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1.
FASEB J ; 38(10): e23646, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38795328

RESUMO

Multiple regulatory mechanisms are in place to ensure the normal processes of bone metabolism, encompassing both bone formation and absorption. This study has identified chaperone-mediated autophagy (CMA) as a critical regulator that safeguards bone formation from the detrimental effects of excessive inflammation. By silencing LAMP2A or HSCA8, we observed a hindrance in the osteoblast differentiation of human bone marrow mesenchymal stem cells (hBMSCs) in vitro. To further elucidate the role of LAMP2A, we generated LAMP2A gene knockdown and overexpression of mouse BMSCs (mBMSCs) using adenovirus. Our results showed that LAMP2A knockdown led to a decrease in osteogenic-specific proteins, while LAMP2A overexpression favored the osteogenesis of mBMSCs. Notably, active-ß-catenin levels were upregulated by LAMP2A overexpression. Furthermore, we found that LAMP2A overexpression effectively protected the osteogenesis of mBMSCs from TNF-α, through the PI3K/AKT/GSK3ß/ß-catenin pathway. Additionally, LAMP2A overexpression significantly inhibited osteoclast hyperactivity induced by TNF-α. Finally, in a murine bone defect model, we demonstrated that controlled release of LAMP2A overexpression adenovirus by alginate sodium capsule efficiently protected bone healing from inflammation, as confirmed by imaging and histological analyses. Collectively, our findings suggest that enhancing CMA has the potential to safeguard bone formation while mitigating hyperactivity in bone absorption.


Assuntos
Autofagia Mediada por Chaperonas , Glicogênio Sintase Quinase 3 beta , Inflamação , Proteína 2 de Membrana Associada ao Lisossomo , Células-Tronco Mesenquimais , Osteogênese , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , beta Catenina , Animais , Osteogênese/fisiologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Glicogênio Sintase Quinase 3 beta/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , beta Catenina/metabolismo , Humanos , Células-Tronco Mesenquimais/metabolismo , Inflamação/metabolismo , Proteína 2 de Membrana Associada ao Lisossomo/metabolismo , Proteína 2 de Membrana Associada ao Lisossomo/genética , Transdução de Sinais , Masculino , Camundongos Endogâmicos C57BL , Osteoblastos/metabolismo , Diferenciação Celular , Osteoclastos/metabolismo
2.
FASEB J ; 37(6): e22950, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37144883

RESUMO

Fracture nonunion and bone defects are challenging for orthopedic surgeons. Milk fat globule-epidermal growth factor 8 (MFG-E8), a glycoprotein possibly secreted by macrophages in a fracture hematoma, participates in bone development. However, the role of MFG-E8 in the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) is unclear. We investigated the osteogenic effect of MFG-E8 in vitro and in vivo. The CCK-8 assay was used to assess the effect of recombinant human MFG-E8 (rhMFG-E8) on the viability of hBMSCs. Osteogenesis was investigated using RT-PCR, Western blotting, and immunofluorescence. Alkaline phosphatase (ALP) and Alizarin red staining were used to evaluate ALP activity and mineralization, respectively. An enzyme-linked immunosorbent assay was conducted to evaluate the secretory MFG-E8 concentration. Knockdown and overexpression of MFG-E8 in hBMSCs were established via siRNA and lentivirus vector transfection, respectively. Exogenous rhMFG-E8 was used to verify the in vivo therapeutic effect in a tibia bone defect model based on radiographic analysis and histological evaluation. Endogenous and secretory MFG-E8 levels increased significantly during the early osteogenic differentiation of hBMSCs. Knockdown of MFG-E8 inhibited the osteogenic differentiation of hBMSCs. Overexpression of MFG-E8 and rhMFG-E8 protein increased the expression of osteogenesis-related genes and proteins and enhanced calcium deposition. The active ß-catenin to total ß-catenin ratio and the p-GSK3ß protein level were increased by MFG-E8. The MFG-E8-induced enhanced osteogenic differentiation of hBMSCs was partially attenuated by a GSK3ß/ß-catenin signaling inhibitor. Recombinant MFG-E8 accelerated bone healing in a rat tibial-defect model. In conclusion, MFG-E8 promotes the osteogenic differentiation of hBMSCs by regulating the GSK3ß/ß-catenin signaling pathway and so, is a potential therapeutic target.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Humanos , Ratos , Animais , Osteogênese/fisiologia , beta Catenina/genética , beta Catenina/metabolismo , Fator VIII/metabolismo , Fator VIII/farmacologia , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Transdução de Sinais/fisiologia , Diferenciação Celular/fisiologia , Glicoproteínas/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células Cultivadas , Via de Sinalização Wnt , Células da Medula Óssea/metabolismo
3.
Langmuir ; 39(13): 4847-4854, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-36944145

RESUMO

Mixed brushes consisting of flexible and semiflexible polymers of the same chain length exhibit a height-switching phenomenon because of rigidity-dependent critical adsorption [Yang et al. Macromolecules 2020, 53, 7369]. Semiflexible polymers stand higher at weak surface attraction (high temperature), but they close to the attractive surface at strong attraction (low temperature). In this work, the height-switching dynamics of the mixed polymer brushes is studied by Metropolis Monte Carlo simulation. The height-switching time is calculated by a sudden change in the surface attraction. Two surface attraction change modes, i.e., the weak-to-strong mode where the attraction is changed from weak to strong and the strong-to-weak mode where it is changed from strong to weak, are investigated. Simulation results show that the height-switching time is related to the grafting density, the polymer stiffness, and surface attraction change mode. We find that the height-switching time is significantly decreased for the strong-to-weak mode. And our results also show that the height switching in the mixed polymer brushes is reversible.

4.
FASEB J ; 34(4): 5483-5498, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32107793

RESUMO

Low back pain (LBP) is one of the most common complains in orthopedic outpatient department and intervertebral disc degeneration (IDD) is one of the most important reasons of LBP. The mechanisms of IDD contain a complex biochemical cascade which includes inflammation, vascular ingrowth, and results in degradation of matrix. In our study, we used both in vitro and in vivo models to investigate the relation between tissue inhibitor of metalloproteinase-3 (TIMP3) expression and IDD. Loss of TIMP3 expression was found in degenerative intervertebral disc (IVD), this change of expression was closely related with the dephosphorylation of smad2/3. Overexpression of TIMP3 significantly inhibited the release of TNF-α and matrix degradation induced by Lipopolysaccharide. Vascular ingrowth was also suppressed by TIMP3 in the in vitro and in vivo models. Further, animal experiments confirmed that the degeneration of IVD was reduced after overexpression of TIMP3 in nucleus pulposus. Taken together, our results indicated TIMP-3 might play an important role in the pathogenesis of IDD and therefore be a potential therapeutic target in the future.


Assuntos
Matriz Extracelular/patologia , Inflamação/patologia , Degeneração do Disco Intervertebral/patologia , Neovascularização Patológica/patologia , Núcleo Pulposo/patologia , Inibidor Tecidual de Metaloproteinase-3/deficiência , Adulto , Idoso , Animais , Células Cultivadas , Matriz Extracelular/metabolismo , Feminino , Humanos , Inflamação/genética , Inflamação/metabolismo , Degeneração do Disco Intervertebral/genética , Degeneração do Disco Intervertebral/metabolismo , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Núcleo Pulposo/irrigação sanguínea , Núcleo Pulposo/metabolismo , Prognóstico , Ratos Sprague-Dawley , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo
5.
Soft Matter ; 17(4): 1000-1007, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33284941

RESUMO

The critical adsorption and diffusion of a linear polymer chain on a heterogeneous surface with randomly distributed adsorption sites are studied using dynamic Monte Carlo simulations. Results show that the critical fraction of the adsorption sites at which critical adsorption takes place decreases exponentially with the increasing polymer-surface attraction strength and, at the same time, decreases with the increasing intra-polymer attraction strength. For adsorbed polymers with large intra-polymer attraction strength, we also find an adsorption-induced structural transition from a three-dimensional compact globule to a two-dimensional compacted pancake with an increasing fraction of adsorption sites. Anomalous sub-diffusion is observed for the adsorbed polymer diffusion on heterogeneous surfaces, in contrast to the normal diffusion on a homogeneous surface. The polymer on heterogeneous surfaces shows larger fluctuation in the total surface attraction energy and a longer waiting time.

6.
Soft Matter ; 17(35): 8095-8104, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34525159

RESUMO

The effect of the size of nanoparticles, σNP, on the glass transition temperature, Tg, of polymer nanocomposites is studied by using molecular dynamics simulations. The variation of Tg with σNP shows two distinct behaviours for polymer nanocomposites at low and high volume fractions of nanoparticles (fNP). At a low fNP, Tg decays almost exponentially with σNP, whereas at a high fNPTg shows a complex behaviour: it initially increases and then decreases with increasing σNP. The decrease in Tg with σNP is due to the significant decrease of adsorbed polymer monomers, while the increase in Tg with σNP is attributed to the slower diffusion of larger nanoparticles. We have also investigated the diffusion and relaxation of polymer chains at a temperature above Tg for both low and high fNPs. The diffusion constant and relaxation time of polymer chains are highly consistent with the behaviour of Tg.

7.
Phys Chem Chem Phys ; 23(21): 12216-12225, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34009220

RESUMO

The effect of the loading of nanoparticles on the glass transition temperature, Tg, of polymer nanocomposites is studied by using molecular dynamics simulations. Tg is estimated from the variation of system volume with temperature and the temperature-dependent diffusion of the polymer described by the Vogel-Fulcher-Tammann law. The estimated values of Tg from the two methods are consistent with each other. Results show that Tg can be regulated by changing the volume fraction of nanoparticles, fNP. A novel shift in Tg is observed, that is, Tg increases with fNP at fNP < , while it decreases with increasing fNP at fNP > . The basic mechanism behind the novel shift in Tg is the competition between the attraction of nanoparticles towards polymer chains and the fast diffusion of nanoparticles. The increase in Tg at low fNP is due to the attraction of nanoparticles, whereas the decrease in Tg at high fNP is attributed to the fast diffusion of nanoparticles. The diffusion of the polymer above Tg is also investigated. The diffusion of the polymer decreases with increasing fNP below and increases with fNP above , in agreement with the variation of Tg.

8.
J Shoulder Elbow Surg ; 29(5): 996-1001, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32305108

RESUMO

BACKGROUND: Heterotopic ossification (HO) is a common complication after surgery for elbow trauma. Uric acid is the end product of purine metabolism and has several physiological and pathogenic roles. However, the relationship between HO and uric acid has not been explored. This retrospective study aimed to assess the relationship between HO and serum uric acid (SUA). MATERIAL AND METHODS: We retrospectively reviewed data from 155 patients undergoing elbow trauma surgery in our hospital between January 2013 and December 2018. One hundred patients were included according to the inclusion criteria. They were divided into 2 groups according to the presence or absence of HO, and the SUA level was compared between groups using the independent samples t test. The optimal prognostic cutoff value was obtained using the maximum value of the Youden index. RESULTS: The SUA level was significantly higher in the HO group than in the non-HO group (362.0 ± 87.4 µmol/L vs. 318.3 ± 87.0 µmol/L; P < .05). Using the maximum value of Youden index, 317.5 µmol/L was determined to be the optimal SUA cutoff value for the prediction of HO, with a sensitivity of 68.75% (95% confidence interval [CI], 54.67%-80.05%) and specificity of 55.77% (95% CI, 42.34%-68.40%). CONCLUSIONS: Our study was the first to find that the high SUA level is a risk factor for HO of the elbow joint after trauma. Moreover, 317.5 µmol/L is the SUA threshold predicting the occurrence and development of HO of the elbow, with high sensitivity and specificity.


Assuntos
Articulação do Cotovelo/cirurgia , Cotovelo/cirurgia , Ossificação Heterotópica/sangue , Ossificação Heterotópica/etiologia , Ácido Úrico/sangue , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/etiologia , Prognóstico , Amplitude de Movimento Articular , Estudos Retrospectivos , Fatores de Risco , Sensibilidade e Especificidade , Fatores de Tempo , Adulto Jovem , Lesões no Cotovelo
9.
10.
Heliyon ; 10(11): e32238, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38912455

RESUMO

Background: Intestinal-type gastric adenocarcinoma, representing 95 % of gastric malignancies, originates from the malignant transformation of gastric gland cells. Despite its prevalence, existing methods for prognosis evaluation of this cancer subtype are inadequate. This study aims to enhance patient-specific prognosis evaluation by analyzing the clinicopathological characteristics and prognostic risk factors of intestinal-type gastric adenocarcinoma patients using data from the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute (NCI). Methods: We extracted clinical data for patients diagnosed with intestinal-type gastric adenocarcinoma between 2010 and 2015 from the SEER database, selecting 257 cases based on predefined inclusion and exclusion criteria. Independent risk factors for overall survival (OS) and cancer-specific survival (CSS) were identified using a Cox regression model. A nomogram model for predicting OS or CSS was developed from the Cox risk regression analysis and validated through the consistency index (C-index), ROC curve, and calibration curve. Results: Age, primary tumor resection, chemotherapy, lymph node metastasis, and tumor size were identified as independent prognostic factors for OS and CSS (P < 0.05). The nomogram model, constructed from these indicators, demonstrated superior predictive consistency for OS and CSS compared to the AJCC-TNM staging system. ROC curve analysis confirmed the model's higher accuracy, and calibration curve analysis indicated good agreement between the nomogram's predictions and actual observed outcomes. Conclusion: The nomogram model derived from SEER database analyses accurately predicts OS and CSS for patients with intestinal-type gastric adenocarcinoma. This model promises to facilitate more tailored treatments in clinical practice.

11.
BMC Genomics ; 14: 70, 2013 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-23368971

RESUMO

BACKGROUND: An emerging Hi-C protocol has the ability to probe three-dimensional (3D) architecture and capture chromatin interactions in a genome-wide scale. It provides informative results to address how chromatin organization changes contribute to disease/tumor occurrence and progression in response to stimulation of environmental chemicals or hormones. RESULTS: In this study, using MCF7 cells as a model system, we found estrogen stimulation significantly impact chromatin interactions, leading to alteration of gene regulation and the associated histone modification states. Many chromosomal interaction regions at different levels of interaction frequency were identified. In particular, the top 10 hot regions with the highest interaction frequency are enriched with breast cancer specific genes. Furthermore, four types of E2-mediated strong differential (gain- or loss-) chromosomal (intra- or inter-) interactions were classified, in which the number of gain-chromosomal interactions is less than the number of loss-chromosomal interactions upon E2 stimulation. Finally, by integrating with eight histone modification marks, DNA methylation, regulatory elements regions, ERα and Pol-II binding activities, associations between epigenetic patterns and high chromosomal interaction frequency were revealed in E2-mediated gene regulation. CONCLUSIONS: The work provides insight into the effect of chromatin interaction on E2/ERα regulated downstream genes in breast cancer cells.


Assuntos
Cromossomos Humanos/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Estradiol/farmacologia , Estrogênios/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Genômica , Cromatina/efeitos dos fármacos , Cromatina/genética , Cromatina/metabolismo , Cromossomos Humanos/genética , Cromossomos Humanos/metabolismo , Receptor alfa de Estrogênio/metabolismo , Humanos , Células MCF-7
12.
Genome Res ; 20(6): 733-44, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20442245

RESUMO

The current concept of epigenetic repression is based on one repressor unit corresponding to one silent gene. This notion, however, cannot adequately explain concurrent silencing of multiple loci observed in large chromosome regions. The long-range epigenetic silencing (LRES) can be a frequent occurrence throughout the human genome. To comprehensively characterize the influence of estrogen signaling on LRES, we analyzed transcriptome, methylome, and estrogen receptor alpha (ESR1)-binding datasets from normal breast epithelia and breast cancer cells. This "omics" approach uncovered 11 large repressive zones (range, 0.35 approximately 5.98 megabases), including a 14-gene cluster located on 16p11.2. In normal cells, estrogen signaling induced transient formation of multiple DNA loops in the 16p11.2 region by bringing 14 distant loci to focal ESR1-docking sites for coordinate repression. However, the plasticity of this free DNA movement was reduced in breast cancer cells. Together with the acquisition of DNA methylation and repressive chromatin modifications at the 16p11.2 loci, an inflexible DNA scaffold may be a novel determinant used by breast cancer cells to reinforce estrogen-mediated repression.


Assuntos
Neoplasias da Mama/metabolismo , Cromossomos Humanos Par 16 , Epigênese Genética/fisiologia , Estrogênios/fisiologia , Inativação Gênica , Animais , Sítios de Ligação , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Células Cultivadas , Metilação de DNA , Receptor alfa de Estrogênio/metabolismo , Estrogênios/metabolismo , Feminino , Humanos , Glândulas Mamárias Humanas/citologia , Glândulas Mamárias Humanas/metabolismo , Família Multigênica
13.
J Mol Med (Berl) ; 101(7): 783-799, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37162558

RESUMO

Chaperone-mediated autophagy (CMA) plays multiple roles in cell metabolism. We found that lysosome-associated membrane protein type 2A (LAMP2A), a crucial protein of CMA, plays a key role in the control of mesenchymal stem cell (MSC) adipo-osteogenesis. We identified a differentially expressed CMA gene (LAMP2) in GEO datasets (GSE4911 and GSE494). Further, we performed co-expression analyses to define the relationships between CMA components genes and other relevant genes including Col1a1, Runx2, Wnt3 and Gsk3ß. Mouse BMSCs (mMSCs) exhibiting Lamp2a gene knockdown (LA-KD) and overexpression (LA-OE) were created using an adenovirus system; then we investigated LAMP2A function in vitro by Western blot, Oil Red staining, ALP staining, ARS staining and Immunofluorescence analysis. Next, we used a modified mouse model of tibial fracture to investigate LAMP2A function in vivo. LAMP2A knockdown in mMSCs decreased the levels of osteogenic-specific proteins (COL1A1 and RUNX2) and increased those of the adipogenesis markers PPARγ and C/EBPα; LAMP2A overexpression had the opposite effects. The active-ß-catenin and phospho-GSK3ß (Ser9) levels were upregulated by LAMP2A overexpression and downregulated by LAMP2A knockdown. In the mouse model of tibial fracture, mMSC-overexpressing LAMP2A improved bone healing, as demonstrated by microcomputed tomography and histological analyses. In summary, LAMP2A positively regulates mMSC osteogenesis and suppresses adipo-osteogenesis, probably via Wnt/ß-catenin/GSK3ß signaling. LAMP2A promoted fracture-healing in the mouse model of tibial fracture. KEY MESSAGES: • LAMP2 positively regulates the mBMSCs osteogenic differentiation. • LAMP2 negatively regulates the mBMSCs adipogenic differentiation. • LAMP2 regulates mBMSCs osteogenesis via Wnt/ß-catenin/GSK3ß signaling pathway. • LAMP2 overexpression mBMSCs promote the fracture healing.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Camundongos , Animais , Osteogênese/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Proteínas de Membrana Lisossomal/metabolismo , beta Catenina/genética , beta Catenina/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Microtomografia por Raio-X , Osteoblastos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Diferenciação Celular/fisiologia , Transdução de Sinais , Via de Sinalização Wnt , Células Cultivadas
14.
Clin Nutr ; 42(9): 1715-1727, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37542949

RESUMO

BACKGROUND: An imbalance of osteoblasts (OBs) and osteoclasts (OCs) in a chronic inflammatory microenvironment is an important pathological factor leading to osteoporosis. Eicosapentaenoic acid (EPA) has been shown to suppress inflammation in macrophages and adipocytes. However, the effect of EPA on OBs and OCs has yet to be fully elucidated. AIMS: We explored the roles of EPA in the differentiation of OBs and OCs, as well as the coupling between OBs and OCs in an inflammatory microenvironment. The effects of EPA on estrogen deficiency-induced osteoporosis were also evaluated. METHODS: Mouse bone marrow mesenchymal stem cells (mBMSCs) and mouse bone marrow-derived macrophages (mBMMs) were used for in vitro OBs and OCs differentiation. TNF-α was used to create an inflammatory microenvironment. We examined the effects of EPA on osteoblastogenesis in the absence or presence of TNF-α and collect OBs' culture medium as the conditioned medium (CM). Then we examined the effects of EPA and CM on RANKL-induced osteoclastogenesis. The in vivo effects of EPA were determined using an ovariectomized (OVX) mouse model treated with EPA or vehicle. RESULTS: High-dose EPA was shown to promote osteoblastogenesis in an inflammatory environment in vitro, as well as upregulate expression of OBs-specific proteins and genes. ARS and ALP staining also showed that high-dose EPA-treated groups restored mBMSCs' impaired osteogenic capacity caused by TNFa. Mechanistically, EPA suppressed the NF-κB pathway activated by TNF-α in mBMSCs and rescued TNF-α-mediated inhibition of osteoblastogenesis. EPA was also shown to inhibit expression of RANKL and decrease the RANKL/OPG ratio in OBs in an inflammatory environment. CM from TNF-α-stimulated OBs promoted osteoclastogenesis of mBMMs; EPA-treated CM prevented this. In the OVX mouse model, EPA supplementation prevented bone loss in an estrogen deficiency-induced inflammatory environment. CONCLUSIONS: EPA was demonstrated for the first time to restore mBMSCs' impaired osteogenic capacity caused by TNFa-induced inflammation and rescue the OBs/OCs balance via regulation of RANKL and OPG expression in OBs. EPA showed a remarkable ability to prevent bone loss in OVX mice, suggesting a potential application of EPA in postmenopausal osteoporosis.


Assuntos
Osteoclastos , Osteoporose , Animais , Camundongos , Osteoclastos/metabolismo , Ácido Eicosapentaenoico/farmacologia , Ácido Eicosapentaenoico/uso terapêutico , Fator de Necrose Tumoral alfa/metabolismo , Osteoblastos/metabolismo , Osteoporose/etiologia , Osteoporose/prevenção & controle , Diferenciação Celular , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Suplementos Nutricionais , Estrogênios/metabolismo , Estrogênios/farmacologia , Estrogênios/uso terapêutico
15.
Stem Cell Rev Rep ; 19(4): 968-982, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36609902

RESUMO

BACKGROUND: Epidermal growth factor-like domain protein 7 (EGFL7) is a secreted protein that is differentially expressed in the bone microenvironment; however, the effect of EGFL7 on the osteogenesis of human bone marrow mesenchymal stem cells (hBMSCs) is largely unknown. METHODS: EGFL7 expression in the fracture microenvironment was analyzed based on the Gene Expression Omnibus (GEO) database. Knockdown of EGFL7 by small interfering RNA (siRNA) and in vitro stimulation with recombinant human EGFL7 (rhEGFL7) protein were used to assess alterations in downstream signaling and changes in the osteogenic differentiation and proliferation of hBMSCs. A γ-secretase inhibitor was used to further explore whether inhibition of Notch signaling rescued the osteogenic-inhibitory effect of EGFL7 knockdown in hBMSCs. A femoral defect model was established to verify the effect of recombinant mouse EGFL7 on bone healing in vivo. RESULTS: EGFL7 expression increased during hBMSC osteogenesis. Knockdown of EGFL7 impaired hBMSC osteogenesis and activated Notch1/NICD/Hes1 signaling. rhEGFL7 promoted hBMSC osteogenesis and downregulated Notch1 signaling. The osteoblast-inhibitory effect of EGFL7 knockdown was rescued by Notch1 signaling inhibition. Recombinant EGFL7 led to enhanced bone healing in mice with femoral defects. CONCLUSIONS: EGFL7 promotes osteogenesis of hBMSCs partly via downregulation of Notch1 signaling.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Humanos , Camundongos , Animais , Osteogênese/genética , Regulação para Baixo/genética , Células Cultivadas , Transdução de Sinais , Diferenciação Celular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Osteoblastos/metabolismo , RNA Interferente Pequeno/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição HES-1/genética , Fatores de Transcrição HES-1/metabolismo , Receptor Notch1/genética , Receptor Notch1/metabolismo
16.
Exp Ther Med ; 23(2): 183, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35069864

RESUMO

p-Coumaric acid (PCA) is a phenolic acid that is widely present in numerous plants and human diets. Studies have demonstrated the antioxidant and anti-senescence effects of PCA in different cell types. However, the anti-senescence effects of PCA in nucleus pulposus (NP) cells have remained to be determined. In the present study, reverse transcription-quantitative PCR was used to measure the gene expression of Cyclooxygenase-2 (Cox-2), inducible nitric oxide synthase (iNOS), p53, p16, aggrecan and collagen-2 in NP cells. Immunofluorescence staining was used to evaluate the protein expression of p53, p16 and collagen-2 in NP cells. In addition, cell cycle of NP cells was measured by flow cytometry. ß-galactosidase staining were used to investigate the senescence of NP cells. Preliminary results indicated that PCA suppressed ROS-induced senescence in NP cells via both the p16 and p53 pathways. NP cells were pretreated with PCA at a concentration of 10 or 50 µg/ml prior to stimulation with 200 µM hydrogen peroxide (H2O2). Pretreatment with PCA significantly inhibited H2O2-induced cell cycle arrest in a dose-dependent manner. PCA also reduced the gene expression of Cox-2, iNOS, p53 and p16 induced by H2O2. By contrast, aggrecan and collagen-2 expression in NP cells was upregulated after PCA treatment. Furthermore, PCA suppressed H2O2-induced changes in the protein expression of p16, p53 and collagen-2. H2O2 stimulation of NP cells increased senescence-associated ß-galactosidase (SA-ß-gal) activities, while PCA treatment markedly reversed these SA-ß-gal activities. Collectively, the present results indicated that PCA attenuated H2O2-induced oxidative stress and cellular senescence, suggesting a potential therapeutic utility of PCA in intervertebral disc degeneration.

17.
Front Cell Dev Biol ; 10: 817877, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35198560

RESUMO

Mesenchymal stem cell (MSC) transplantation has been widely used as a potential treatment for a variety of diseases. However, the contradiction between the low survival rate of transplanted cells and the beneficial therapeutic effects has affected its clinical use. Lysosomes as organelles at the center of cellular recycling and metabolic signaling, play essential roles in MSC homeostasis. In the first part of this review, we summarize the role of lysosomal acidification dysfunction in MSC senescence. In the second part, we summarize some of the potential strategies targeting lysosomal proteins to enhance the therapeutic effect of MSCs.

18.
Stem Cell Res Ther ; 13(1): 456, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-36064451

RESUMO

BACKGROUND: The available therapeutic options for large bone defects remain extremely limited, requiring new strategies to accelerate bone healing. Genetically modified bone mesenchymal stem cells (BMSCs) with enhanced osteogenic capacity are recognised as one of the most promising treatments for bone defects. METHODS: We performed differential expression analysis of miRNAs between human BMSCs (hBMSCs) and human dental pulp stem cells (hDPSCs) to identify osteogenic differentiation-related microRNAs (miRNAs). Furthermore, we identified shared osteogenic differentiation-related miRNAs and constructed an miRNA-transcription network. The Forkhead box protein A1 (FOXA1) knockdown strategy with a lentiviral vector was used to explore the role of FOXA1 in the osteogenic differentiation of MSCs. Cell Counting Kit-8 was used to determine the effect of the knockdown of FOXA1 on hBMSC proliferation; real-time quantitative reverse transcription PCR (qRT-PCR) and western blotting were used to investigate target genes and proteins; and alkaline phosphatase (ALP) staining and Alizarin Red staining (ARS) were used to assess ALP activity and mineral deposition, respectively. Finally, a mouse model of femoral defects was established in vivo, and histological evaluation and radiographic analysis were performed to verify the therapeutic effects of FOXA1 knockdown on bone healing. RESULTS: We identified 22 shared and differentially expressed miRNAs between hDPSC and hBMSC, 19 of which were downregulated in osteogenically induced samples. The miRNA-transcription factor interaction network showed that FOXA1 is the most significant and novel osteogenic differentiation biomarker among more than 300 transcription factors that is directly targeted by 12 miRNAs. FOXA1 knockdown significantly promoted hBMSC osteo-specific genes and increased mineral deposits in vitro. In addition, p-ERK1/2 levels were upregulated by FOXA1 silencing. Moreover, the increased osteogenic differentiation of FOXA1 knockdown hBMSCs was partially rescued by the addition of ERK1/2 signalling inhibitors. In a mouse model of femoral defects, a sheet of FOXA1-silencing BMSCs improved bone healing, as detected by microcomputed tomography and histological evaluation. CONCLUSION: These findings collectively demonstrate that FOXA1 silencing promotes the osteogenic differentiation of BMSCs via the ERK1/2 signalling pathway, and silencing FOXA1 in vivo effectively promotes bone healing, suggesting that FOXA1 may be a novel target for bone healing.


Assuntos
Fator 3-alfa Nuclear de Hepatócito , Células-Tronco Mesenquimais , MicroRNAs , Osteogênese , Animais , Células da Medula Óssea , Diferenciação Celular/genética , Células Cultivadas , Fator 3-alfa Nuclear de Hepatócito/genética , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases/genética , Células-Tronco Mesenquimais/metabolismo , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Osteogênese/genética , Osteogênese/fisiologia , Microtomografia por Raio-X
19.
Zhongguo Gu Shang ; 35(8): 799-804, 2022 Aug 25.
Artigo em Zh | MEDLINE | ID: mdl-35979777

RESUMO

Anterior cervical fusion surgery is the first choice for spine surgeons in the treatment of cervical spine diseases. It has significant effects in treating cervical degenerative diseases, trauma and tumors and other cervical diseases. In anterior cervical fusion, it is necessary to use a distractor to properly distract the intervertebral space, so as to fully expose and relieve the compressive factors, restore the physiological height, curvature and stability of the lesion segment, and achieve the best surgical effect. However, there is currently no consensus on the standard distraction height for the intervertebral space during anterior cervical surgery. This article reviewsed the progress of intervertebral space height in anterior cervical fusion from three dimensions:the relationship between intervertebral space height and cervical disc degeneration mechanism, the selection of intervertebral space height during operation, the recovery of intervertebral space height and the postoperative effect, so as to provide theoretical basis and reference for spinal surgeons when performing intervertebral distraction during operation.


Assuntos
Degeneração do Disco Intervertebral , Disco Intervertebral , Fusão Vertebral , Vértebras Cervicais/patologia , Vértebras Cervicais/cirurgia , Humanos , Disco Intervertebral/cirurgia , Pescoço , Resultado do Tratamento
20.
Plant Pathol J ; 38(5): 533-540, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36221925

RESUMO

Thunberg fritillary (Fritillaria thunbergii), a perennial used in traditional Chinese herbal medicine, is a members of the family Liliaceae. The degeneration of germplasm is a severe problem in the production of Fritillaria thunbergii var. chekiangensis. However, no information about viral infections of F. thunbergii var. chekiangensis has been reported. In this study, we sequenced the small RNAs of F. thunbergii var. chekiangensis from leaves and bulbs, and viruses were identified using a phylogenetic analysis and BLAST search for sequence. In addition, multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) was used to rapidly detect viruses in this variety. Our study first reported that five viruses infected F. thunbergii var. chekiangensis. Among them, fritillary virus Y (FVY), lily mottle virus (LMoV), Thunberg fritillary mosaic virus (TFMV), and hop yellow virus (HYV) had been reported in F. thunbergii, while apple stem grooving virus was first reported in the genus Fritillaria. A multiplex RT-PCR method was developed to rapidly test the four viruses FVY, LMoV, TFMV, and HYV in F. thunbergii var. chekiangensis. Our results provide a better understanding of the infection of F. thunbergii var. chekiangensis by viruses and a basic reference for the better design of suitable control measures.

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