos , Animais , Diferenciação Celular , Osteoblastos/metabolismo , Remodelação Óssea , Colágeno/metabolismo , Bioensaio
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 285: 121862, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36122465

RESUMO

In response to the growing need for development of modern biomaterials for applications in regenerative medicine strategies, the research presented here investigated the biological potential of two types of polymer nanocomposites. Graphene oxide (GO) and partially reduced graphene oxide (rGO) were incorporated into a poly(ε-caprolactone) (PCL) matrix, creating PCL/GO and PCL/rGO nanocomposites in the form of membranes. Proliferation of osteoblast-like cells (human U-2 OS cell line) on the surface of the studied materials confirmed their biological activity. Fluorescence microscopy was able to distinguish the different patterns of interaction between cells (depending on the type of material) after 15 days of the test run. Raman micro-spectroscopy and two-dimensional correlation spectroscopy (2D-COS) applied to Raman spectra distinguished the nature of cell-material interactions after only 8 days. Combination of these two techniques (Raman micro-spectroscopy and 2D-COS analysis) facilitated identification of a much more complex cellular response (especially from proteins) on the surface of PCL/GO. The presented approach can be regarded as a method for early study of the bioactivity of membrane materials.


Assuntos
Grafite , Humanos , Grafite/farmacologia , Grafite/química , Poliésteres/química , Polímeros , Osteoblastos , Análise Espectral Raman
4.
Elife ; 112022 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-36342465

RESUMO

Pathological obesity and its complications are associated with an increased propensity for bone fractures. Humans with certain genetic polymorphisms at the kinase suppressor of ras2 (KSR2) locus develop severe early-onset obesity and type 2 diabetes. Both conditions are phenocopied in mice with Ksr2 deleted, but whether this affects bone health remains unknown. Here we studied the bones of global Ksr2 null mice and found that Ksr2 negatively regulates femoral, but not vertebral, bone mass in two genetic backgrounds, while the paralogous gene, Ksr1, was dispensable for bone homeostasis. Mechanistically, KSR2 regulates bone formation by influencing adipocyte differentiation at the expense of osteoblasts in the bone marrow. Compared with Ksr2's known role as a regulator of feeding by its function in the hypothalamus, pair-feeding and osteoblast-specific conditional deletion of Ksr2 reveals that Ksr2 can regulate bone formation autonomously. Despite the gains in appendicular bone mass observed in the absence of Ksr2, bone strength, as well as fracture healing response, remains compromised in these mice. This study highlights the interrelationship between adiposity and bone health and provides mechanistic insights into how Ksr2, an adiposity and diabetic gene, regulates bone metabolism.


Our bones are living tissues which constantly reshape and renew themselves. This ability relies on stem cells present in the marrow cavity, which can mature into the various types of cells needed to produce new bone material, marrow fat, or other components. Obesity and associated conditions such as type 2 diabetes are often linked to harmful changes in the skeleton. In particular, these metabolic conditions are associated with weight-bearing bones becoming more prone to facture and healing poorly. Mice genetically modified to model obesity and diabetes could help researchers to study exactly how these conditions ­ and the genetic changes that underlie them ­ impact bone health. Gomez et al. aimed to address this question by focusing on KSR2, a gene involved in energy consumption and feeding behavior. Children who carry certain KSR2 mutations are prone to obesity and type 2 diabetes; mice lacking the gene also develop these conditions due to uncontrolled eating. Closely examining mutant mice in which Ksr2 had been deactivated in every cell revealed that the weight-bearing bones of these animals were also more likely to break, and the fractures then healed more slowly. This was the case even though these bones had higher mass and less marrow fat compared to healthy mice. Non-weight bearing bones (such as the spine) did not exhibit these changes. Further experiments revealed that, when expressed normally in the skeleton, Ksr2 skews the stem cell maturation process towards marrow fat cells instead of bone-creating cells. This suggests a new role for Ksr2, which therefore seems to independently regulate both feeding behavior and bone health. In addition, the work by Gomez et al. demonstrate that Ksr2 mutant mice could be a useful model to better understand how obesity and diabetes affect human bones, and to potentially develop new therapies.


Assuntos
Adiposidade , Medula Óssea , Osso Esponjoso , Animais , Humanos , Camundongos , Adiposidade/genética , Medula Óssea/metabolismo , Osso Esponjoso/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Camundongos Knockout , Obesidade/metabolismo , Osteoblastos/metabolismo , Proteínas Serina-Treonina Quinases
5.
Proc Natl Acad Sci U S A ; 119(45): e2212178119, 2022 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-36322718

RESUMO

Citrate is a critical metabolic substrate and key regulator of energy metabolism in mammalian cells. It has been known for decades that the skeleton contains most (>85%) of the body's citrate, but the question of why and how this metabolite should be partitioned in bone has received singularly little attention. Here, we show that osteoblasts use a specialized metabolic pathway to regulate uptake, endogenous production, and the deposition of citrate into bone. Osteoblasts express high levels of the membranous Na+-dependent citrate transporter solute carrier family 13 member 5 (Slc13a5) gene. Inhibition or genetic disruption of Slc13a5 reduced osteogenic citrate uptake and disrupted mineral nodule formation. Bones from mice lacking Slc13a5 globally, or selectively in osteoblasts, showed equivalent reductions in cortical thickness, with similarly compromised mechanical strength. Surprisingly, citrate content in mineral from Slc13a5-/- osteoblasts was increased fourfold relative to controls, suggesting the engagement of compensatory mechanisms to augment endogenous citrate production. Indeed, through the coordinated functioning of the apical membrane citrate transporter SLC13A5 and a mitochondrial zinc transporter protein (ZIP1; encoded by Slc39a1), a mediator of citrate efflux from the tricarboxylic acid cycle, SLC13A5 mediates citrate entry from blood and its activity exerts homeostatic control of cytoplasmic citrate. Intriguingly, Slc13a5-deficient mice also exhibited defective tooth enamel and dentin formation, a clinical feature, which we show is recapitulated in primary teeth from children with SLC13A5 mutations. Together, our results reveal the components of an osteoblast metabolic pathway, which affects bone strength by regulating citrate deposition into mineral hydroxyapatite.


Assuntos
Ácido Cítrico , Simportadores , Animais , Camundongos , Ácido Cítrico/metabolismo , Simportadores/metabolismo , Durapatita/metabolismo , Citratos , Ciclo do Ácido Cítrico , Osteoblastos/metabolismo , Mamíferos/metabolismo , Transportadores de Ácidos Dicarboxílicos/metabolismo
6.
Cells ; 11(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36359752

RESUMO

The culture of osteoblasts (OB) of human origin is a useful experimental model in studying bone biology, osteogenic differentiation, functions of bone proteins, oncological processes in bone tissue, testing drugs against bone desires, and many other fields. The purpose of the present study is to share a workflow that has established the conditions to efficiently isolate and grow OB cells obtained from surgically removed bones from human donors. The protocol described here also shows how to determine cell phenotype. Here we provide characteristics of cells isolated by this protocol that might help researchers to decide if such OB are suitable for the purposes of their study. Osteoblasts isolated from collagenase-treated explants of adult bones are able to proliferate and keep their phenotype in culture. OB cells have high synthetic properties. They express osteomarkers, such as RUNX2, osteocalcin, BMP2, and osteopontin both in control conditions and in an osteogenic medium that could be estimated by qPCR and immunocytochemical staining and by Western blotting. Induction of osteogenic differentiation does not dramatically influence the synthetic properties of OB cells, while the cells gain the ability to extracellular mineralization only in an osteogenic medium.


Assuntos
Osteoblastos , Osteogênese , Humanos , Osteogênese/genética , Osteoblastos/metabolismo , Diferenciação Celular , Osteocalcina/metabolismo , Osso e Ossos/metabolismo
7.
Front Endocrinol (Lausanne) ; 13: 940624, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36353240

RESUMO

This study aimed to evaluate the osteotoxicity of polychlorinated biphenyls in murine osteoblastic MC3T3-E1 cells, and to explore the underlying mechanism focused on oxidative stress. The cells were exposed to Aroclor 1254 at concentrations of 2.5-20 µmol/L, and then cell viability, oxidative stress, intracellular calcium concentration, osteocalcin content, and calcium nodules formation were measured. Aroclor 1254 reduced cell viability and induced overproduction of intracellular reactive oxygen species in a dose-dependent manner. Activity of superoxide dismutase was decreased, and malondialdehyde content was promoted after exposure. Moreover, inhibitory effects of Aroclor 1254 on calcium metabolism and mineralization of osteoblasts were observed, as indicated by reduction of the intracellular calcium concentration, osteocalcin content, and modules formation rate. The decreased expression of osteocalcin, alkaline phosphatase, bone sialoprotein, and transient receptor potential vanilloid 6 further confirmed the impairment of Aroclor 1254 on calcium homeostasis and osteoblast differentiation. Addition of the antioxidant N-acetyl-L-cysteine partially restored the inhibitory effects on calcium metabolism and mineralization. In general, Aroclor 1254 exposure reduces calcium homeostasis, osteoblast differentiation and bone formation, and oxidative stress plays a vital role in the underlying molecular mechanism of osteotoxicity.


Assuntos
Cálcio , Osteogênese , Camundongos , Animais , /metabolismo , Osteocalcina/metabolismo , Cálcio/metabolismo , Osteoblastos , Estresse Oxidativo
8.
Biomed Res Int ; 2022: 9668610, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36330460

RESUMO

Orthodontic tooth movement (OTM) is a tissue remodeling process based on orthodontic force loading. Compressed periodontal tissues have a complicated aseptic inflammatory cascade, which are considered the initial factor of alveolar bone remodeling. Since skeletal and immune systems shared a wide variety of molecules, osteoimmunology has been generally accepted as an interdisciplinary field to investigate their interactions. Unsurprisingly, OTM is considered a good mirror of osteoimmunology since it involves immune reaction and bone remolding. In fact, besides bone remodeling, OTM involves cementum resorption, soft tissue remodeling, orthodontic pain, and relapse, all correlated with immune cells and/or immunologically active substance. The aim of this paper is to review the interaction of immune system with orthodontic tooth movement, which helps gain insights into mechanisms of OTM and search novel method to short treatment period and control complications.


Assuntos
Osteoclastos , Técnicas de Movimentação Dentária , Remodelação Óssea , Osteoblastos , Sistema Imunitário
9.
Acta Chir Orthop Traumatol Cech ; 89(5): 370-375, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36322038

RESUMO

PURPOSE OF THE STUDY Nitinol (NiTi) is a biomaterial widely used in medicine based on super-elastic and shape memory properties. miR-124 has a key role in inflammatory process, osteoblasts differentiation, and mineralization. The aim of study was evaluating the differences in gene expression of miR-124 of human physiological osteoblasts (HOB) and human osteoarthritic osteoblasts (OSBA) as a response to NiTi alloy in different heat treatments. MATERIAL AND METHODS The cells were cultivated with NiTi discs with/without addition of bacterial lipopolysaccharide (LPS) for 72 hours. MicroRNAs were isolated, underwent reverse transcription and were analyzed by RT-PCR. RESULTS As a response to LPS, HOB overexpressed miR-124, while in OSBA expression change did not occur. Overexpression was also observed in both cell lines as a response to hydrogen and helium treated NiTi discs. HOB expressed significantly higher amount of miR-124 than OSBA as a response to hydrogen treatment of NiTi discs. In addition, hydrogen treatment caused significantly higher expression in HOB than LPS. The combination of NiTi disc and LPS treatment in HOB didn't cause any expression changes. Comparing to LPS-only treatment, the expression in HOB with combination of LPS and alloy was significantly lower. In OSBA, the expression was increased by the combination of LPS and hydrogen disc, in case of helium disc, the expression was decreased. CONCLUSIONS In conclusion, human physiological and osteoarthritic osteoblasts respond to NiTi alloy with both surface (hydrogen and helium atmosphere) treatment by overexpression of miR-124. The effect of LPS as inflammatory modulator suggests the presence of an "anti-inflammatory preconditioning" in osteoarthritic osteoblasts, as physiological osteoblasts overexpression was significantly higher. Key words: nitinol, osteoblast, miR-124, lipopolysaccharide.


Assuntos
Lipopolissacarídeos , MicroRNAs , Humanos , Ligas/metabolismo , Ligas/farmacologia , Hélio/metabolismo , Hélio/farmacologia , Hidrogênio/metabolismo , Hidrogênio/farmacologia , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , MicroRNAs/farmacologia , Osteoblastos/metabolismo , Titânio , Osteoartrite/genética
10.
Int J Mol Sci ; 23(21)2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36361965

RESUMO

Mineralization-competent cells like osteoblasts and chondrocytes release matrix vesicles (MVs) which accumulate Ca2+ and Pi, creating an optimal environment for apatite formation. The mineralization process requires the involvement of proteins, such as annexins (Anx) and tissue-nonspecific alkaline phosphatase (TNAP), as well as low molecular-weight compounds. Apigenin, a flavonoid compound, has been reported to affect bone metabolism, but there are doubts about its mechanism of action under physiological and pathological conditions. In this report, apigenin potency to modulate annexin A6 (AnxA6)- and TNAP-mediated osteoblast mineralization was explored using three cell lines: human fetal osteoblastic hFOB 1.19, human osteosarcoma Saos-2, and human coronary artery smooth muscle cells HCASMC. We compared the mineralization competence, the morphology and composition of minerals, and the protein distribution in control and apigenin-treated cells and vesicles. The mineralization ability was monitored by AR-S/CPC analysis, and TNAP activity was determined by ELISA assay. Apigenin affected the mineral structure and modulated TNAP activity depending on the concentration. We also observed increased mineralization in Saos-2 cells. Based on TEM-EDX, we found that apigenin influenced the mineral composition. This flavonoid also disturbed the intracellular distribution of AnxA6 and TNAP, especially blocking AnxA6 aggregation and TNAP attachment to the membrane, as examined by FM analysis of cells and TEM-gold analysis of vesicles. In summary, apigenin modulates the mineralization process by regulating AnxA6 and TNAP, as well as through various effects on normal and cancer bone tissues or atherosclerotic soft tissue.


Assuntos
Neoplasias Ósseas , Calcinose , Humanos , Fosfatase Alcalina/metabolismo , Anexina A6/metabolismo , Calcificação Fisiológica/fisiologia , Apigenina/farmacologia , Apigenina/metabolismo , Osteoblastos/metabolismo , Calcinose/metabolismo , Minerais/metabolismo , Neoplasias Ósseas/metabolismo
11.
Front Biosci (Landmark Ed) ; 27(10): 295, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36336853

RESUMO

BACKGROUND: Recently, single-cell RNA sequencing (scRNA-seq) technology was increasingly used to study transcriptomics at a single-cell resolution, scRNA-seq analysis was complicated by the "dropout", where the data only captures a small fraction of the transcriptome. This phenomenon can lead to the fact that the actual expressed transcript may not be detected. We previously performed osteoblast subtypes classification and dissection on freshly isolated human osteoblasts. MATERIALS AND METHODS: Here, we used the scImpute method to impute the missing values of dropout genes from a scRNA-seq dataset generated on freshly isolated human osteoblasts. RESULTS: Based on the imputed gene expression patterns, we discovered three new osteoblast subtypes. Specifically, these newfound osteoblast subtypes are osteoblast progenitors, and two undetermined osteoblasts. Osteoblast progenitors showed significantly high expression of proliferation related genes (FOS, JUN, JUNB and JUND). Analysis of each subtype showed that in addition to bone formation, these undetermined osteoblasts may involve osteoclast and adipocyte differentiation and have the potential function of regulate immune activation. CONCLUSIONS: Our findings provided a new perspective for studying the osteoblast heterogeneity and potential biological functions of these freshly isolated human osteoblasts at the single-cell level, which provides further insight into osteoblasts subtypes under various (pathological) physiological conditions.


Assuntos
Osteoblastos , Transcriptoma , Humanos , RNA-Seq , Osteoblastos/metabolismo , Diferenciação Celular/genética , Osteogênese/genética , Perfilação da Expressão Gênica
12.
Int J Mol Sci ; 23(21)2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36362086

RESUMO

RUNX proteins, such as RUNX2, regulate the proliferation and differentiation of chondrocytes and osteoblasts. Haploinsufficiency of RUNX2 causes cleidocranial dysplasia, but a detailed analysis of Runx2+/- mice has not been reported. Furthermore, CBFB is required for the stability and DNA binding of RUNX family proteins. CBFB has two isoforms, and CBFB2 plays a major role in skeletal development. The calvaria, femurs, vertebrae and ribs in Cbfb2-/- mice were analyzed after birth, and compared with those in Runx2+/- mice. Calvarial development was impaired in Runx2+/- mice but mildly delayed in Cbfb2-/- mice. In femurs, the cortical bone but not trabecular bone was reduced in Cbfb2-/- mice, whereas both the trabecular and cortical bone were reduced in Runx2+/- mice. The trabecular bone in vertebrae increased in Cbfb2-/- mice but not in Runx2+/- mice. Rib development was impaired in Cbfb2-/- mice but not in Runx2+/- mice. These differences were likely caused by differences in the indispensability of CBFB and RUNX2, the balance of bone formation and resorption, or the number and maturation stage of osteoblasts. Thus, different amounts of CBFB and RUNX2 were required among the bone tissues for proper bone development and maintenance.


Assuntos
Subunidade alfa 1 de Fator de Ligação ao Core , Osteoblastos , Animais , Camundongos , Diferenciação Celular/genética , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Subunidades alfa de Fatores de Ligação ao Core/metabolismo , Osteoblastos/metabolismo , Osteogênese/genética , Costelas/metabolismo , Crânio/metabolismo , Coluna Vertebral/metabolismo
13.
Int J Oral Sci ; 14(1): 53, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36376275

RESUMO

Bone regeneration remains a great clinical challenge. Low intensity near-infrared (NIR) light showed strong potential to promote tissue regeneration, offering a promising strategy for bone defect regeneration. However, the effect and underlying mechanism of NIR on bone regeneration remain unclear. We demonstrated that bone regeneration in the rat skull defect model was significantly accelerated with low-intensity NIR stimulation. In vitro studies showed that NIR stimulation could promote the osteoblast differentiation in bone mesenchymal stem cells (BMSCs) and MC3T3-E1 cells, which was associated with increased ubiquitination of the core circadian clock protein Cryptochrome 1 (CRY1) in the nucleus. We found that the reduction of CRY1 induced by NIR light activated the bone morphogenetic protein (BMP) signaling pathways, promoting SMAD1/5/9 phosphorylation and increasing the expression levels of Runx2 and Osterix. NIR light treatment may act through sodium voltage-gated channel Scn4a, which may be a potential responder of NIR light to accelerate bone regeneration. Together, these findings suggest that low-intensity NIR light may promote in situ bone regeneration in a CRY1-dependent manner, providing a novel, efficient and non-invasive strategy to promote bone regeneration for clinical bone defects.


Assuntos
Regeneração Óssea , Relógios Circadianos , Criptocromos , Animais , Ratos , Proteína Morfogenética Óssea 2/metabolismo , Diferenciação Celular , Criptocromos/metabolismo , Osteoblastos/metabolismo , Osteogênese , Fatores de Transcrição/metabolismo
14.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 36(11): 1428-1433, 2022 Nov 15.
Artigo em Chinês | MEDLINE | ID: mdl-36382463

RESUMO

Objective: To summarize the characteristics of the occurrence and development of osteonecrosis of the femoral head (ONFH), and to review the important regulatory role of immune cells in the progression of ONFH. Methods: The domestic and foreign literature on the immune regulation of ONFH was reviewed, and the relationship between immune cells and the occurrence and development of ONFH was analyzed. Results: The ONFH region has a chronic inflammatory reaction and an imbalance between osteoblast and osteoclast, while innate immune cells such as macrophages, neutrophils, dendritic cells, and immune effector cells such as T cells and B cells are closely related to the maintenance of bone homeostasis. Conclusion: Immunotherapy targeting the immune cells in the ONFH region and the key factors and proteins in their regulatory pathways may be a feasible method to delay the occurrence, development, and even reverse the pathology of ONFH.


Assuntos
Necrose da Cabeça do Fêmur , Células-Tronco Mesenquimais , Osteonecrose , Humanos , Cabeça do Fêmur/patologia , Necrose da Cabeça do Fêmur/etiologia , Necrose da Cabeça do Fêmur/patologia , Células-Tronco Mesenquimais/metabolismo , Osteoblastos/metabolismo , Osteoclastos/metabolismo
15.
Int J Mol Sci ; 23(21)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36362346

RESUMO

Suffruticosol B (Suf-B) is a stilbene found in Paeonia suffruticosa ANDR., which has been traditionally used in medicine. Stilbenes and their derivatives possess various pharmacological effects, such as anticancer, anti-inflammatory, and anti-osteoporotic activities. This study aimed to explore the bone-forming activities and mechanisms of Suf-B in pre-osteoblasts. Herein, >99.9% pure Suf-B was isolated from P. suffruticosa methanolic extracts. High concentrations of Suf-B were cytotoxic, whereas low concentrations did not affect cytotoxicity in pre-osteoblasts. Under zero levels of cytotoxicity, Suf-B exhibited bone-forming abilities by enhancing alkaline phosphatase enzyme activities, bone matrix calcification, and expression levels with non-collagenous proteins. Suf-B induces intracellular signal transduction, leading to nuclear RUNX2 expression. Suf-B-stimulated differentiation showed increases in autophagy proteins and autophagosomes, as well as enhancement of osteoblast adhesion and transmigration on the ECM. These results indicate that Suf-B has osteogenic qualities related to differentiation, autophagy, adhesion, and migration. This also suggests that Suf-B could have a therapeutic effect as a phytomedicine in skeletal disorders.


Assuntos
Paeonia , Estilbenos , Osteogênese , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Osteoblastos/metabolismo , Autofagia , Paeonia/metabolismo , Estilbenos/farmacologia , Diferenciação Celular
16.
Dis Markers ; 2022: 9872243, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36340581

RESUMO

Purpose: Osteoporosis is a complication of type 2 diabetes, and it is characterized by reduced bone mass, augmented bone fragility, and increased risk of fracture, thus reducing patient quality of life, especially in the elderly. Ferroptosis has been implicated in the pathological process of type 2 diabetic osteoporosis (T2DOP), but the specific underlying mechanisms remain largely unknown. This study clarified the role of activating transcription factor 3 (ATF3) in T2DOP and explored its specific regulatory mechanism, providing a new treatment target for T2DOP. Methods: We cultured hFob1.19 cells in high glucose (HG, 35 mM) and knocked down ATF3 using short hairpin RNA (shRNA). We then measured cell viability, assessed morphology, quantified the expression of ATF3 and glutathione peroxidase 4 (GPX4), detected the levels of reactive oxygen species (ROS) and lipid peroxides, and determined the osteogenic function of osteoblasts. Cystine/glutamate antiporter (system Xc-) activity was evaluated by determining the expression of SLC7A11 and the levels of glutathione (GSH) and extracellular glutamate. We constructed a T2DOP rat model and observed the effect of ATF3 on ferroptosis and T2DOP by knocking down ATF3 using small interfering RNA (siRNA). Then, we evaluated the levels of iron metabolism, lipid peroxidation, and bone turnover in serum, detected the expression of ATF3, SLC7A11, and GPX4 in bone tissues, and assessed bone microstructure using microcomputed tomography. Results: ATF3 expression was increased in osteoblasts under HG condition and in T2DOP rats. Inhibiting the function of ATF3 increased GPX4 levels and reduced the accumulation of ROS and lipid peroxides. These changes inhibited the ferroptosis of osteoblasts and improved osteogenic function. In addition, HG induced ATF3 upregulation, resulting in decreased SLC7A11 expression and lower levels of intracellular GSH and extracellular glutamate. Conclusion: Osteoblast ferroptosis under HG conditions is induced by ATF3-mediated inhibition of system Xc- activity, and these events contribute to T2DOP pathogenesis.


Assuntos
Diabetes Mellitus Tipo 2 , Ferroptose , Osteoporose , Ratos , Animais , Fator 3 Ativador da Transcrição/genética , Fator 3 Ativador da Transcrição/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Peróxidos Lipídicos , Diabetes Mellitus Tipo 2/complicações , Microtomografia por Raio-X , Qualidade de Vida , Osteoblastos/metabolismo , Osteoporose/genética , Glutamatos
17.
Biomater Adv ; 142: 213170, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36341745

RESUMO

Cellular microenvironments play a crucial role in cell behavior. In addition to the biochemical cues present in the microenvironments, biophysical and biomechanical properties on surfaces have an impact on cellular functionality and eventually cellular fate. Effects of surface topography on cell behavior are being studied extensively in the literature. However, these studies often try to replicate topographical features of tissue surfaces by using techniques such as chemical etching, photolithography, and electrospinning, which may result in the loss of crucial micro- and nano- features on the tissue surfaces such as bone. This study investigates the topographical effects of bone surface by transferring its surface features onto polydimethylsiloxane (PDMS) membranes using soft lithography from a bovine femur. Our results have shown that major features on bone surfaces were successfully transferred onto PDMS using soft lithography. Osteoblast proliferation and calcification of bone matrix have significantly increased along with osteoblast-specific differentiation and maturation markers such as osteocalcin (OSC), osterix (OSX), collagen type I alpha 1 chain (COL1A1), and alkaline phosphatase (ALP) on bone surface mimicked (BSM) PDMS membranes in addition to a unidirectional alignment of osteoblast cells compared to plain PDMS surfaces. This presented bone surface mimicking method can provide a versatile native-like platform for further investigation of intracellular pathways regarding osteoblast growth and differentiation.


Assuntos
Matriz Óssea , Osteoblastos , Animais , Bovinos , Propriedades de Superfície , Calcificação Fisiológica , Dimetilpolisiloxanos/farmacologia
18.
Drug Des Devel Ther ; 16: 3929-3946, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36411860

RESUMO

Purpose: Long-term glucocorticoid- usage can lead to glucocorticoid-induced osteoporosis (GIOP). The study focused on the preventative effects of a novel active vitamin D3 analog, eldecalcitol (ED-71), against GIOP and explored the underlying molecular mechanisms. Methods: Intraperitoneal injection of methylprednisolone (MPED) or dexamethasone (DEX) induced the GIOP model within C57BL/6 mice in vivo. Simultaneously, ED-71 was orally supplemented. Bone histological alterations, microstructure parameters, novel bone formation rates, and osteogenic factor changes were evaluated by hematoxylin-eosin (HE) staining, micro-computed tomography, calcein/tetracycline labeling, and immunohistochemical (IHC) staining. The osteogenic differentiation level and mineralization in pre-osteoblast MC3T3-E1 cells were evaluated in vitro using alkaline phosphatase (ALP) staining, alizarin red (AR) staining, quantitative polymerase chain reaction (qPCR), Western blotting, and immunofluorescence staining. Results: ED-71 partially prevented bone mass reduction and microstructure parameter alterations among GIOP-induced mice. Moreover, ED-71 also promoted new bone formation and osteoblast activity while inhibiting osteoclasts. In vitro, ED-71 promoted osteogenic differentiation and mineralization in DEX-treated MC3T3-E1 cells and boosted the levels of osteogenic-related factors. Additionally, GSK3-ß and ß-catenin expression levels were elevated after ED-71 was added to cells and were accompanied by reduced Notch expression. The Wnt signaling inhibitor XAV939 and Notch overexpression reversed the ED-71 promotional effects toward osteogenic differentiation and mineralization. Conclusion: ED-71 prevented GIOP by enhancing osteogenic differentiation through Notch and Wnt/GSK-3ß/ß-catenin signaling. The results provide a novel translational direction for the clinical application of ED-71 against GIOP.


Assuntos
Osteogênese , Osteoporose , Camundongos , Animais , beta Catenina/metabolismo , Via de Sinalização Wnt , Glucocorticoides/uso terapêutico , Glicogênio Sintase Quinase 3 beta/metabolismo , Microtomografia por Raio-X , Quinase 3 da Glicogênio Sintase/metabolismo , Quinase 3 da Glicogênio Sintase/farmacologia , Quinase 3 da Glicogênio Sintase/uso terapêutico , Camundongos Endogâmicos C57BL , Osteoporose/induzido quimicamente , Osteoporose/tratamento farmacológico , Osteoporose/prevenção & controle , Osteoblastos
19.
Sci Adv ; 8(46): eadc9222, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36383652

RESUMO

Cell fate determination of human mesenchymal stem/stromal cells (hMSCs) is precisely regulated by lineage-specific transcription factors and epigenetic enzymes. We found that CTR9, a key scaffold subunit of polymerase-associated factor complex (PAFc), selectively regulates hMSC differentiation to osteoblasts and chondrocytes, but not to adipocytes. An in vivo ectopic osteogenesis assay confirmed the essentiality of CTR9 in hMSC-derived bone formation. CTR9 counteracts the activity of Enhancer Of Zeste 2 (EZH2), the epigenetic enzyme that deposits H3K27me3, in hMSCs. Accordingly, CTR9 knockdown (KD) hMSCs gain H3K27me3 mark, and the osteogenic differentiation defects of CTR9 KD hMSCs can be partially rescued by treatment with EZH2 inhibitors. Transcriptome analyses identified bone morphology protein-2 (BMP-2) as a downstream effector of CTR9. BMP-2 secretion, membrane anchorage, and the BMP-SMAD pathway were impaired in CTR9 KD MSCs, and the effects were rescued by BMP-2 supplementation. This study uncovers an epigenetic mechanism engaging the CTR9-H3K27me3-BMP-2 axis to regulate the osteochondral lineage differentiation of hMSCs.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Humanos , Células-Tronco Mesenquimais/metabolismo , Epigênese Genética , Histonas/metabolismo , Diferenciação Celular/genética , Osteoblastos , Fosfoproteínas/metabolismo , Fatores de Transcrição/metabolismo
20.
Elife ; 112022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36326085

RESUMO

The spatiotemporal blood vessel formation and specification at the osteogenic and angiogenic interface of murine cranial bone defect repair were examined utilizing a high-resolution multiphoton-based imaging platform in conjunction with advanced optical techniques that allow interrogation of the oxygen microenvironment and cellular energy metabolism in living animals. Our study demonstrates the dynamic changes of vessel types, that is, arterial, venous, and capillary vessel networks at the superior and dura periosteum of cranial bone defect, suggesting a differential coupling of the vessel type with osteoblast expansion and bone tissue deposition/remodeling during repair. Employing transgenic reporter mouse models that label distinct types of vessels at the site of repair, we further show that oxygen distributions in capillary vessels at the healing site are heterogeneous as well as time- and location-dependent. The endothelial cells coupling to osteoblasts prefer glycolysis and are less sensitive to microenvironmental oxygen changes than osteoblasts. In comparison, osteoblasts utilize relatively more OxPhos and potentially consume more oxygen at the site of repair. Taken together, our study highlights the dynamics and functional significance of blood vessel types at the site of defect repair, opening up opportunities for further delineating the oxygen and metabolic microenvironment at the interface of bone tissue regeneration.


Assuntos
Células Endoteliais , Microscopia , Camundongos , Animais , Osteogênese , Crânio/diagnóstico por imagem , Osteoblastos/metabolismo , Camundongos Transgênicos , Oxigênio/metabolismo , Diferenciação Celular
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