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Journal of Nanobiotechnology Jun 2024Recently, environmental temperature has been shown to regulate bone homeostasis. However, the mechanisms by which cold exposure affects bone mass remain unclear. In our...
Recently, environmental temperature has been shown to regulate bone homeostasis. However, the mechanisms by which cold exposure affects bone mass remain unclear. In our present study, we observed that exposure to cold temperature (CT) decreased bone mass and quality in mice. Furthermore, a transplant of exosomes derived from the plasma of mice exposed to cold temperature (CT-EXO) can also impair the osteogenic differentiation of BMSCs and decrease bone mass by inhibiting autophagic activity. Rapamycin, a potent inducer of autophagy, can reverse cold exposure or CT-EXO-induced bone loss. Microarray sequencing revealed that cold exposure increases the miR-25-3p level in CT-EXO. Mechanistic studies showed that miR-25-3p can inhibit the osteogenic differentiation and autophagic activity of BMSCs. It is shown that inhibition of exosomes release or downregulation of miR-25-3p level can suppress CT-induced bone loss. This study identifies that CT-EXO mediates CT-induced osteoporotic effects through miR-25-3p by inhibiting autophagy via targeting SATB2, presenting a novel mechanism underlying the effect of cold temperature on bone mass.
Topics: Animals; Autophagy; Mice; Exosomes; MicroRNAs; Cold Temperature; Osteogenesis; Mice, Inbred C57BL; Mesenchymal Stem Cells; Osteoporosis; Cell Differentiation; Bone and Bones; Female; Bone Density; Sirolimus
PubMed: 38910236
DOI: 10.1186/s12951-024-02640-z -
Journal of Ovarian Research Jun 2024Teratomas are a common type of germ cell tumor. However, only a few reports on their genomic constitution have been published. The study of teratomas may provide a...
Amplifications of EVX2 and HOXD9-HOXD13 on 2q31 in mature cystic teratomas of the ovary identified by array comparative genomic hybridization may explain teratoma characteristics in chondrogenesis and osteogenesis.
BACKGROUND
Teratomas are a common type of germ cell tumor. However, only a few reports on their genomic constitution have been published. The study of teratomas may provide a better understanding of their stepwise differentiation processes and molecular bases, which could prove useful for the development of tissue-engineering technologies.
METHODS
In the present study, we analyzed the copy number aberrations of nine ovarian mature cystic teratomas using array comparative genomic hybridization in an attempt to reveal their genomic aberrations.
RESULTS
The many chromosomal aberrations observed on array comparative genomic hybridization analysis reveal the complex genetics of this tumor. Amplifications and deletions of large DNA fragments were observed in some samples, while amplifications of EVX2 and HOXD9-HOXD13 on 2q31.1, NDUFV1 on 11q13.2, and RPL10, SNORA70, DNASE1L1, TAZ, ATP6AP1, and GDI1 on Xq28 were found in all nine mature cystic teratomas.
CONCLUSIONS
Our results indicated that amplifications of these genes may play an important etiological role in teratoma formation. Moreover, amplifications of EVX2 and HOXD9-HOXD13 on 2q31.1, found on array comparative genomic hybridization, may help to explain the characteristics of teratomas in chondrogenesis and osteogenesis.
Topics: Humans; Female; Teratoma; Comparative Genomic Hybridization; Ovarian Neoplasms; Transcription Factors; Homeodomain Proteins; Osteogenesis; Chondrogenesis; Adult; Middle Aged; Neoplasm Proteins
PubMed: 38907278
DOI: 10.1186/s13048-024-01458-5 -
Journal of Orthopaedic Surgery and... Jun 2024Long non-coding RNAs (LncRNAs) are recognized as a pivotal element in the processes of fracture healing and the osteogenic differentiation of stem cells. This study...
BACKGROUND
Long non-coding RNAs (LncRNAs) are recognized as a pivotal element in the processes of fracture healing and the osteogenic differentiation of stem cells. This study investigated the molecular mechanism and regulatory significance of lncRNA MAGI2-AS3 (MAGI2-AS3) in fracture healing.
METHODS
Serum levels of MAGI2-AS3 in patients with normal and delayed fracture healing were verified by RT-qPCR assays. The predictive efficacy of MAGI2-AS3 for delayed fracture healing was analyzed by ROC curve. Osteogenic markers were quantified by RT-qPCR assays. MC3T3-E1 cell viability was detected using CCK-8 assay, and flow cytometry was utilized to measure cell apoptosis. The dual-luciferase reporter gene assay was used to determine the targeted binding between MAGI2-AS3 and miR-223-3p.
RESULTS
Serum MAGI2-AS3 expression was decreased in patients with delayed fracture healing compared with patients with normal healing. Elevated MAGI2-AS3 resulted in an upregulation of the proliferative capacity of MC3T3-E1 cells and a decrease in mortality, along with increased levels of both osteogenic markers. However, after transfection silencing MAGI2-AS3, the trend was reversed. Additionally, miR-223-3p was the downstream target of MAGI2-AS3 and was controlled by MAGI2-AS3. miR-223-3p mimic reversed the promoting effects of MAGI2-AS3 overexpression on osteogenic marker levels and cell growth, and induced cell apoptosis.
CONCLUSION
The upregulation of MAGI2-AS3 may expedite the healing of fracture patients by targeting miR-223-3p, offering a novel biomarker for diagnosing patients with delayed healing.
Topics: MicroRNAs; RNA, Long Noncoding; Fracture Healing; Humans; Down-Regulation; Mice; Animals; Osteogenesis; Male; Female; Apoptosis; Adaptor Proteins, Signal Transducing; Adult; Cell Proliferation; Cell Differentiation
PubMed: 38907263
DOI: 10.1186/s13018-024-04850-5 -
Frontiers in Endocrinology 2024Caloric restriction (CR) is a nutritional intervention that increases life expectancy while lowering the risk for cardio-metabolic disease. Its effects on bone health,...
INTRODUCTION
Caloric restriction (CR) is a nutritional intervention that increases life expectancy while lowering the risk for cardio-metabolic disease. Its effects on bone health, however, remain controversial. For instance, CR has been linked to increased accumulation of bone marrow adipose tissue (BMAT) in long bones, a process thought to elicit detrimental effects on bone. Qualitative differences have been reported in BMAT in relation to its specific anatomical localization, subdividing it into physiological and potentially pathological BMAT. We here examine the local impact of CR on bone composition, microstructure and its endocrine profile in the context of aging.
METHODS
Young and aged male C57Bl6J mice were subjected to CR for 8 weeks and were compared to age-matched littermates with free food access. We assessed bone microstructure and BMAT by micro-CT, bone fatty acid and transcriptomic profiles, and bone healing.
RESULTS
CR increased tibial BMAT accumulation and adipogenic gene expression. CR also resulted in elevated fatty acid desaturation in the proximal and mid-shaft regions of the tibia, thus more closely resembling the biochemical lipid profile of the distally located, physiological BMAT. In aged mice, CR attenuated trabecular bone loss, suggesting that CR may revert some aspects of age-related bone dysfunction. Cortical bone, however, was decreased in young mice on CR and remained reduced in aged mice, irrespective of dietary intervention. No negative effects of CR on bone regeneration were evident in either young or aged mice.
DISCUSSION
Our findings indicate that the timing of CR is critical and may exert detrimental effects on bone biology if administered during a phase of active skeletal growth. Conversely, CR exerts positive effects on trabecular bone structure in the context of aging, which occurs despite substantial accumulation of BMAT. These data suggest that the endocrine profile of BMAT, rather than its fatty acid composition, contributes to healthy bone maintenance in aged mice.
Topics: Animals; Male; Caloric Restriction; Mice; Aging; Mice, Inbred C57BL; Cancellous Bone; Adipocytes; Bone Marrow; Tibia
PubMed: 38904042
DOI: 10.3389/fendo.2024.1394263 -
International Journal of Medical... 2024Bone marrow-derived mesenchymal stem cells (MSCs), which are capable of differentiating into osteoblasts, are used in effective regenerative therapies. MSCs must be...
Bone marrow-derived mesenchymal stem cells (MSCs), which are capable of differentiating into osteoblasts, are used in effective regenerative therapies. MSCs must be prompted to differentiate into osteoblasts for MSC transplantation to be effective. In this study, osteoblast differentiation markers involved in bone formation were evaluated to investigate the stress resistance of bone marrow-derived rat MSCs to dexamethasone and hypoxia and their ability to differentiate into osteoblasts. MSCs were allowed to differentiate into osteoblasts for 21 days in three different environments (dexamethasone treatment, hypoxic conditions [1% oxygen], or both). Osteoblast differentiation potential was evaluated according to alkaline phosphatase levels and a mineralisation assay. Immunofluorescence staining was used to determine the protein expression of the osteoblast differentiation markers type I collagen and osteopontin. MSCs differentiated into osteoblasts under hypoxic conditions but differentiated more slowly upon treatment with dexamethasone and dexamethasone plus hypoxia relative to the control. MSCs preconditioned with dexamethasone or hypoxia and then allowed to differentiate into osteoblasts under similar conditions differentiated comparably to control MSCs. MSCs that developed resistance to dexamethasone or hypoxia differentiated more quickly into osteoblasts than those that did not. The findings suggest that increasing the resistance of MSCs to stress by preconditioning them via dexamethasone or hypoxia exposure could result in more rapid differentiation into osteoblasts following transplantation.
Topics: Dexamethasone; Mesenchymal Stem Cells; Animals; Osteoblasts; Cell Differentiation; Rats; Cell Hypoxia; Osteogenesis; Cells, Cultured; Alkaline Phosphatase; Humans; Mesenchymal Stem Cell Transplantation; Collagen Type I; Male
PubMed: 38903930
DOI: 10.7150/ijms.91222 -
Regenerative Biomaterials 2024Lately, the potential risk of disease transmission due to the use of bovine-derived bone substitutes has become obvious, demonstrating the urgent need for a synthetic...
Effect of a synthetic hydroxyapatite-based bone grafting material compared to established bone substitute materials on regeneration of critical-size bone defects in the ovine scapula.
Lately, the potential risk of disease transmission due to the use of bovine-derived bone substitutes has become obvious, demonstrating the urgent need for a synthetic grafting material with comparable bioactive behaviour and properties. Therefore, the effect of a synthetic hydroxyapatite (HA) (Osbone) bone grafting material on bone regeneration was evaluated 2 weeks, 1 month, and 3, 6, 12 and 18 months after implantation in critical-size bone defects in the ovine scapula and compared to that of a bovine-derived HA (Bio-Oss) and β-tricalcium phosphate (TCP) (Cerasorb M). New bone formation and the biodegradability of the bone substitutes were assessed histomorphometrically. Hard tissue histology and immunohistochemical analysis were employed to characterize collagen type I, alkaline phosphatase, osteocalcin, as well as bone sialoprotein expression in the various cell and matrix components of the bone tissue to evaluate the bioactive properties of the bone grafting materials. No inflammatory tissue response was detected with any of the bone substitute materials studied. After 3 and 6 months, β-TCP (Cerasorb M) showed superior bone formation when compared to both HA-based materials (3 months: β-TCP 55.65 ± 2.03% vs. SHA 49.05 ± 3.84% and BHA 47.59 ± 1.97%; ≤0.03; 6 months: β-TCP 62.03 ± 1.58%; SHA: 55.83 ± 2.59%; BHA: 53.44 ± 0.78%; ≤0.04). Further, after 12 and 18 months, a similar degree of bone formation and bone-particle contact was noted for all three bone substitute materials without any significant differences. The synthetic HA supported new bone formation, osteogenic marker expression, matrix mineralization and good bone-bonding behaviour to an equal and even slightly superior degree compared to the bovine-derived HA. As a result, synthetic HA can be regarded as a valuable alternative to the bovine-derived HA without the potential risk of disease transmission.
PubMed: 38903563
DOI: 10.1093/rb/rbae041 -
Distractor position and distraction amplitude in fronto-facial monobloc advancement : A case series.Journal of Stomatology, Oral and... Jun 2024Fronto-facial monobloc advancement with internal distraction (FFMBA) is a central procedure in the management of faciocraniosynostoses. In techniques with internal...
Fronto-facial monobloc advancement with internal distraction (FFMBA) is a central procedure in the management of faciocraniosynostoses. In techniques with internal distraction, two sets of devices are generally positioned: bilateral fronto-orbital and temporo-zygomatic distractors, using a temporal tongue and groove osteotomy design. It is believed that distractors must be positioned as parallel as possible in the horizontal and sagittal planes to avoid mechanical conflicts between the sliding bone fragments of the tongue and groove during distraction, and thus optimize the advancement amplitude. Several approaches involving surgical planification and guides for distractor positioning have thus been proposed to monitor distractor placement. To explore the need for surgical planification in distractor placement, the parallelism of the position of the 4 distractors was assessed in 19 FFMBA procedures and we correlated a set of 10 distractor angles with the degree of advancement. We report that the horizontal cut of the tongue and groove can be used as a landmark for the positioning of the lower, temporo-zygomatic, distractor in fronto-facial monobloc advancement. Other parameters (relative position of the two homolateral and the two contralateral distractors and the orientations of the vertical and horizontal cuts of the tongue and groove) do not interfere with distraction, other things being equal. Our results indicate that distractor orientation is not a critical issue in fronto-facial monobloc advancement when devices are positioned as parallel as possible based on visual monitoring.
PubMed: 38897383
DOI: 10.1016/j.jormas.2024.101942 -
Environmental Health Perspectives Jun 2024Cadmium (Cd) is a highly toxic and widespread environmental oxidative stressor that causes a myriad of health problems, including osteoporosis and bone damage. Although...
BACKGROUND
Cadmium (Cd) is a highly toxic and widespread environmental oxidative stressor that causes a myriad of health problems, including osteoporosis and bone damage. Although nuclear factor erythroid 2-related factor 2 (NRF2) and its Cap 'n' Collar and basic region Leucine Zipper (CNC-bZIP) family member nuclear factor erythroid 2-related factor 1 (NRF1) coordinate various stress responses by regulating the transcription of a variety of antioxidant and cytoprotective genes, they play distinct roles in bone metabolism and remodeling. However, the precise roles of both transcription factors in bone loss induced by prolonged Cd exposure remain unclear.
OBJECTIVES
We aimed to understand the molecular mechanisms underlying Cd-induced bone loss, focusing mainly on the roles of NRF2 and NRF1 in osteoclastogenesis provoked by Cd.
METHODS
Male wild-type (WT), global -knockout () and myeloid-specific knockout [(M)-KO] mice were administered Cd (50 or ) via drinking water for 8 or 16 wk, followed by micro-computed tomography, histological analyses, and plasma biochemical testing. Osteoclastogenesis was evaluated using bone marrow-derived osteoclast progenitor cells (BM-OPCs) and RAW 264.7 cells in the presence of Cd (10 or ) with a combination of genetic and chemical modulations targeting NRF2 and NRF1.
RESULTS
Compared with relevant control mice, global or (M)-KO mice showed exacerbated bone loss and augmented osteoclast activity following exposure to Cd in drinking water for up to 16 wk. osteoclastogenic analyses suggested that -deficient BM-OPCs and RAW 264.7 cells responded more robustly to low levels of Cd (up to ) with regard to osteoclast differentiation compared with WT cells. Further mechanistic studies supported a compensatory up-regulation of long isoform of NRF1 (L-NRF1) and subsequent induction of nuclear factor of activated T cells, cytoplasmic, calcineurin dependent 1 (NFATc1) as the key molecular events in the deficiency-worsened and Cd-provoked osteoclastogenesis. L- silenced (via lentiviral means) -knockdown (KD) RAW cells exposed to Cd showed dramatically different NFATc1 and subsequent osteoclastogenesis outcomes compared with the cells of -KD alone exposed to Cd, suggesting a mitigating effect of the silencing. In addition, suppression of reactive oxygen species by exogenous antioxidants -acetyl-l-cysteine () and mitoquinone mesylate (MitoQ; ) mitigated the L-NRF1-associated effects on NFATc1-driven osteoclastogenesis outcomes in Cd-exposed -KD cells.
CONCLUSIONS
This and study supported the authors' hypothesis that Cd exposure caused bone loss, in which NRF2 and L-NRF1 responded to Cd and osteoclastogenic stimuli in a cooperative, but contradictive, manner to coordinate expression, osteoclastogenesis and thus bone homeostasis. Our study suggests a novel strategy targeting NRF2 and L-NRF1 to prevent and treat the bone toxicity of Cd. https://doi.org/10.1289/EHP13849.
Topics: Animals; Mice; Male; Cadmium; NF-E2-Related Factor 2; Osteoclasts; Osteogenesis; Mice, Knockout; NF-E2-Related Factor 1; Mice, Inbred C57BL; Cell Differentiation
PubMed: 38896780
DOI: 10.1289/EHP13849 -
Cancers May 2024Myeloid and lymphoid neoplasms share the characteristics of potential bone marrow infiltration as a primary or secondary effect, which readily leads to hematopoietic...
Myeloid and lymphoid neoplasms share the characteristics of potential bone marrow infiltration as a primary or secondary effect, which readily leads to hematopoietic insufficiency. The mechanisms by which clonal malignant cells inhibit normal hematopoietic stem and progenitor cells (HSPCs) in the bone marrow (BM) have not been unraveled so far. Given the pivotal role of mesenchymal stromal cells (MSCs) in the regulation of hematopoiesis in the BM niche it is assumed that MSCs also play a relevant role in the pathogenesis of hematological neoplasms. We aimed to identify overlapping mechanisms in MSCs derived from myeloid and lymphoid neoplasms contributing to disease progression and suppression of HSPCs to develop interventions that target these mechanisms. MSCs derived from healthy donors ( = 44) and patients diagnosed with myeloproliferative neoplasia ( = 11), myelodysplastic syndromes ( = 16), or acute myeloid leukemia ( = 25) and B-Non-Hodgkin lymphoma ( = 9) with BM infiltration and acute lymphoblastic leukemia ( = 9) were analyzed for their functionality and by RNA sequencing. A reduced growth and differentiation capacity of MSCs was found in all entities. RNA sequencing distinguished both groups but clearly showed overlapping differentially expressed genes, including major players in the BMP/TGF and WNT-signaling pathway which are crucial for growth, osteogenesis, and hematopoiesis. Functional alterations in healthy MSCs were inducible by exposure to supernatants from malignant cells, implicating the involvement of these factors in disease progression. Overall, we were able to identify overlapping factors that pose potential future therapeutic targets.
PubMed: 38893194
DOI: 10.3390/cancers16112071 -
International Journal of Molecular... May 2024In exploring the challenges of bone repair and regeneration, this review evaluates the potential of bone tissue engineering (BTE) as a viable alternative to traditional... (Review)
Review
In exploring the challenges of bone repair and regeneration, this review evaluates the potential of bone tissue engineering (BTE) as a viable alternative to traditional methods, such as autografts and allografts. Key developments in biomaterials and scaffold fabrication techniques, such as additive manufacturing and cell and bioactive molecule-laden scaffolds, are discussed, along with the integration of bio-responsive scaffolds, which can respond to physical and chemical stimuli. These advancements collectively aim to mimic the natural microenvironment of bone, thereby enhancing osteogenesis and facilitating the formation of new tissue. Through a comprehensive combination of in vitro and in vivo studies, we scrutinize the biocompatibility, osteoinductivity, and osteoconductivity of these engineered scaffolds, as well as their interactions with critical cellular players in bone healing processes. Findings from scaffold fabrication techniques and bio-responsive scaffolds indicate that incorporating nanostructured materials and bioactive compounds is particularly effective in promoting the recruitment and differentiation of osteoprogenitor cells. The therapeutic potential of these advanced biomaterials in clinical settings is widely recognized and the paper advocates continued research into multi-responsive scaffold systems.
Topics: Tissue Engineering; Tissue Scaffolds; Humans; Bone Regeneration; Animals; Bone and Bones; Biocompatible Materials; Osteogenesis; Cell Differentiation
PubMed: 38892199
DOI: 10.3390/ijms25116012