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1.
Restor Neurol Neurosci ; 38(1): 41-54, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31683491

RESUMO

BACKGROUND: Dry-electrode-based transcranial direct current stimulation is a new type of non-invasive brain stimulation system which relieves chronic low back pain and improves related muscle movement, in a way that overcomes the drawback of conventional systems. OBJECTIVE: To investigate the effectiveness of dry-electrode-based transcranial direct current stimulation in relieving chronic low back pain and altering pain-related low back muscles movement, by using pain assessment tool and surface electromyographic topography. METHODS: We conducted a prospective, double-blind, randomized, sham-controlled study. 60 patients with non-specific chronic low back pain were randomly and evenly allocated into tDCS and sham groups. Each group accepted a single 20-minute stimulation at 2 mA on the primary motor cortex. Numeric rating scale for pain intensity assessment and root-mean-square difference parameter from surface electromyographic topography were measured before and after stimulation. The current direction in brain using finite element method was simulated to verify the current distribution under dry stimulation electrode. RESULTS: After stimulation, the pain intensity in the tDCS group significantly decreased, while it did not show evident change in the sham group. However, change of root-mean-square difference parameters between tDCS and sham groups showed no significant difference. Simulation results based on finite element method showed most of current focused on primary motor cortex while peak value of current density was 0.225 A/m2. CONCLUSIONS: Dry-electrode-based transcranial direct current stimulation can lower pain perception in patients with chronic low back pain. The analgesic mechanism can affect the top-down modulation pathway of pain.

2.
Arthritis Res Ther ; 21(1): 300, 2019 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-31870428

RESUMO

INTRODUCTION: Osteoarthritis (OA) is an inflammatory disease of the joints that causes progressive disability in the elderly. Reactive oxygen species (ROS) play an important role in OA development; they may activate the NLRP3 inflammasome, thereby inducing the secretion of proinflammatory IL-1ß and IL-18, leading to the aggravation of the downstream inflammatory response. Nrf2 is a key transcription factor that regulates the expression of antioxidant enzymes that protect against oxidative stress and tissue damage. We aimed to explore the underlying mechanism of OA development by investigating NLRP3, ASC, Nrf2, and HO-1 expression in synovia and their regulatory networks in OA. METHODS: Human total knee replacement samples were subjected to histology and micro-CT analysis to determine the pathological changes in the cartilage and subchondral bone and to assess the expression of inflammation-related markers in the synovial tissue by immunohistochemistry (IHC), qRT-PCR, and Western blot. To investigate these pathological changes in an OA animal model, adult Sprague-Dawley rats were subjected to anterior cruciate ligament transection and medial meniscectomy. Articular cartilage and subchondral bone changes and synovial tissue were also determined by the same methods used for the human samples. Finally, SW982 cells were stimulated with lipopolysaccharide (LPS) as an in vitro inflammatory cell model. The correlation between NLRP3 and Nrf2 expression was confirmed by knocking down NLRP3 or Nrf2. RESULTS: Cartilage destruction and subchondral bone sclerosis were found in the OA patients and OA model rats. Significantly increased expression levels of NLRP3, ASC, Nrf2, and HO-1 were found in the synovial tissue from OA patients. NLRP3, ASC, Nrf2, and HO-1 expression in the synovium was also upregulated in the OA group compared with the sham group. Furthermore, the NLRP3, Nrf2, HO-1, IL-1ß, and IL-18 expression in LPS-treated SW982 cells was increased in a dose-dependent manner. As expected, the expression of NLRP3 was upregulated, and the expression of IL-1ß and IL-18 was downregulated after Nrf2 silencing. However, knocking down NLRP3 did not affect the expression of Nrf2. CONCLUSIONS: ROS-induced oxidative stress may be the main cause of NLRP3 inflammasome activation and subsequent release of downstream factors during OA development. Nrf2/HO-1 signaling could be a key pathway for the activation of the NLRP3 inflammasome, which may contribute to the progression of OA. Herein, we discovered a novel role of Nrf2/HO-1 signaling in the production of NLRP3, which may facilitate the prevention and treatment of OA.

3.
Int J Biol Macromol ; 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31751710

RESUMO

Osteoporosis is the most widespread metabolic bone disease characterized by decreased bone mass and bone quality, and its diagnosis and treatment remains challenging. To date, medicinal plants have received increasing attention from researchers for researching effective and less toxic therapeutic ingredients, including polysaccharide, to treat osteoporosis. The present study aims to evaluate the osteoprotective effects of a polysaccharide (EBP) from Epimedium brevicornum in glucocorticoid-induced osteoporosis in vitro and investigate the underlying mechanism. EBP (25 and 100 µg/ml) pretreatment could significantly prevent decreased cell proliferation of osteoblasts (OBs) treated only with 100 µM of dexamethasone (Dex) via induction of apoptosis. The osteoblastic differentiation of EBP pretreatment on OBs at early and later phase was further confirmed by the increased alkaline phosphatase (ALP) activity and calcium content, respectively. Meanwhile, the increased expression of cleaved caspase-3 and Bax, as well as a decrease of Bcl-2 and the phosphorylation of PI3K, Akt and mTOR protein in Dex-treated OBs were totally reversed by EBP pretreatment. Moreover, the protein expression of Lrp-5, ß-catenin, Runx2 and Osx were significantly up-regulated in the presence of EBP pretreatment. In conclusion, these results demonstrated that EBP pretreatment may be a potential therapeutic agent for patients with glucocorticoid-induced osteoporosis (GIO).

4.
J Biol Chem ; 294(38): 14096-14104, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31366731

RESUMO

Understanding the mechanism of how liver ductal cells (cholangiocytes) differentiate into hepatocytes would permit liver-regenerative medicine. Emerging liver ductal organoids provide an ex vivo system to investigate cholangiocyte-to-hepatocyte differentiation. However, as current gene manipulation methods require organoid dissociation into single cells and have only low efficiency, it is difficult to dissect specific gene functions in these organoids. Here we developed the adeno-associated virus (AAV) vector AAV-DJ as a powerful tool to transduce mouse and human liver ductal organoids. Via AAV-DJ-mediated up- or down-regulation of target genes, we successfully manipulated cholangiocyte-to-hepatocyte differentiation. We induced differentiation by overexpressing the hepatocyte-specifying regulator hepatocyte nuclear factor 4α (HNF4α) and blocked differentiation by stimulating Notch signaling or interfering with Smad signaling. Further screening for transcriptional factors critical for cholangiocyte-to-hepatocyte differentiation identified HOP homeobox (HOPX), T-box 15 (TBX15), and transcription factor CP2-like 1 (TFCP2L1) as master regulators. We conclude that this highly efficient and convenient gene manipulation system we developed could facilitate investigation into genes involved in cell lineage transitions and enable application of engineered organoids in regenerative medicine.

6.
J Nat Med ; 73(1): 104-113, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30218208

RESUMO

Osteoporosis is characterized by low bone mass and the degeneration of bone structure, conditions which increase the risk of fracture. Aloin has been shown to affect bone metabolism, but its role in osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) remains unclear. The aim of our study was to determine whether aloin promotes the proliferation and osteogenic differentiation of BMSCs and, if so, whether it acts via activation of the ERK1/2-Runx2 signaling pathway. We found that the different concentrations of aloin tested had no obvious cytotoxic effects on the viability of BMSCs. Under osteogenic induction conditions, aloin increased cellular alkaline phosphatase activity, promoted BMSC mineralization, and increased osteogenic-related gene expression. In addition, treating the BMSCs with the signal transduction inhibitor PD98059 (ERK1/2) effectively attenuated Runx2 activation in these cells and also suppressed osteoblastic differentiation. Overall, our study demonstrates that aloin promotes osteogenic differentiation of BMSCs through activation of the ERK1/2-Runx2 signaling pathway.


Assuntos
Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Emodina/análogos & derivados , Células-Tronco Mesenquimais/citologia , Osteogênese/efeitos dos fármacos , Transdução de Sinais , Animais , Medula Óssea , Diferenciação Celular , Células Cultivadas , Emodina/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Flavonoides/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
7.
Materials (Basel) ; 11(11)2018 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-30373122

RESUMO

Synaptic devices with bipolar analog resistive switching behavior are the building blocks for memristor-based neuromorphic computing. In this work, a fully complementary metal-oxide semiconductor (CMOS)-compatible, forming-free, and non-filamentary memristive device (Pd/Al2O3/TaOx/Ta) with bipolar analog switching behavior is reported as an artificial synapse for neuromorphic computing. Synaptic functions, including long-term potentiation/depression, paired-pulse facilitation (PPF), and spike-timing-dependent plasticity (STDP), are implemented based on this device; the switching energy is around 50 pJ per spike. Furthermore, for applications in artificial neural networks (ANN), determined target conductance states with little deviation (<1%) can be obtained with random initial states. However, the device shows non-linear conductance change characteristics, and a nearly linear conductance change behavior is obtained by optimizing the training scheme. Based on these results, the device is a promising emulator for biology synapses, which could be of great benefit to memristor-based neuromorphic computing.

8.
Immunopharmacol Immunotoxicol ; 40(5): 430-436, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30366509

RESUMO

OBJECTIVE: To explore the effect of suppressive oligodeoxynucleotide-induced dendritic cells (S-DCs) in the osteoarthritis (OA) therapy. METHODS: S-DCs were prepared from splenic CD11c + cells by in vitro culture with suppressive oligodeoxynucleotide. The function and phenotypes of S-DCs were measured by ELISA and flow cytometry. The innate immune signaling pathways were detected by western blotting in the non-treated DCs and S-DCs upon stimulation. In vivo, we employed an iodoacetate-induced OA mice model. S-DCs were transferred by intravenous route. The weight bearing of mice was evaluated and pro-inflammatory factors in OA joint were measured by real-time PCR. Treg cell ratio and CD4 + IL10+ cells in spleen were detected by flow cytometry at day 5 post OA induction. RESULTS: The S-DCs showed less inflammatory phenotypes upon stimulation. The expression of pro-inflammatory cytokines and mature makers in the S-DCs were blunt, due to the impaired innate immune signal transduction. In an iodoacetate-induced OA model, transfer of S-DCs significantly controlled the process of OA. Restricted inflammatory responses were observed in the joint of S-DC recipients. Moreover, after S-DC transfer, Tregs and CD4 + IL10+ cells were mounted in the spleen. CONCLUSION: Transfer of suppressive oligodeoxynucleotides-induced autologous DCs may represent a potential agent to control the aggravation of OA in patients.


Assuntos
Transferência Adotiva/métodos , Células Dendríticas/imunologia , Oligodesoxirribonucleotídeos/farmacologia , Osteoartrite/terapia , Baço/imunologia , Animais , Células Dendríticas/citologia , Células Dendríticas/efeitos dos fármacos , Modelos Animais de Doenças , Imunidade Inata/efeitos dos fármacos , Interleucina-10/imunologia , Camundongos Endogâmicos C57BL , Osteoartrite/imunologia , Baço/citologia , Baço/efeitos dos fármacos , Linfócitos T Reguladores/imunologia
9.
Restor Neurol Neurosci ; 36(5): 605-620, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30040767

RESUMO

BACKGROUND: Transcranial direct current stimulation (tDCS) on primary motor cortex (M1) provides a new way to relieve postoperative pain. Previous studies only found postoperative analgesia dosage significantly reduced in tDCS group while the patient-controlled analgesia (PCA) was applied. However, there lacks the study about the effect of M1-tDCS on pain intensity and brain activity while the analgesia dosage is the same for both groups. OBJECTIVE: To investigate whether M1-tDCS can (1) reduce pain intensity and (2) change spontaneous electroencephalography (EEG) oscillations in prefrontal cortex, in patients with postoperative pain, after taking the constant dosage of analgesics. METHODS: A prospective, single-blind, randomized, sham-controlled study was conducted. 32 patients with postoperative pain after lumbar spine surgery were recruited. All patients received same dosage of dezocine before intervention. In the morning of the first day after surgery and before dezocine injection, a single 20-minute session of anodal M1-tDCS was applied to 'tDCS' group while sham stimulation to 'sham' group. Numeric rating scale (NRS) and resting-state EEG with eyes-closed were measured and analyzed. EEG spectral powers were analyzed using repeated measures analysis of variance (ANOVA). Correlation analysis was conducted between the change of NRS and the change of spectral power. RESULTS: The NRS in "tDCS" group significantly decreased (p < 0.01) while not in "sham" group after intervention. Only spectral power within alpha2 band (10-13 Hz) in Fp1 and beta1 band (13-20 Hz) in Fp1 showed significant Time×Intervention interaction effect. These changes of the spectral power also showed significant correlation with the change of NRS. CONCLUSIONS: The postoperative pain intensity in patients receiving surgery could reduce after a single session of anodal M1-tDCS compared to sham M1-tDCS. The effect to the top-down dimension of postoperative pain might account for the analgesic effect of M1-tDCS, which reflecting slow oscillations in left prefrontal EEG.


Assuntos
Vértebras Lombares/cirurgia , Córtex Motor/fisiopatologia , Dor Pós-Operatória/fisiopatologia , Dor Pós-Operatória/terapia , Estimulação Transcraniana por Corrente Contínua , Adolescente , Adulto , Idoso , Analgésicos/uso terapêutico , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Descanso , Método Simples-Cego , Estimulação Transcraniana por Corrente Contínua/efeitos adversos , Estimulação Transcraniana por Corrente Contínua/métodos , Resultado do Tratamento , Adulto Jovem
10.
Int Immunopharmacol ; 58: 154-159, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29587204

RESUMO

Aging is associated with the development of osteoporosis, in which cellular senescence in osteoblasts plays a key role. Leukotriene D4 (LTD4), an important cysteinyl leukotriene (cysLT), is a powerful pro-inflammatory mediator formed from arachidonic acid. However, little information regarding the effects of LTD4 on the pathogenesis of osteoporosis has been reported before. In the present study, we defined the physiological roles of LTD4 in cellular senescence in osteoblasts. Our results indicate that LTD4 treatment decreased the expression of SIRT1 in a dose-dependent manner in MC3T3-E1 osteoblastic cells. Additionally, LTD4 significantly increased the expression of p53, p21 and plasminogen activator inhibitor-1 (PAI-1). LTD4 was also found to elevate the activity of ß-galactosidase (SA-ß-Gal) but to prevent BrdU incorporation. Our results indicate that cysteinyl leukotriene receptor 1 (cysLT1R) could be detected in MC3T3-E1 osteoblastic cells at both the mRNA and protein levels. However, cysLT2R was not expressed in these cells. Interestingly, we found that knockdown of cysLT1R or use of the selective cysLT1R antagonist montelukast abolished the LTD4-induced reduction in SIRT1 and increase in p53, p21, and PAI-1. Notably, knockdown of cysLT1R by transfection with cysLT1R siRNA or treatment with montelukast attenuated the LTD4-induced increase in SA-ß-Gal activity. Our study shows for the first time that LTD4 has a significant impact on cellular senescence in osteoblasts.


Assuntos
Leucotrieno D4/metabolismo , Osteoblastos/fisiologia , Osteoporose/imunologia , Acetatos/farmacologia , Animais , Linhagem Celular , Senescência Celular , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Humanos , Camundongos , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Quinolinas/farmacologia , RNA Interferente Pequeno/genética , Receptores de Leucotrienos/genética , Receptores de Leucotrienos/metabolismo , Sirtuína 1/metabolismo , Proteína Supressora de Tumor p53/metabolismo , beta-Galactosidase/metabolismo
11.
Biochem Biophys Res Commun ; 495(1): 995-1001, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29032198

RESUMO

Long-term exposure to overloaded mechanical environment induces bone fatigue damage symptoms and osteoblast damages. Montelukast is a selective cysteinyl leukot-riene receptor 1 (cysLT1R) antagonist, which has been used for the treatment of bronchial asthma in clinics. In the current study, we have identified a novel pharmacological role of montelukast by finding that it has protective properties against overload damage in osteoblastic MC3T3-E1 cells. Firstly, our results show that CysLT1R is expressed in MC3T3-E1 cells. Mechanical tensile strain of 5000-7000 µÎµ resulted in a significant upregulation of CysLT1R in osteoblastic MC3T3-E1 cells in an intensity dependent manner. Secondly, MTT assay indicates that loading with 5000 µÎµ mechanical strain inhibited cell proliferation, which was suppressed by montelukast treatment. Furthermore, montelukast promotes cell differentiation by increasing the expression of ALP and RUNX2. Alizarin Red S staining assay showed that montelukast abolished the inhibitory effects of overload mechanics on osteoblast mineralization. Mechanistically, the effect of montelukast on osteoblastic differentiation acted by activating the extracellular regulated protein kinases (ERK) pathway. The obtained results suggested that montelukast promotes proliferation and differentiation in osteoblasts exposed to overload mechanics.


Assuntos
Acetatos/administração & dosagem , Diferenciação Celular/fisiologia , Antagonistas de Leucotrienos/administração & dosagem , Mecanotransdução Celular/fisiologia , Osteoblastos/fisiologia , Osteogênese/efeitos dos fármacos , Quinolinas/administração & dosagem , Receptores de Leucotrienos/metabolismo , Células 3T3 , Animais , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Camundongos , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteogênese/fisiologia , Receptores de Leucotrienos/efeitos dos fármacos , Estresse Mecânico
12.
Int Immunopharmacol ; 55: 193-197, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29268191

RESUMO

Bacterial products such as LPS are critical factors responsible for bone destruction. MMP-13, a member of the matrix metalloproteinase family, plays a critical role in the proteolytic degradation of extracellular matrix components, which includes collagen fibrils in the bone matrix. Montelukast is a selective cysteinyl leukotrienes receptor 1 (cysLT1R) antagonist used clinically for the treatment of asthma, as it reduces eosinophilic inflammation in airways. This study aims to explore the role of montelukast in regulating MMP-13 expression induced by LPS in osteoblasts. Our results indicate that LPS stimulated cysLT1R expression in mouse MC3T3-E1 osteoblasts in a dose- and time-dependent manner. Notably, LPS-induced up-regulation of MMP-13 was ameliorated by treatment with montelukast in a dose-dependent manner. Furthermore, treatment with montelukast stimulated the expression of SOCS3, an inhibitor of MMP-13. Silencing of SOCS3 abolished the inhibitory effects of montelukast on MMP-13 expression. Mechanistically, we found that montelukast suppressed LPS-induced nuclear translocation of NF-κB p65 as well as NF-κB transcriptional activity by inhibiting the phosphorylation and degradation of IκBα. These data suggest that montelukast can modulate inflammatory events in bone diseases.


Assuntos
Doenças Ósseas/tratamento farmacológico , Metaloproteinase 13 da Matriz/metabolismo , Osteoblastos/efeitos dos fármacos , Acetatos , Animais , Antiasmáticos , Linhagem Celular , Regulação da Expressão Gênica , Humanos , Lipopolissacarídeos/metabolismo , Metaloproteinase 13 da Matriz/genética , Camundongos , NF-kappa B/metabolismo , Osteoblastos/fisiologia , Quinolinas , RNA Interferente Pequeno/genética , Receptores de Leucotrienos/metabolismo , Proteína 3 Supressora da Sinalização de Citocinas/genética , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo
13.
Stem Cells Int ; 2017: 7371615, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28484496

RESUMO

Background. The functions of insulin in mesenchymal stem cells (MSC) remain poorly understood. Methods. MSC from human umbilical cord matrix (UCM) cultured in serum-free media (SFM) with or without insulin were subjected to various molecular biological analyses to determine their proliferation and growth states, expression levels of Akt-cyclin D1 signaling molecules, and in vitro differentiation capacities. Results. Insulin accelerated the G1-S cell cycle progression of UCM-MSC and significantly stimulated their proliferation and growth in SFM. The pro-proliferative action of insulin was associated with augmented cyclin D1 and phosphorylated Akt expression levels. Akt inactivation remarkably abrogated insulin-induced increases in cyclin D1 expression and cell proliferation, indicating that insulin enhances the proliferation of UCM-MSC via acceleration of the G1-S transition mediated by the Akt-cyclin D1 pathway. Additionally, the UCM-MSC propagated in SFM supplemented with insulin exhibited similar specific surface antigen profiles and differentiation capacities as those generated in conventional media containing fetal bovine serum. Conclusions. These findings suggest that insulin acts solely to promote UCM-MSC proliferation without affecting their immunophenotype and differentiation potentials and thus have important implications for utilizing insulin to expand clinical-grade MSC in vitro.

14.
Stem Cells Int ; 2016: 9458396, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27994625

RESUMO

We evaluated the efficacy of platelet-rich plasma (PRP) in combination with allogeneic bone marrow mesenchymal stem cells (BMSCs) for the treatment of osteoporotic bone defects in an ovariectomized rat model. By day 42 after injury, in vivo microcomputed tomography (micro-CT) imaging revealed that bone defects of control rats and ovariectomized rats treated with PRP and BMSCs were completely repaired, whereas those of ovariectomized rats treated with PRP or BMSCs alone exhibited slower healing. Histological data were consistent with these results. We also assessed changes to bone trabeculae in the proximal tibial growth plate. In ovariectomized rats treated with PRP or with a combination of PRP and BMSCs, the trabecular connectivity densities (Conn.D), bone volume ratios (BV/TV), and numbers (Tb.N) in the defect areas increased significantly from day 7 to day 42. These results indicate that PRP treatment enhances bone microarchitecture in osteoporosis. Moreover, expression levels of osteogenesis-specific marker genes including RUNX2, OSX, and OPN were significantly upregulated in rats treated with PRP and BMSCs compared to those of other groups. Thus, we conclude that treatment with PRP combined with BMSCs significantly promotes healing of osteoporotic bone defects. This study provides an alternative strategy for the treatment of osteoporotic bone loss.

15.
Biomed Res Int ; 2016: 4013487, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27830143

RESUMO

MicroRNA-146a participates in spinal cord injury (SCI) recovery. Until recently, how miRNA-146a participates in SCI remained unclear. In this study, we tried to explore the roles of miRNA-146a in the recovery of SCI using a rat model. The expression of the probable target genes of miRNA-146a (including IRAK1 and TARF6) as well as proinflammation cytokines were measured until 7 days after surgery in the three groups (sham group, SCI group, and miRNA-146a antagomir injection group). Also, the animals' motivations were estimated using Basso Beattie Bresnahan (BBB) during the whole experiment. A luciferase assay was performed to demonstrate that miRNA-146a could directly target the mRNAs of IRAK1 and TRAF6. Our experiments indicate that miRNA-146a inhibits proinflammatory cytokine secretion by suppressing IRAK1 and TRAF6 expression in the SCI model. In contrast, miRNA-146a may be upregulated by inflammatory mediators via the IRAK1/TRAF6 pathway in the spinal cord. As a negative feedback element, miRNA-146a could make sure that the expression of IRAK1- and TRAF6-mediated genes was under tight control. Thus, miRNA-146a may serve as a novel therapeutic target for SCI interventions.


Assuntos
Regulação da Expressão Gênica , Quinases Associadas a Receptores de Interleucina-1/metabolismo , MicroRNAs/metabolismo , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/fisiopatologia , Fator 6 Associado a Receptor de TNF/metabolismo , Animais , Feminino , Ratos , Ratos Wistar , Vértebras Torácicas/lesões
16.
Oncotarget ; 7(21): 31429-39, 2016 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-27119226

RESUMO

Osteoporosis is a common human complex disease. It is mainly characterized by low bone mineral density (BMD) and low-trauma osteoporotic fractures (OF). Until now, a large proportion of heritability has yet to be explained. The existing large-scale genome-wide association studies (GWAS) provide strong support for the investigation of osteoporosis mechanisms using pathway analysis. Recent findings showed that different risk pathways may be involved in BMD in different tissues. Here, we conducted multiple pathway analyses of a large-scale lumbar spine BMD GWAS dataset (2,468,080 SNPs and 31,800 samples) using two published gene-based analysis software including ProxyGeneLD and the PLINK. Using BMD genes from ProxyGeneLD, we identified 51 significant KEGG pathways with adjusted P<0.01. Using BMD genes from PLINK, we identified 38 significant KEGG pathways with adjusted P<0.01. Interestingly, 33 pathways are shared in both methods. In summary, we not only identified the known risk pathway such as Wnt signaling, in which the top GWAS variants are significantly enriched, but also highlight some new risk pathways. Interestingly, evidence from further supports the involvement of these pathways in MBD.


Assuntos
Densidade Óssea/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Vértebras Lombares , Osteoporose/genética , Humanos , Desequilíbrio de Ligação , Osteoporose/diagnóstico , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Transdução de Sinais/genética , Via de Sinalização Wnt/genética
17.
Microb Pathog ; 90: 34-40, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26596708

RESUMO

Infections of pathogenic bacteria are very common in acquired immunodeficiency syndrome (AIDS) patients. However, the biological effects of HIV-1 Tat on bacteria are incompletely understood. In this study, HIV-1 Tat was expressed in Escherichia coli and Pseudomonas aeruginosa (PA01) to investigate its biological effects on bacteria. Bacterial cells expressing either HIV-1 Tat1-86 (Tat1-86) or HIV-1 Tat1-72 (Tat1-72) grow significantly faster than those with either only an empty vector or an unrelated control (GFP or Rluc). Supplementation of purified HIV-1 Tat1-86 or Tat1-101 protein into bacterial culture medium stimulated the growth of both E. coli and PA01. The expression profile of certain cell division-associated genes, such as those in the division cell wall (dcw) operon (ftsA, ftsQ, ftsW and ftsZ), yafO and zipA, was altered in HIV-1 Tat1-86 expressing E. coli BL21(DE3). Furthermore, the expression of firefly luciferase (Fluc) reporter gene, when engineered for control by the dcw promoter and terminator, was enhanced by HIV-1 Tat in E. coli, confirming that HIV-1 Tat transcriptionally regulates the expression of the dcw operon. The finding that HIV-1 Tat stimulates bacterial growth whether it is produced intracellularly or applied extracellularly may have relevance for HIV patients who are highly susceptible to opportunistic bacterial infections. Contents category: Viruses -Retroviruses. The GenBank accession number for the sequence of HIV-1 Tat1-86 is AF324439.1.


Assuntos
Parede Celular/genética , Escherichia coli/citologia , HIV-1/fisiologia , Óperon , Pseudomonas aeruginosa/citologia , Produtos do Gene tat do Vírus da Imunodeficiência Humana/fisiologia , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Parede Celular/metabolismo , Retrovirus Endógenos/genética , Escherichia coli/genética , Escherichia coli/metabolismo , HIV-1/genética , Fragmentos de Peptídeos/farmacologia , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Transcrição Genética , Ativação Transcricional , Produtos do Gene tat do Vírus da Imunodeficiência Humana/biossíntese , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética , Produtos do Gene tat do Vírus da Imunodeficiência Humana/farmacologia
18.
Mol Med Rep ; 12(2): 1717-26, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25891179

RESUMO

The objective of the present study was to assess the effectiveness of combined salmon calcitonin (sCT) and aspirin [acetylsalicylic acid (ASA)] treatment in an ovariectomized (OVX) rat model of postmenopausal osteoporosis. Following 12 weeks of treatment, therapeutic efficacy was assessed by evaluating changes in the biochemical and biophysical properties of bone (n=8 rats per group). Serological markers of bone metabolism were measured by ELISA; bone mineral densities (BMD) by dual energy X-ray absorptiometry; bone biomechanics of the femur and lumbar vertebrae by three-point stress test; trabecular bone morphology of lumbar vertebrae by hematoxylin and eosin staining; messenger RNA expression levels of osteoprotegerin (OPG) and receptor activator of nuclear factor κB ligand (RANKL) in bone marrow cells by reverse transcription-quantitative polymerase chain reaction and OPG and RANKL protein expression levels in the proximal tibia were analyzed by immunohistochemistry. Compared with treatment by sCT or ASA alone, combined treatment (sCT+ASA) increased BMD, improved femur bone strength, normalized trabecular network architecture and morphology, and increased mRNA and protein expression of OPG, while reducing the expression of RANKL. Collectively, these results demonstrated that combined treatment (sCT+ASA) of osteoporotic symptoms in OVX rats was more effective than treatment with sCT or ASA alone. Furthermore, these two drugs appeared to alter the expression of two distinct factors in the OPG/RANKL/RANK system, suggesting that their effects may be synergistic. Since sCT and ASA are currently approved for use in humans, the results of the present study suggest that the safety and efficacy of sCT+ASA combined therapy for post-menopausal osteoporosis should be assessed in clinical trials.


Assuntos
Aspirina/uso terapêutico , Calcitonina/uso terapêutico , Osteoporose/tratamento farmacológico , Animais , Biomarcadores/metabolismo , Densidade Óssea , Feminino , Fêmur/patologia , Fêmur/fisiologia , Imuno-Histoquímica , Vértebras Lombares/patologia , Vértebras Lombares/fisiologia , Osteoporose/patologia , Osteoporose/veterinária , Osteoprotegerina/genética , Osteoprotegerina/metabolismo , Ovariectomia , Ligante RANK/genética , Ligante RANK/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Tíbia/metabolismo
19.
PLoS One ; 9(10): e107885, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25271765

RESUMO

The application of the luxCDABE operon of the bioluminescent bacterium Photorhabdus luminescens as a reporter has been published for bacteria, yeast and mammalian cells. We report here the optimization of fused luxAB (the bacterial luciferase heterodimeric enzyme) expression, quantum yield and its application as a reporter gene in plant protoplasts. The fused luxAB gene was mutated by error prone PCR or chemical mutagenesis and screened for enhanced luciferase activity utilizing decanal as substrate. Positive luxAB mutants with superior quantum yield were subsequently shuffled by DNase I digestion and PCR assembly for generation of recombinants with additional increases in luciferase activity in bacteria. The coding sequence of the best recombinant, called eluxAB, was then optimized further to conform to Arabidopsis (Arabidopsis thaliana) codon usage. A plant expression vector of the final, optimized eluxAB gene (opt-eluxAB) was constructed and transformed into protoplasts of Arabidopsis and maize (Zea mays). Luciferase activity was dramatically increased for opt-eluxAB compared to the original luxAB in Arabidopsis and maize cells. The opt-eluxAB driven by two copies of the 35S promoter expresses significantly higher than that driven by a single copy. These results indicate that the eluxAB gene can be used as a reporter in plant protoplasts. To our knowledge, this is the first report to engineer the bacterium Photorhabdus luminescens luciferase luxAB as a reporter by directed evolution which paved the way for further improving the luxAB reporter in the future.


Assuntos
Expressão Gênica , Genes Reporter , Luciferases Bacterianas/genética , Plantas/metabolismo , Protoplastos/metabolismo , Códon , Embaralhamento de DNA , Estabilidade Enzimática , Ordem dos Genes , Genes de Plantas , Concentração de Íons de Hidrogênio , Luciferases Bacterianas/química , Modelos Moleculares , Dados de Sequência Molecular , Mutação , Plantas/genética , Plasmídeos/genética , Conformação Proteica , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo , Temperatura Ambiente , Zea mays/genética , Zea mays/metabolismo
20.
Asian Pac J Trop Med ; 7(10): 801-5, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25129464

RESUMO

OBJECTIVES: To study the effect of aspirin on healing process of osteoporotic fracture (OPF) in rats. METHODS: A total of 50 female Wistar rats aged 3 months were randomly divided into observation group and control group, castration method was adopted to establish the osteoporosis (OP) model. After artificial preparing fractures on the midpoint of left femur, fixing gram needle intramedullary, OPF modeling was complete. Aspirin lavage of 33 mg once a day was adopted in observation group after modeling, same amount of normal saline was used in the control as placebo. From each group, selected 5 rats at the 2nd, 4th, 8th and 12th week after modeling to measure the bone mineral density (BMD) and histological examination of the fracture callus, radiology observation was conducted at the 8th and 12th week. Left femur biomechanical measurement was taken at the 12th week. RESULTS: BMD values of observation group at each time point were significantly higher than that of the control group after modeling (P<0.05); Histological observation showed that at the 8th week, the endochondral ossification process of observation group was faster than that of observation group, with fuzzy fracture line in observation group and clear fracture line in observation group; at the 12th week, fracture line disappeared in observation group, fracture line of the control group was fuzzy at the same time; three-point bending load of the left femur in observation group rats was significantly higher than that of control group after 12 weeks (P<0.05). CONCLUSIONS: Aspirin can accelerate the healing of new callus in OPF rats, increase bone density and biomechanics strength, and promote fracture healing of osteoporotic rats.

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