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1.
Artigo em Inglês | MEDLINE | ID: mdl-38192148

RESUMO

OBJECTIVE: In recent years, it has been known that mesenchymal stem cells (MSCs) have the potential to treat osteoarthritis (OA). This study aimed to investigate the effects of intraarticular injection of human adipose-derived stem cells (hADSCs) in a new double-damage rabbit osteoarthritis model. METHODS: The OA model was established surgically first by medial collateral ligament and anterior insertional ligament transection and medical meniscectomy, then by articular cartilage full-thickness defect. At six weeks following surgery, hADSCs were labeled with Enhanced Green Fluorescence Protein expressing lentivirus FG12 and injected into the knee joints. All rabbits were sacrificed at 4- and 8 weeks post-surgery. Assessments were carried out by macroscopic examination, immunohistochemistry staining, magnetic resonance imaging, qRT-PCR and ELISA analysis. RESULTS: At 4- and 8 weeks, hADSCs injection showed less cartilage loss, few fissures and few cracks, decreased volume of joint effusion and cartilage defect measured with MRI. Furthermore, ELISA and qRT-PCR methods showed that hADSCs treatment increased the level of IGF-1. CONCLUSIONS: Our data suggest that hADSC transplantation promotes articular cartilage healing in the double-damage rabbit osteoarthritis model, IGF-1 may play an essential role in the hADSC-based cartilage repair process. Transplantation of hADSCs may be suitable for clinical application in the treatment of osteoarthritis.

2.
Curr Osteoporos Rep ; 21(6): 743-749, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37796390

RESUMO

PURPOSE OF REVIEW: Metformin is an anti-glycemic agent, which is widely prescribed to diabetes patients. Although its alleged role on bone strength has been reported for some time, this review focuses primarily on the recent mechanistical insights of metformin on osteocytes, osteoblasts, and osteoclasts. RECENT FINDINGS: Overall, metformin contributed to steering anabolic activity in osteocytes. It caused lower expression in osteocytes of the negative regulators of bone formation sclerostin and DKK1. Likewise, the osteoclastogenesis function of osteoblasts was also skewed towards lower RANKL and higher OPG expressions. Osteoblast lineage cells generally responded to metformin by activating bone formation parameters, such as alkaline phosphatase activity, higher expression of anabolic members of the Wnt pathway, transcription factor Runx2, bone matrix protein proteins, and subsequent mineralization. Metformin affected osteoclast formation and activity in a negative way, reducing the number of multinucleated cells in association with lower expression of typical osteoclast markers and with inhibited resorption. A common denominator studied in all three cell types is its beneficial effect on activating phosphorylated AMP kinase (AMPK) which is associated with the coordination of energy metabolism. Metformin differentially affects bone cells, shifting the balance to more bone formation. Although metformin is a drug prescribed for diabetic patients, the overall bone anabolic effects on osteocytes and osteoblasts and the anti-catabolic effect on osteoclast suggest that metformin could be seen as a promising drug in the bone field.


Assuntos
Metformina , Osteoclastos , Humanos , Osteoclastos/metabolismo , Osteócitos/metabolismo , Metformina/farmacologia , Metformina/uso terapêutico , Metformina/metabolismo , Osteoblastos/metabolismo , Osso e Ossos/metabolismo , Ligante RANK/metabolismo , Diferenciação Celular
3.
J Cancer Res Clin Oncol ; 149(19): 17495-17509, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37902853

RESUMO

PURPOSE: Mitogen-activated protein kinases (MAPK), specifically the c-Jun N-terminal kinase (JNK)-MAPK subfamily, play a crucial role in the development of various cancers, including hepatocellular carcinoma (HCC). However, the specific roles of JNK1/2 and their upstream regulators, MKK4/7, in HCC carcinogenesis remain unclear. METHODS: In this study, we performed differential expression analysis of JNK-MAPK components at both the transcriptome and protein levels using TCGA and HPA databases. We utilized Kaplan-Meier survival plots and receiver operating characteristic (ROC) curve analysis to evaluate the prognostic performance of a risk scoring model based on these components in the TCGA-HCC cohort. Additionally, we conducted immunoblotting, apoptosis analysis with FACS and soft agar assays to investigate the response of JNK-MAPK pathway components to various death stimuli (TRAIL, TNF-α, anisomycin, and etoposide) in HCC cell lines. RESULTS: JNK1/2 and MKK7 levels were significantly upregulated in HCC samples compared to paracarcinoma tissues, whereas MKK4 was downregulated. ROC analyses suggested that JNK2 and MKK7 may serve as suitable diagnostic genes for HCC, and high JNK2 expression correlated with significantly poorer overall survival. Knockdown of JNK1 enhanced TRAIL-induced apoptosis in hepatoma cells, while JNK2 knockdown reduced TNF-α/cycloheximide (CHX)-and anisomycin-induced apoptosis. Neither JNK1 nor JNK2 knockdown affected etoposide-induced apoptosis. Furthermore, MKK7 knockdown augmented TNF-α/CHX- and TRAIL-induced apoptosis and inhibited colony formation in hepatoma cells. CONCLUSION: Targeting MKK7, rather than JNK1/2 or MKK4, may be a promising therapeutic strategy to inhibit the JNK-MAPK pathway in HCC therapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Carcinoma Hepatocelular/genética , Fator de Necrose Tumoral alfa , Etoposídeo , Anisomicina , MAP Quinase Quinase 7/genética , MAP Quinase Quinase 7/metabolismo , Neoplasias Hepáticas/genética , Apoptose
4.
Front Biosci (Landmark Ed) ; 28(2): 26, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36866547

RESUMO

BACKGROUND: The stemness characteristics of cancer cells, such as self-renewal and tumorigenicity, are considered to be responsible, in part, for tumor metastasis. Epithelial-to-mesenchymal transition (EMT) plays an important role in promoting both stemness and tumor metastasis. Although the traditional medicine juglone is thought to play an anticancer role by affecting cell cycle arrest, induction of apoptosis, and immune regulation, a potential function of juglone in regulating cancer cell stemness characteristics remains unknown. METHODS: In the present study, tumor sphere formation assay and limiting dilution cell transplantation assays were performed to assess the function of juglone in regulating maintenance of cancer cell stemness characteristics. EMT of cancer cells was assessed by western blot and transwell assay in vitro, and a liver metastasis model was also performed to demonstrate the effect of juglone on colorectal cancer cells in vivo. RESULTS: Data gathered indicates juglone inhibits stemness characteristics and EMT in cancer cells. Furthermore, we verified that metastasis was suppressed by juglone treatment. We also observed that these effects were, in part, achieved by inhibiting Peptidyl-prolyl cis-trans isomerase NIMA-interacting 1 (Pin1). CONCLUSIONS: These results indicate that juglone inhibits maintenance of stemness characteristics and metastasis in cancer cells.


Assuntos
Transição Epitelial-Mesenquimal , Naftoquinonas , Neoplasias , Células-Tronco Neoplásicas , Apoptose , Western Blotting , Neoplasias/tratamento farmacológico , Metástase Neoplásica/prevenção & controle , Naftoquinonas/farmacologia
5.
Biochem Biophys Res Commun ; 646: 70-77, 2023 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-36706708

RESUMO

Once prostate cancer (PC) metastasizes towards bone the 5-year survival rates drop with 70%, but it is largely unknown why. Bone is continuously mechanically loaded, which likely modulates the paracrine signaling from osteocytes towards PC cells to affect tumor behavior. We hypothesize that shear loaded osteocytes affect PC cell proliferation, invasion and epithelial and mesenchymal-related gene and protein expression. We cultured human DU145 cells, a commonly used cell line for prostate cancer metastases, in the conditioned medium (CM) from shear loaded or unloaded human osteocyte-like-cells (OCYLCs) for 1 and 3 days and assessed their number by staining nuclei with DAPI, their invasion by performing an invasion assay, and epithelial-to-mesenchymal (EMT)-related gene and protein expression by qPCR and immunocytochemistry. CM of shear loaded OCYLCs did not affect DU145 cell number compared to CM of static cultured OCYLCs, but decreased their invasion 1.34-fold. CM of shear loaded OCYLCs enhanced expression of epithelial genes: SYND1 and CDH1 after day 1, while it also enhanced CDH1 after day 3. CM of shear loaded osteocytes enhanced mesenchymal genes: VMN, Snail and MIP2 after day 1, while it decreased expression of mesenchymal CYR61 after day 3. We conclude that CM of shear loaded OCYLCs does not affect DU145 cell proliferation, but decreases their invasion, and differentially affects their EMT-related gene expression. Identifying paracrine signals from shear loaded osteocytes that decrease PC cell invasion may provide novel leads in developing treatments for bone metastases from PC.


Assuntos
Osteócitos , Neoplasias da Próstata , Masculino , Humanos , Osteócitos/metabolismo , Linhagem Celular , Neoplasias da Próstata/patologia , Proliferação de Células , Expressão Gênica , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Invasividade Neoplásica
6.
Plant J ; 113(2): 387-401, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36471650

RESUMO

Formate dehydrogenase (FDH; EC 1.2.1.2.) has been implicated in plant responses to a variety of stresses, including aluminum (Al) stress in acidic soils. However, the role of this enzyme in Al tolerance is not yet fully understood, and how FDH gene expression is regulated is unknown. Here, we report the identification and functional characterization of the tomato (Solanum lycopersicum) SlFDH gene. SlFDH encodes a mitochondria-localized FDH with Km values of 2.087 mm formate and 29.1 µm NAD+ . Al induced the expression of SlFDH in tomato root tips, but other metals did not, as determined by quantitative reverse transcriptase-polymerase chain reaction. CRISPR/Cas9-generated SlFDH knockout lines were more sensitive to Al stress and formate than wild-type plants. Formate failed to induce SlFDH expression in the tomato root apex, but NAD+ accumulated in response to Al stress. Co-expression network analysis and interaction analysis between genomic DNA and transcription factors (TFs) using PlantRegMap identified seven TFs that might regulate SlFDH expression. One of these TFs, SlSTOP1, positively regulated SlFDH expression by directly binding to its promoter, as demonstrated by a dual-luciferase reporter assay and electrophoretic mobility shift assay. The Al-induced expression of SlFDH was completely abolished in Slstop1 mutants, indicating that SlSTOP1 is a core regulator of SlFDH expression under Al stress. Taken together, our findings demonstrate that SlFDH plays a role in Al tolerance and reveal the transcriptional regulatory mechanism of SlFDH expression in response to Al stress in tomato.


Assuntos
Solanum lycopersicum , Solanum lycopersicum/genética , NAD/metabolismo , Alumínio/toxicidade , Alumínio/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Formiatos/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
7.
Int J Mol Sci ; 23(3)2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35163057

RESUMO

Low phosphate (Pi) availability and high aluminum (Al) toxicity constitute two major plant mineral nutritional stressors that limit plant productivity on acidic soils. Advances toward the identification of genes and signaling networks that are involved in both stresses in model plants such as Arabidopsis thaliana and rice (Oryza sativa), and in other plants as well have revealed that some factors such as organic acids (OAs), cell wall properties, phytohormones, and iron (Fe) homeostasis are interconnected with each other. Moreover, OAs are involved in recruiting of many plant-growth-promoting bacteria that are able to secrete both OAs and phosphatases to increase Pi availability and decrease Al toxicity. In this review paper, we summarize these mutual mechanisms by which plants deal with both Al toxicity and P starvation, with emphasis on OA secretion regulation, plant-growth-promoting bacteria, transcription factors, transporters, hormones, and cell wall-related kinases in the context of root development and root system architecture remodeling that plays a determinant role in improving P use efficiency and Al resistance on acidic soils.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Bactérias/crescimento & desenvolvimento , Oryza/crescimento & desenvolvimento , Fosfatos/deficiência , Arabidopsis/metabolismo , Arabidopsis/microbiologia , Bactérias/metabolismo , Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Ferro/metabolismo , Oryza/metabolismo , Oryza/microbiologia , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia
8.
Materials (Basel) ; 15(3)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35160896

RESUMO

The effect of microstructure on the onset strain and rate of deformation-induced martensitic transformation (DIMT) in Q&P steel is studied by a mean-field micromechanics model, in which the residual austenite (RA) and primary martensite (M) phases are treated as elastoplastic particles embedded into the ferrite (F) matrix. The results show that when the volume fraction of the RA increases with a constant fraction of the M, the onset strain of DIMT increases and transformation rate decreases, in contrast to the case of the RA fraction effect with a fixed F fraction. Increasing the volume fraction of the M postpones the DIMT, regardless of the corresponding change from the RA or F fraction, which is similar to the effect of the RA fraction with the constant M but to a higher degree. Conversely, when increasing the fraction of the matrix F, the onset strain of DIMT increases and the rate decreases, and the effect is greater when the corresponding fraction change comes from the M rather than from the RA. Moreover, when the aspect ratio of the RA increases, the onset strain of DIMT decreases with a gradual increase in transformation rate, in agreement with the experimental observation that the equiaxial austenite is more stable in Q&P steels. However, the aspect ratio effect of the M is opposite to that of the RA, indicating that the lath-shaped primary martensite could protect the austenite from DIMT.

9.
Acta Biochim Biophys Sin (Shanghai) ; 54(12): 1889-1896, 2022 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-36789689

RESUMO

Colorectal cancer (CRC) is a malignant tumor with a high incidence and mortality worldwide. Currently, the underlying molecular mechanisms of CRC are still unclear. Zinc finger protein 3 (ZNF3) is a zinc-finger transcription factor that has been reported as a candidate for breast cancer prognosis, suggesting its involvement in the regulation of tumorigenesis. However, the association between ZNF3 and CRC remains unknown. To investigate the role of ZNF3 in CRC, we first analyze the correlation between ZNF3 expression and CRC, and the results demonstrate that ZNF3 is highly expressed in CRC tissue and cells, which is associated with the age of CRC patients. In vitro studies show that ZNF3 overexpression promotes CRC cell migration. Compared to control cells, knockdown of ZNF3 markedly suppresses CRC cell proliferation, migration and invasion and promotes G0/G1 phase cell cycle arrest. The expressions of the EMT-related markers TWIST and MMP1 are significantly decreased when ZNF3 is silenced. Additionally, overexpression of MMP1 and TWIST exacerbates CRC cell proliferation, accelerates the S phase cell cycle in ZNF3-knockdown SW480 cells, and increases cell migration and invasion through Transwell chambers. These data suggest that ZNF3 is involved in cellular proliferation, migration and invasion by regulating MMP1 and TWIST in CRC cells.


Assuntos
Neoplasias Colorretais , Metaloproteinase 1 da Matriz , Invasividade Neoplásica , Fatores de Transcrição , Humanos , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transformação Celular Neoplásica , Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Dedos de Zinco , Proteína 1 Relacionada a Twist/genética , Proteína 1 Relacionada a Twist/metabolismo
10.
Gigascience ; 10(3)2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33739402

RESUMO

BACKGROUND: The spider Trichonephila antipodiana (Araneidae), commonly known as the batik golden web spider, preys on arthropods with body sizes ranging from ∼2 mm in length to insects larger than itself (>20‒50 mm), indicating its polyphagy and strong dietary detoxification abilities. Although it has been reported that an ancient whole-genome duplication event occurred in spiders, lack of a high-quality genome has limited characterization of this event. RESULTS: We present a chromosome-level T. antipodiana genome constructed on the basis of PacBio and Hi-C sequencing. The assembled genome is 2.29 Gb in size with a scaffold N50 of 172.89 Mb. Hi-C scaffolding assigned 98.5% of the bases to 13 pseudo-chromosomes, and BUSCO completeness analysis revealed that the assembly included 94.8% of the complete arthropod universal single-copy orthologs (n = 1,066). Repetitive elements account for 59.21% of the genome. We predicted 19,001 protein-coding genes, of which 96.78% were supported by transcriptome-based evidence and 96.32% matched protein records in the UniProt database. The genome also shows substantial expansions in several detoxification-associated gene families, including cytochrome P450 mono-oxygenases, carboxyl/cholinesterases, glutathione-S-transferases, and ATP-binding cassette transporters, reflecting the possible genomic basis of polyphagy. Further analysis of the T. antipodiana genome architecture reveals an ancient whole-genome duplication event, based on 2 lines of evidence: (i) large-scale duplications from inter-chromosome synteny analysis and (ii) duplicated clusters of Hox genes. CONCLUSIONS: The high-quality T. antipodiana genome represents a valuable resource for spider research and provides insights into this species' adaptation to the environment.


Assuntos
Aranhas , Animais , Cromossomos , Duplicação Gênica , Genoma , Genômica , Humanos , Aranhas/genética
11.
Comput Biol Med ; 124: 103826, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32798924

RESUMO

Fluid flow dynamics and oxygen-concentration in 3D-printed scaffolds within perfusion bioreactors are sensitive to controllable bioreactor parameters such as inlet flow rate. Here we aimed to determine fluid flow dynamics, oxygen-concentration, and cell proliferation and distribution in 3D-printed scaffolds as a result of different inlet flow rates of perfusion bioreactors using experiments and finite element modeling. Pre-osteoblasts were treated with 1 h pulsating fluid flow with low (0.8 Pa; PFFlow) or high peak shear stress (6.5 Pa; PFFhigh), and nitric oxide (NO) production was measured to validate shear stress sensitivity. Computational analysis was performed to determine fluid flow between 3D-scaffold-strands at three inlet flow rates (0.02, 0.1, 0.5 ml/min) during 5 days. MC3T3-E1 pre-osteoblast proliferation, matrix production, and oxygen-consumption in response to fluid flow in 3D-printed scaffolds inside a perfusion bioreactor were experimentally assessed. PFFhigh more strongly stimulated NO production by pre-osteoblasts than PFFlow. 3D-simulation demonstrated that dependent on inlet flow rate, fluid velocity reached a maximum (50-1200 µm/s) between scaffold-strands, and fluid shear stress (0.5-4 mPa) and wall shear stress (0.5-20 mPa) on scaffold-strands surfaces. At all inlet flow rates, gauge fluid pressure and oxygen-concentration were similar. The simulated cell proliferation and distribution, and oxygen-concentration data were in good agreement with the experimental results. In conclusion, varying a perfusion bioreactor's inlet flow rate locally affects fluid velocity, fluid shear stress, and wall shear stress inside 3D-printed scaffolds, but not gauge fluid pressure, and oxygen-concentration, which seems crucial for optimized bone tissue engineering strategies using bioreactors, scaffolds, and cells.


Assuntos
Reatores Biológicos , Impressão Tridimensional , Engenharia Tecidual , Alicerces Teciduais , Baías , Perfusão
12.
Oncol Res ; 27(6): 643-651, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-30764900

RESUMO

Heme oxygenase-1 (HO-1) plays an important role in the progression of several malignancies including breast cancer. However, its role in breast cancer metastasis is still ambiguous. In this study, we observed the effect of HO-1 on mouse mammary carcinoma metastasis using the in vivo tumor metastasis model. Our results revealed that overexpression of HO-1 strongly inhibits the lung metastasis of 4T1 cells. In in vitro analysis, associated indices for epithelial-mesenchymal transition (EMT), migration, and proliferation of 4T1 cells were evaluated. The results show that HO-1 inhibits EMT, migration, and proliferation of 4T1 cells. In addition, the Notch1/Slug pathway is found to mediate an antimetastasis role of HO-1 in mouse mammary carcinoma. In conclusion, since HO-1/Notch1/Slug axis plays an important role in breast cancer metastasis, induction of HO-1 could be used as a potential therapeutic strategy for breast cancer treatment.


Assuntos
Heme Oxigenase-1/metabolismo , Receptor Notch1/metabolismo , Transdução de Sinais , Animais , Movimento Celular , Proliferação de Células , Modelos Animais de Doenças , Transição Epitelial-Mesenquimal/genética , Feminino , Expressão Gênica , Heme Oxigenase-1/genética , Xenoenxertos , Neoplasias Pulmonares/secundário , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos , Receptor Notch1/genética
13.
Zhongguo Gu Shang ; 31(9): 835-839, 2018 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-30332877

RESUMO

OBJECTIVE: To determine the association of sarcopenia with short-term postoperative function after hip replacement for femoral neck fractures. METHODS: A prospective study of 181 consecutive patients with femoral neck fractures who underwent hip replacement from May 2014 to January 2017 were performed, including 58 males and 123 females aging from 53 to 92 years old. The general conditions were collected before surgery, skeletal muscle index(ASMI), handgrip strength were measured. Clinical outcomes were followed up including postoperative complications, time of on-site, Harris score (postoperative 2 weeks, 3, 6 months), hospitalization costs, and hospital stay. According to handgrip strength and ASMI, the patients were divided into the sarcopina group and the non-sarcopina group; according to the Harris score at the 6-month follow-up, the patients were divided into good prognosis group and poor prognosis group. Univariate analysis and binary logistic regression analysis were used to investigate whether sarcopenia was a risk factor for poor postoperative hip joint surgery. RESULTS: All patients were followed up at 2 weeks, 3 and 6 months, postoperative early complication included wound infection in 16 cases, thrombus of lower extremity veins in 14 cases, no dislocation, prosthetic loosening and prosthesis related infections occurred. Sarcopenia was present in 82 of 181 patients(45%), Compared with non-sarcopenic patients, sarcopenic patients had a higher risk of postoperative complications, longer postoperative hospital stay, more hospital costs and lower harris scores. In Binary logistic analysis revealed that sarcopenia(P=0.08), hemiarthroplasty(P<0.001), diabetes(P=0.016) and infection(P=0.018) were important predictors of unsatisfactory postoperative function. CONCLUSIONS: Sarcopenia is an important predictor of poor postoperative prognosis in patients with femoral neck fractures after hip replacement. The treatment for sarcopenia maybe an important way to protect patients with femoral neck fractures from poor prognosis after hip replacement.


Assuntos
Artroplastia de Quadril , Fraturas do Colo Femoral , Sarcopenia , Idoso , Idoso de 80 Anos ou mais , Feminino , Força da Mão , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
14.
Macromol Biosci ; 18(9): e1700424, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29931763

RESUMO

Critical-sized bone defects are incapable of self-healing and are commonly seen in clinical practice. The authors explore a new treatment for this, decellularized periosteum is applied to chitosan globules (chitosan-DP globules) as a hybrid material. The efficacy of chitosan-DP globules on rabbit femoral condyle bone defects is assessed with biocompatibility, biomechanics, and osteogenic efficiency measurements, and compared with the results of chitosan globules and empty control. No difference in cytotoxicity is observed among chitosan-DP globules, chitosan globules, and the empty control. Chitosan-DP globules possesse a better surface for cell adhesion than did chitosan globules. Chitosan-DP globules demonstrate superior efficiency for osteogenesis in the defect area compared to chitosan globules as per microcomputed tomography examination and push-out testing, with relatively minor histological differences. Both chitosan globule groups show more satisfactory results than those for the empty control. The results implicate chitosan-DP globules as a promising solution for bone defects.


Assuntos
Materiais Biocompatíveis/farmacologia , Regeneração Óssea/efeitos dos fármacos , Quitosana/farmacologia , Fêmur/patologia , Periósteo , Animais , Materiais Biocompatíveis/química , Fenômenos Biomecânicos , Regeneração Óssea/fisiologia , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Quitosana/farmacocinética , Fêmur/lesões , Células-Tronco Mesenquimais/efeitos dos fármacos , Peso Molecular , Coelhos , Propriedades de Superfície , Microtomografia por Raio-X
15.
Int J Nanomedicine ; 12: 4209-4224, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28652728

RESUMO

Surface modification of titanium (Ti) implants are extensively studied in order to obtain prominent biocompatibility and antimicrobial activity, especially preventing implant-associated infection. In this study, Ti substrates surface were modified by graphene oxide (GO) thin film and silver (Ag) nanoparticles via electroplating and ultraviolet reduction methods so as to achieve this purpose. Microstructures, distribution, quantities and spectral peaks of GO and Ag loading on the Ti sheets surface were characterized. GO-Ag-Ti multiphase nanocomposite exhibited excellent antimicrobial ability and anti-adherence performance. Subsequently, morphology, membrane integrity, apoptosis and relative genes expression of bacteria incubated on the Ti samples surface were monitored to reveal the bactericidal mechanism. Additionally, the cytotoxicity of Ti substrates incorporating GO thin film and Ag nanoparticles were investigated. GO-Ag-Ti composite configuration that have outstanding antibacterial properties will provide the foundation to study bone integration in vitro and in vivo in the future.


Assuntos
Antibacterianos/farmacologia , Grafite/química , Nanocompostos/química , Prata/farmacologia , Titânio/química , Animais , Antibacterianos/administração & dosagem , Antibacterianos/química , Aderência Bacteriana/efeitos dos fármacos , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos/métodos , Grafite/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Porphyromonas gingivalis/efeitos dos fármacos , Ratos , Prata/química , Staphylococcus aureus/efeitos dos fármacos , Streptococcus mutans/efeitos dos fármacos , Propriedades de Superfície , Titânio/farmacologia
16.
Acta Biomater ; 54: 175-185, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28315494

RESUMO

The topography of biomaterials can significantly influence the osteogenic differentiation of cells. Understanding topographical signal transduction is critical for developing biofunctional surfaces, but the current knowledge is insufficient. Recently, numerous reports have suggested that the unfolded protein response (UPR) and osteogenic differentiation are inter-linked. Therefore, we hypothesize that the UPR pathway may be involved in the topography-induced osteogenesis. In the present study, different surface topographies were fabricated on pure titanium foils and the endoplasmic reticulum (ER) stress and UPR pathway were systematically investigated. We found that ER stress and the PERK-eIF2α-ATF4 pathway were activated in a time- and topography-dependent manner. Additionally, the activation of the PERK-eIF2α-ATF4 pathway by different topographies was in line with their osteogenic induction capability. More specifically, the osteogenic differentiation could be enhanced or weakened when the PERK-eIF2α-ATF4 pathway was promoted or inhibited, respectively. Furthermore, tuning of the degree of ER stress with different concentrations of thapsigargin revealed that mild ER stress promotes osteogenic differentiation, whereas excessive ER stress inhibits osteogenic differentiation and causes apoptosis. Taken together, our findings suggest that the UPR may play a critical role in topography-induced osteogenic differentiation, which may help to provide new insights into topographical signal transduction. STATEMENT OF SIGNIFICANCE: Suitable implant surface topography can effectively improve bioactivity and eventual bone affinity. However, the mechanism of topographical signaling transduction is unclear and criteria for designation of an appropriate implant surface topography is lacking. This study shows that the ER stress and PERK-eIF2α-ATF4 pathway were activated by micro- and micro/nano-topographies, which is corresponding to the osteogenic induction abilities of these topographies. Furthermore, we have found that mild ER stress improves osteogenic differentiation, whereas excessive ER stress inhibits osteogenic differentiation and causes apoptosis. Our findings demonstrate that the UPR plays a critical role in the topography induced osteogenic differentiation, which may help to provide new insights into the topographical signaling transduction.


Assuntos
Células da Medula Óssea/metabolismo , Diferenciação Celular , Células-Tronco Mesenquimais/metabolismo , Osteogênese , Transdução de Sinais , Resposta a Proteínas não Dobradas , Animais , Células da Medula Óssea/citologia , Estresse do Retículo Endoplasmático , Células-Tronco Mesenquimais/citologia , Ratos , Ratos Sprague-Dawley
17.
Biochem Biophys Res Commun ; 481(1-2): 169-175, 2016 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-27810363

RESUMO

Heme oxygenase (HO) is the rate-limiting enzyme in heme metabolism. HO-1 exhibits anti-oxidative and anti-inflammatory function via the actions of its metabolite, respectively. A growing body of evidence demonstrates that HO-1 is implicated in the pathogenesis and progression of several types of cancer. However, whether HO-1 takes part in healthy-premalignant-malignant transformation is still undefined. In this study, we took advantage of transgenic mice which over-expressed HO-1 dominant negative mutant (HO-1 G143H) and observed its susceptibility to DEN-induced hepatocarcinogenesis. Our results indicate that HO-1 G143H mutant accelerates the progression of tumorigenesis and tumor growth. The mechanism is closely related to enhancement of ROS production which induce more hepatocytes death and secretion of inflammatory cytokines, proliferation of surviving hepatocytes. Our result provides the direct evidence that HO-1 plays an important protective role in liver carcinogenesis. Alternatively, we suggest the possible explanation on effect of HO-1 promoter polymorphism which involved in tumorigenesis.


Assuntos
Carcinogênese/genética , Dietilnitrosamina , Heme Oxigenase-1/genética , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/genética , Proteínas de Membrana/genética , Animais , Carcinógenos , Neoplasias Hepáticas/enzimologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação/genética , Regiões Promotoras Genéticas/genética
18.
Oncol Rep ; 36(5): 2715-2722, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27571925

RESUMO

Heme metabolism system is involved in microRNA (miRNA) biogenesis. The complicated interplay between heme oxygenase-1 (HO-1) and miRNA has been observed in various tissues and diseases, including human malignancy. In the present study, our data showed that stable HO-1 overexpression in hepatocellular carcinoma (HCC) cells downregulated several oncomiRs. The most stably downregulated are miR-30d and miR-107. Iron, one of HO-1 catalytic products, was an important mediator in this regulation. Cell function analysis demonstrated that HO-1 inhibited the proliferation and metastasis of HepG2 cells, whereas miR-30d/miR-107 improved the proliferative and migratory ability of HepG2 cells. The beneficial effect of HO-1 in HCC inhibition could be reversed by upregulating miR-30d and miR-107. Akt and ERK pathways may be involved in the regulation of HO-1/miR-30d/miR-107 in HCC. These data indicate that HO-1 significantly suppresses HCC progression by regulating the miR-30d/miR-107 level, suggesting miR-30d/miR-107 regulation as a new molecular mechanism of HO-1 anticancer effect.


Assuntos
Carcinoma Hepatocelular/genética , Heme Oxigenase-1/biossíntese , Neoplasias Hepáticas/genética , MicroRNAs/genética , Carcinoma Hepatocelular/patologia , Proliferação de Células/genética , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Heme Oxigenase-1/genética , Células Hep G2 , Humanos , Neoplasias Hepáticas/patologia , MicroRNAs/biossíntese , Transdução de Sinais
19.
Oncotarget ; 7(1): 266-78, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26497556

RESUMO

MicroRNAs (miRNAs) are dysregulated in many types of malignancies, including human hepatocellular carcinoma (HCC). MiR-107 has been implicated in several types of cancer regulation; however, relatively little is known about miR-107 in human HCC. In the present study, we showed that the overexpression of miR-107 accelerates the tumor progression of HCC in vitro and in vivo through its new target gene, CPEB3. Furthermore, our results demonstrated that CPEB3 is a newly discovered tumor suppressor that acts via the EGFR pathway. Therefore, our study demonstrates that the newly discovered miR-107/CPEB3/EGFR axis plays an important role in HCC progression and might represent a new potential therapeutic target for HCC treatment.


Assuntos
Carcinoma Hepatocelular/genética , Receptores ErbB/genética , Neoplasias Hepáticas/genética , MicroRNAs/genética , Proteínas de Ligação a RNA/genética , Regiões 3' não Traduzidas/genética , Animais , Western Blotting , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Progressão da Doença , Receptores ErbB/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica , Interferência de RNA , Proteínas de Ligação a RNA/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transplante Heterólogo , Carga Tumoral/genética
20.
Biomed Mater ; 10(1): 015001, 2014 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-25534679

RESUMO

Postoperative infections remain a risk factor that leads to failures in oral and maxillofacial artificial bone transplantation. This study aimed to synthesize and evaluate a novel hydroxyapatite whisker (HAPw) / nano zinc oxide (n-ZnO) antimicrobial bone restorative biomaterial. A scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and x-ray diffraction (XRD) were employed to characterize and analyze the material. Antibacterial capabilities against Staphylococcus aureus, Escherichia coli, Candida albicans and Streptococcus mutans were determined by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), and kinetic growth inhibition assays were performed under darkness and simulated solar irradiation. The mode of antibiotic action was observed by transmission electron microscopy (TEM) and confocal laser scanning microscopy (CLSM). The MIC and MBC were 0.078-1.250 mg ml(-1) and 0.156-2.500 mg ml(-1), respectively. The inhibitory function on the growth of the microorganisms was achieved even under darkness, with gram-positive bacteria found to be more sensitive than gram-negative, and enhanced antimicrobial activity was exhibited under simulated solar excitation compared to darkness. TEM and CLSM images revealed a certain level of bacterial cell membrane destruction after treatment with 1 mg ml(-1) of the material for 12 h, causing the leakage of intracellular contents and bacteria death. These results suggest favorable antibiotic properties and a probable mechanism of the biomaterial for the first time, and further studies are needed to determine its potential application as a postoperative anti-inflammation method in bone transplantation.


Assuntos
Anti-Infecciosos/química , Materiais Biocompatíveis/química , Durapatita/química , Nanoestruturas/química , Óxido de Zinco/química , Anti-Inflamatórios/química , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Candida albicans/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/química , Inflamação/tratamento farmacológico , Luz , Testes de Sensibilidade Microbiana , Microscopia Confocal , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanocompostos , Oxigênio/química , Polietilenoglicóis/química , Pós , Staphylococcus aureus/efeitos dos fármacos , Streptococcus mutans/efeitos dos fármacos , Temperatura , Difração de Raios X
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