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1.
Sensors (Basel) ; 20(6)2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32197503

RESUMO

For total knee replacement (TKR) patients, rehabilitation after the surgery is key toregaining mobility. This study proposes a sensor-based system for effectively monitoringrehabilitation progress after TKR. The system comprises a hardware module consisting of thetriaxial accelerometer and gyroscope, a microcontroller, and a Bluetooth module, and a softwareapp for monitoring the motion of the knee joint. Three indices, namely the number of swings, themaximum knee flexion angle, and the duration of practice each time, were used as metrics tomeasure the knee rehabilitation progress. The proposed sensor device has advantages such asusability without spatiotemporal constraints and accuracy in monitoring the rehabilitation progress.The performance of the proposed system was compared with the measured range of motion of theCybex isokinetic dynamometer (or Cybex) professional rehabilitation equipment, and the resultsrevealed that the average absolute errors of the measured angles were between 1.65° and 3.27° forthe TKR subjects, depending on the swing speed. Experimental results verified that the proposedsystem is effective and comparable with the professional equipment.

2.
J Asian Nat Prod Res ; : 1-10, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31791147

RESUMO

Various bioactive polyketides have been found in Aloe barbadensis. However, the polyketide synthases (PKSs), which participate in biosynthesis of polyketides in A. barbadensis remain unknown. In this study, two type III PKSs (AbPKS1 and AbPKS2) were identified from A. barbadensis. AbPKS1 and AbPKS2 were able to utilize malonyl-CoA to yield heptaketides (TW93a and aloesone) and octaketides (SEK4 and SEK4b), respectively. AbPKS1 also exhibited catalytic promiscuity in recognizing CoA thioesters of aromatics to produce unusual polyketides. What Is more, a whole cell biocatalysis system with the capability of producing 26.4 mg/L of SEK4/SEK4b and 2.1 mg/L of aloesone was successfully established.

3.
Int J Oncol ; 54(6): 1907-1920, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31081062

RESUMO

The p53 protein is a tumour suppressor and transcription factor that regulates the expression of target genes involved in numerous stress responses systems. In this study, we designed a screening strategy using DNA damage­induced mouse and human transcriptome data to identify novel downstream targets of p53. Our method selected genes with an induced expression in multiple organs of X­ray­irradiated p53 wild­type mice. The expression of inka box actin regulator 2 gene, known as Inka2, was upregulated in 12 organs when p53 expression was induced. Similarly, INKA2 was induced in a p53­dependent manner at both the mRNA and protein level in human cells treated with adriamycin. Reporter assays confirmed that p53 directly regulated INKA2 through an intronic binding site. The overexpression of INKA2 produced a slight decrease in cancer cell growth in the colony formation assay. Moreover, the analysis of The Cancer Genome Atlas (TCGA) data revealed a decreased INKA2 expression in tumour samples carrying p53 mutations compared with p53 wild­type samples. In addition, significantly higher levels of DNA methylation were observed in the INKA2 promoter in tumour samples, concordant with the reduced INKA2 expression in tumour tissues. These results demonstrate the potential of INKA2 as a cancer cell growth inhibitor. Furthermore, INKA2 protein interacts with the serine/threonine­protein kinase, p21 (RAC1) activated kinase (PAK)4, which phosphorylates ß­catenin to prevent ubiquitin­proteasomal degradation. As ß­catenin was downregulated in a stable INKA2­expressing cell line, the findings of this study suggest that INKA2 is a novel, direct downstream target of p53 that potentially decreases cell growth by inhibiting the PAK4­ß­catenin pathway.


Assuntos
Perfilação da Expressão Gênica/métodos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias/genética , Proteína Supressora de Tumor p53/metabolismo , Quinases Ativadas por p21/metabolismo , Animais , Linhagem Celular Tumoral , Metilação de DNA , Doxorrubicina/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos da radiação , Células HCT116 , Humanos , Camundongos , Mutação , Neoplasias/metabolismo , Fosforilação , Regiões Promotoras Genéticas , Análise de Sequência de RNA/métodos , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , beta Catenina/metabolismo
4.
J Phys Chem A ; 123(13): 2789-2795, 2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30865457

RESUMO

Blue-light-emitting semiconductors based on polyfluorenes often exhibit an undesired green emission band. In this report, three well-defined oligofluorenes corresponding to three types of "defects" attributed to aggregation, keto formation, and chain entanglement, respectively, are systemically investigated to unveil the origins of the green emission band in fluorene-based materials. First, the optical properties of defect molecules in different states are studied. The defect associated with aggregation is absent in dilute solutions and in films doped at 0.01 wt % with poly(methyl methacrylate). Second, the dependence of the emission spectra on the solvent was monitored to compare the effects of the "keto-" and "chain-entanglement defect" molecules. The green emission of keto defects exhibited a strong dependence on solvent polarity, whereas this cannot be observed in case of chain-entanglement defect. Third, energy transfer between poly[4-(octyloxy)-9,9-diphenylfluoren-2,7-diyl]- co-[5-(octyloxy)-9,9-diphenyl-fluoren-2,7-diyl] and the keto or chain-entanglement defect molecules is illustrated. Compared to those of the chain-entanglement defect, the spectra of the keto defect molecule (1:10-3) show signs of defect emission at lower proportions. These investigations not only provide insight into the photophysics of oligofluorenes but also supply a new strategy to explore defects in semiconductor polymers, which will aid in the development of effective approaches to obtain stable, pure blue organic light-emitting diodes based on polyfluorenes.

5.
Acta Pharmacol Sin ; 39(4): 633-641, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29323335

RESUMO

Glucocorticoid (GC)-induced osteoporosis (GIO) is characterized by impaired bone formation, which can be alleviated by tanshinol, an aqueous polyphenol isolated from Salvia miltiorrhiza Bunge. In this study we investigated the molecular mechanisms underlying GC-induced modulation of osteogenesis as well as the possibility of using tanshinol to interfere with GIO. Female SD rats aged 4 months were orally administered distilled water (Con), prednisone (GC, 5 mg·kg-1·d-1), GC plus tanshinol (Tan, 16 mg·kg-1·d-1) or GC plus resveratrol (Res, 5 mg·kg-1·d-1) for 14 weeks. After the rats were sacrificed, samples of bone tissues were collected. The changes in bone formation were assessed using Micro-CT, histomorphometry, and biomechanical assays. Expression of Kruppel-like factor 15 (KLF15), peroxisome proliferator-activated receptor γ 2 (PPARγ 2) and other signaling proteins in skeletal tissue was measured with Western blotting and quantitative RT-PCR. GC treatment markedly increased the expression of KLF15, PPARγ2, C/EBPα and aP2, which were related to adipogenesis, upregulated FoxO3a pathway proteins (FoxO3a and Gadd45a), and suppressed the canonical Wnt signaling (ß-catenin and Axin2), which was required for osteogenesis. Thus, GC significantly decreased bone mass and bone quality. Co-treatment with Tan or Res effectively counteracted GC-impaired bone formation, suppressed GC-induced adipogenesis, and restored abnormal expression of the signaling molecules in GIO rats. We conclude that tanshinol counteracts GC-decreased bone formation by inhibiting marrow adiposity via the KLF15/PPARγ2/FoxO3a/Wnt pathway.


Assuntos
Adipogenia/efeitos dos fármacos , Ácidos Cafeicos/uso terapêutico , Osteogênese/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Via de Sinalização Wnt/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Medula Óssea/metabolismo , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Regulação para Baixo , Proteínas de Ligação a Ácido Graxo/genética , Feminino , Proteína Forkhead Box O3/genética , Fatores de Transcrição Kruppel-Like/genética , PPAR gama/genética , Prednisona/administração & dosagem , Prednisona/farmacologia , Ratos Sprague-Dawley , Resveratrol , Estilbenos/administração & dosagem , Estilbenos/farmacologia , Regulação para Cima , Via de Sinalização Wnt/genética
6.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 33(3): 244-247, 2017 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-29931940

RESUMO

OBJECTIVE: To make risk stratification of aged patients with coronary artery disease by deceleration capacity of rate (DC) and heart rate deceleration runs (DRs) and to investigate the value of the two detection technologies in warning sudden cardiac death. METHODS: Two hundrend and eighteen patients diagnosed with coronary artery disease (CAD) by coronary angiography (CAG) were selected as observa-tion group:including 55 patients with latent coronary artery disease (LCHD), 56 patients with acute myocardial infarction (AMI), 53 patients with angina pectoris (AP), 54 patients with ischemic heart failure. Fifty-five healthy controls in our hospital were selected at the same time (control group). All patients were detected by 24-hour dynamic electrocardiogram while values of DC and DRs were automatically analyzed and calculated by software. RESULTS: The values of DC and DRs descended significantly in all CHD groups (AMI group, AP group, Ischemic Heart Failure group, LCHD group) and the difference was statistically significant (P < 0.01) compared with normal group; DC and DRs indicated the risk classification of each CAD subgroup was obviously higher than those in normal group and the difference was statistically significant(P < 0.01); CAG showed that the more coronary lesions, the larger the rage, prompt the heavier the illness, which was consistent with the risk classification of each CHD subgroup indicated by DC and DRs. CONCLUSIONS: DC and DRs can be used to analyze the function of vagus nerve, it also can be used to make risk classification of patients with CHD, and it has a higher value of pre-warning for high-risk groups. DC and DRs can be used as sensitive indexes in warning sudden cardiac death of patients with CHD.


Assuntos
Doença da Artéria Coronariana/complicações , Morte Súbita Cardíaca , Coração/fisiopatologia , Infarto do Miocárdio/complicações , Estudos de Casos e Controles , Angiografia Coronária , Humanos , Medição de Risco
7.
Phys Chem Chem Phys ; 18(14): 9412-8, 2016 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-26979556

RESUMO

The charge trapping properties of the blend of polystyrene (PS) and a sterically hindered organic semiconductor SFDBAO (spiro[fluorene-9,7-dibenzo[c,h]acridin-5-one]) are investigated by electrostatic and Kelvin probe force microscopy (EFM and KPFM). EFM signals of trapped charge spots injected with controllable tip biases, which are recorded with different dissipation times t, the percent of SFDBAO in blends, and the scanning tip bias, have been measured. By the quantitative analysis, the excellent trapped charge density of PS/SFDBAO blend films for the holes (∼×10(-5) C m(-2)) is much higher than that of the SFDBAO film (∼×10(-6) C m(-2)) and the PS film (∼×10(-7) C m(-2)). However, the trapped charge density of electrons (∼×10(-7) C m(-2)) has the same order magnitude for SFDBAO, PS and the blend films. The results indicate that the blend of PS and SFDBAO enhances the high-density storage and retention abilities of the holes to a larger extent, but the endurance improvement of the electrons is not that obvious. By the KPFM measurement, we further verify the different diffusion rates of the trapped holes and electrons in the PS/SFDBAO blend films, and discuss the possible physical mechanism. The qualitative and quantitative determination of charge trapping properties in this work can be very useful for the characterization of PS/SFDBAO based charge trapping memory devices.

8.
Zhongguo Zhong Yao Za Zhi ; 41(12): 2175-2182, 2016 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-28901056

RESUMO

Acylation conducted by acyltransferase is a ubiquitous process in structure modification of secondary metabolites. It plays an important role in the structural diversity of natural products and contributes significantly to their improved stabilities, increased solubilities, and enhanced bioavailabilities. BAHD acyltransferase family is a typical kind of acyltransferase original from plants, which involved in the biosynthesis of various bioactive acylated natural products. In order to provide references for future investigations of BAHD acyltransferase family, research progresses on basic properties, three-dimensional structures, catalytic mechanisms, enzymatic functional identifications and phylogenetic analyses of BAHD family from plants is summarized in this paper.


Assuntos
Aciltransferases , Plantas/enzimologia , Filogenia , Metabolismo Secundário
9.
Org Lett ; 18(2): 172-5, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26695881

RESUMO

[4]Cyclo-9,9-dipropyl-2,7-fluorene ([4]CF) with the strain energy of 79.8 kcal/mol is synthesized in high quantum yield. Impressively, hoop-shaped [4]CF exhibits a green fluorescence emission around 512 nm offering a new explanation for the green band (g-band) in polyfluorenes. The solution-processed [4]CF-based organic light emitting diode (OLED) has also been fabricated with the a stronger green band emission. Strained semiconductors offer a promising approach to fabricating multifunctional optoelectronic materials in organic electronics and biomedicine.

10.
Development ; 142(9): 1705-16, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25922527

RESUMO

Macroautophagic degradation of sperm-inherited organelles prevents paternal mitochondrial DNA transmission in C. elegans. The recruitment of autophagy markers around sperm mitochondria has also been observed in mouse and fly embryos but their role in degradation is debated. Both worm Atg8 ubiquitin-like proteins, LGG-1/GABARAP and LGG-2/LC3, are recruited around sperm organelles after fertilization. Whereas LGG-1 depletion affects autophagosome function, stabilizes the substrates and is lethal, we demonstrate that LGG-2 is dispensable for autophagosome formation but participates in their microtubule-dependent transport toward the pericentrosomal area prior to acidification. In the absence of LGG-2, autophagosomes and their substrates remain clustered at the cell cortex, away from the centrosomes and their associated lysosomes. Thus, the clearance of sperm organelles is delayed and their segregation between blastomeres prevented. This allowed us to reveal a role of the RAB-5/RAB-7 GTPases in autophagosome formation. In conclusion, the major contribution of LGG-2 in sperm-inherited organelle clearance resides in its capacity to mediate the retrograde transport of autophagosomes rather than their fusion with acidic compartments: a potential key function of LC3 in controlling the fate of sperm mitochondria in other species.


Assuntos
Autofagia/fisiologia , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiologia , Proteínas Associadas aos Microtúbulos/metabolismo , Organelas/metabolismo , Espermatozoides/citologia , Animais , Transporte Biológico , Herança Extracromossômica/fisiologia , Imunofluorescência , Masculino , Microscopia Eletrônica de Transmissão , Interferência de RNA
11.
Phys Chem Chem Phys ; 17(7): 4919-25, 2015 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-25559269

RESUMO

Defect engineering and the non-covalent interaction strategy allow for dramatically tuning the optoelectronic features of graphene. Herein, we theoretically investigated the intrinsic mechanism of non-covalent interactions between pentagon-octagon-pentagon (5-8-5) defect graphene (DG) and absorbed molecules, tetrathiafulvalene (TTF), perfluoronaphthalene (FNa), tetracyanoquinodimethane (TCNQ) and 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ), through geometry, distance, interaction energy, Mulliken charge distribution, terahertz frequency vibration, visualization of the interactions, charge density difference, electronic transition behaviour, band structure and density of state. All the calculations were performed using density functional theory including a dispersion correction (DFT-D). The calculated results indicate that the cyano- (CN) group (electron withdraw group) in TCNQ and F4TCNQ, rather than the F group, gain the electron from DG effectively and exhibit much stronger interactions via wavefunction overlap with DG, leading to a short non-covalent interaction distance, a large interaction energy and a red-shift of out-of-plane terahertz frequency vibration, changing the bands near the Fermi level and enhancing the infrared (IR) light absorption significantly. The enhancement of such IR absorbance offering a broader absorption (from 300 to 1200 nm) will benefit light harvesting in potential applications of solar energy conversion.

12.
Org Lett ; 16(6): 1748-51, 2014 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-24611841

RESUMO

A series of fluorene-based grid molecules (so-called Grid fluorenes) have been synthesized by means of shape-supported cyclization, starting from H-shaped precursors via the alternative Friedel-Crafts reactions of fluorenols and Suzuki cross-coupling reactions with key cyclization yields up to 26%. Fluorenol approaches and nanogrids open a door to soluble one-, two-, or three-dimensional nanoporous polymers as next-generation polymer mechano-semiconductors facing a new era of consciousness.

13.
ACS Chem Biol ; 8(2): 423-31, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23130658

RESUMO

Cyclic peptides hold great potential as therapeutic agents and research tools, but their broad application has been limited by poor membrane permeability. Here, we report a potentially general approach for intracellular delivery of cyclic peptides. Short peptide motifs rich in arginine and hydrophobic residues (e.g., FΦRRRR, where Φ is l-2-naphthylalanine), when embedded into small- to medium-sized cyclic peptides (7-13 amino acids), bound to the plasma membrane of mammalian cultured cells and were subsequently internalized by the cells. Confocal microscopy and a newly developed peptide internalization assay demonstrated that cyclic peptides containing these transporter motifs were translocated into the cytoplasm and nucleus at efficiencies 2-5-fold higher than that of nonaarginine (R(9)). Furthermore, incorporation of the FΦRRRR motif into a cyclic peptide containing a phosphocoumaryl aminopropionic acid (pCAP) residue generated a cell permeable, fluorogenic probe for detecting intracellular protein tyrosine phosphatase activities.


Assuntos
Sistemas de Liberação de Medicamentos , Peptídeos Cíclicos/química , Peptídeos Cíclicos/metabolismo , Motivos de Aminoácidos , Membrana Celular/metabolismo , Humanos , Células MCF-7 , Microscopia Confocal , Conformação Molecular , Peptídeos Cíclicos/síntese química , Células Tumorais Cultivadas
14.
Thyroid ; 22(6): 617-24, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22540327

RESUMO

BACKGROUND: Micro-single-photon emission computed tomography (SPECT) provides a noninvasive way to evaluate the effects of genetic and/or pharmacological modulation on sodium-iodide symporter (NIS)-mediated radionuclide accumulation in mouse thyroid and salivary glands. However, parameters affecting image acquisition and analysis of mouse thyroids and salivary glands have not been thoroughly investigated. In this study, we investigated the effects of region-of-interest (ROI) selection, collimation, scan time, and imaging orbit on image acquisition and quantification of thyroidal and salivary radionuclide accumulation in mice. METHODS: The effects of data window minima and maxima on thyroidal and salivary ROI selection using a visual boundary method were examined in SPECT images acquired from mice injected with (123)I NaI. The effects of collimation, scan time, and imaging orbit on counting linearity and signal intensity were investigated using phantoms filled with various activities of (123)I NaI or Tc-99m pertechnetate. Spatial resolution of target organs in whole-animal images was compared between circular orbit with parallel-hole collimation and spiral orbit with five-pinhole collimation. Lastly, the inter-experimental variability of the same mouse scanned multiple times was compared with the intra-experimental variability among different mice scanned at the same time. RESULTS: Thyroid ROI was separated from salivary glands by empirically increasing the data window maxima. Counting linearity within the range of 0.5-14.2 µCi was validated by phantom imaging using single- or multiple-pinhole collimators with circular or spiral imaging orbit. Scanning time could be shortened to 15 minutes per mouse without compromising counting linearity despite proportionally decreased signal intensity. Whole-animal imaging using a spiral orbit with five-pinhole collimators achieved a high spatial resolution and counting linearity. Finally, the extent of inter-experimental variability of NIS-mediated radionuclide accumulation in the thyroid and salivary glands by SPECT imaging in the same mouse was less than the magnitude of variability among the littermates. CONCLUSIONS: The impacts of multiple variables and experimental designs on micro-SPECT imaging and quantification of radionuclide accumulation in mouse thyroid and salivary glands can be minimized. This platform will serve as an invaluable tool to screen for pharmacologic reagents that differentially modulate thyroidal and salivary radioiodine accumulation in preclinical mouse models.


Assuntos
Radioisótopos do Iodo/metabolismo , Glândulas Salivares/diagnóstico por imagem , Glândulas Salivares/metabolismo , Simportadores/metabolismo , Glândula Tireoide/diagnóstico por imagem , Glândula Tireoide/metabolismo , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Animais , Injeções , Radioisótopos do Iodo/administração & dosagem , Camundongos , Camundongos Endogâmicos , Modelos Animais , Imagens de Fantasmas , Reprodutibilidade dos Testes , Pertecnetato Tc 99m de Sódio/administração & dosagem , Pertecnetato Tc 99m de Sódio/metabolismo
15.
Endocr Relat Cancer ; 19(3): 291-304, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22355179

RESUMO

The selective increase of Na(+)/I(-) symporter (NIS)-mediated active iodide uptake in thyroid cells allows the use of radioiodine I(131) for diagnosis and targeted treatment of thyroid cancers. However, NIS-mediated radioiodine accumulation is often reduced in thyroid cancers due to decreased NIS expression/function. As PI3K signaling is overactivated in many thyroid tumors, we investigated the effects of inhibitors for PI3K, Akt, or mTORC1 as well as their interplay on NIS modulation in thyroid cells under chronic TSH stimulation. PI3K inhibition by LY294002 increased NIS-mediated radioiodide uptake (RAIU) mainly through upregulation of NIS expression, however, mTORC1 inhibition by Rapamycin did not increase NIS-mediated RAIU despite increased NIS protein levels. In comparison, Akt inhibition by Akti-1/2 did not increase NIS protein levels, yet markedly increased NIS-mediated RAIU by decreasing iodide efflux rate and increasing iodide transport rate and iodide affinity of NIS. The effects of Akti-1/2 on NIS-mediated RAIU are not detected in nonthyroid cells, implying that Akti-1/2 or its derivatives may represent potential pharmacological reagents to selectively increase thyroidal radioiodine accumulation and therapeutic efficacy.


Assuntos
Benzilaminas/farmacologia , Cromonas/farmacologia , Radioisótopos do Iodo/metabolismo , Morfolinas/farmacologia , Quinoxalinas/farmacologia , Sirolimo/farmacologia , Simportadores/metabolismo , Animais , Proteínas Quinases Dependentes de Cálcio-Calmodulina/antagonistas & inibidores , Linhagem Celular , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Células HEK293 , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina , Complexos Multiproteicos , Proteínas/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , RNA Mensageiro/metabolismo , Ratos , Simportadores/genética , Serina-Treonina Quinases TOR , Glândula Tireoide/citologia , Tireotropina/farmacologia
16.
Endocrinology ; 152(3): 782-92, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21209020

RESUMO

Na(+)/I(-) symporter (NIS)-mediated iodide uptake into thyroid follicular cells serves as the basis of radioiodine therapy for thyroid cancer. NIS protein is also expressed in the majority of breast tumors, raising potential for radionuclide therapy of breast cancer. KT5823, a staurosporine-related protein kinase inhibitor, has been shown to increase thyroid-stimulating hormone-induced NIS expression, and thus iodide uptake, in thyroid cells. In this study, we found that KT5823 does not increase but decreases iodide uptake within 0.5 h of treatment in trans-retinoic acid and hydrocortisone-treated MCF-7 breast cancer cells. Moreover, KT5823 accumulates hypoglycosylated NIS, and this effect is much more evident in breast cancer cells than thyroid cells. The hypoglycosylated NIS is core glycosylated, has not been processed through the Golgi apparatus, but is capable of trafficking to the cell surface. KT5823 impedes complex NIS glycosylation at a regulatory point similar to brefeldin A along the N-linked glycosylation pathway, rather than targeting a specific N-glycosylated site of NIS. KT5823-mediated effects on NIS activity and glycosylation are also observed in other breast cancer cells as well as human embryonic kidney cells expressing exogenous NIS. Taken together, KT5823 will serve as a valuable pharmacological reagent to uncover mechanisms underlying differential NIS regulation between thyroid and breast cancer cells at multiple levels.


Assuntos
Neoplasias da Mama/metabolismo , Carbazóis/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Simportadores/metabolismo , Glândula Tireoide/citologia , Animais , Brefeldina A/farmacologia , Linhagem Celular , Feminino , Glicosilação , Humanos , Hidrocortisona , Iodetos/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores da Síntese de Proteínas/farmacologia , Ratos , Tireotropina , Tretinoína
17.
J Bone Miner Metab ; 29(2): 149-58, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20686802

RESUMO

The present study was designed to investigate the effects of captopril, an angiotensin-converting enzyme inhibitor (ACEI), on bone loss in aged ovariectomized (OVX) rats and its impact on the differentiation of cultured primary osteoblasts. Ten-month-old female Sprague-Dawley rats were used for the study. After 2 months post ovariectomy (OVX), the rats were treated with captopril (1 or 5 mg/kg/day, respectively) for another 2 months. At endpoint, trabecular bone of the fourth lumbar vertebrae (L4) was undecalcified and examined by bone histomorphometry; the fifth lumbar vertebrae (L5) were examined by compression test. Primary osteoblasts were isolated from the calvaria of newborn rats and treated with different concentrations of captopril in a different durations. The content of secreted alkaline phosphatase (ALP) and mRNA expression of collagen I in osteoblasts were determined to demonstrate osteoblast bone formation. In aged rats with estrogen deficiency-induced osteopenia, captopril increased the trabecular area (%BV/TV) of L4 up to 33% and improved biomechanical properties by increasing L5 break stress and elastic modulus when compared to those in the OVX group (P < 0.01). Captopril showed dose-dependent effects on promoting the secretion of ALP and increased mRNA expression of collagen I in the cultured rat osteoblasts. In summary, captopril, one of the most widely used ACEIs, has the potential effects of improving lumbar vertebral bone strength in aged OVX rats and promoting osteoblast bone formation in vitro.


Assuntos
Doenças Ósseas Metabólicas/tratamento farmacológico , Captopril/farmacologia , Captopril/uso terapêutico , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Animais , Fenômenos Biomecânicos/efeitos dos fármacos , Doenças Ósseas Metabólicas/metabolismo , Células Cultivadas , Feminino , Ovariectomia , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Endocr Relat Cancer ; 18(1): 27-37, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20943721

RESUMO

Selective iodide uptake and prolonged iodine retention in the thyroid is the basis for targeted radioiodine therapy for thyroid cancer patients; however, salivary gland dysfunction is the most frequent nonthyroidal complications. In this study, we have used noninvasive single photon emission computed tomography functional imaging to quantify the temporal dynamics of thyroidal and salivary radioiodine accumulation in mice. At 60  min post radionuclide injection, radionuclide accumulation in the salivary gland was generally higher than that in thyroid due to much larger volume of the salivary gland. However, radionuclide accumulation per anatomic unit in the salivary gland was lower than that in thyroid and was comparable among mice of different age and gender. Differently, radionuclide accumulation per anatomic unit in thyroid varied greatly among mice. The extent of thyroidal radioiodine accumulation stimulated by a single dose of exogenous bovine TSH (bTSH) in triiodothyronine (T3)-supplemented mice was much less than that in mice received neither bTSH nor T3 (nontreated mice), suggesting that the duration of elevated serum TSH level is important to maximize thyroidal radioiodine accumulation. Furthermore, the extent and duration of radioiodine accumulation stimulated by bTSH was less in the thyroids of the thyroid-targeted RET/PTC1 (thyroglobulin (Tg)-PTC1) mice bearing thyroid tumors compared with the thyroids in wild-type (WT) mice. Finally, the effect of 17-allyamino-17-demothoxygeldanamycin on increasing thyroidal, but not salivary, radioiodine accumulation was validated in both WT mice and Tg-PTC1 preclinical thyroid cancer mouse model.


Assuntos
Benzoquinonas/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Lactamas Macrocíclicas/farmacologia , Glândulas Salivares/diagnóstico por imagem , Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Animais , Modelos Animais de Doenças , Imagem Tridimensional , Camundongos , Receptores Patched , Receptor Patched-1 , Receptores de Superfície Celular/fisiologia , Tireotropina/farmacologia
19.
Acta Pharmacol Sin ; 30(3): 321-32, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19262556

RESUMO

AIM: Previous studies have shown that D(+)beta-3,4-dihydroxyphenyl lactic acid (salvianic acid A, SAA) has anabolic effects on prednisone (GC)-induced osteoporosis in rats. The current study aims to investigate the molecular mechanism of SAA's impact on osteogenesis and adipogenesis in bone marrow stromal cells in intact and GC-treated rats. METHODS: For in vitro study, newborn rat calvaria osteoblasts (rOBs) and rat bone marrow stromal cells (rMSCs) were isolated, identified and cultured with SAA at different concentrations to evaluate SAA's influence on osteogenesis and adipogenesis. In addition, 3-month-old Sprague-Dawley (SD) male rats were treated with distilled water, prednisone alone (3.0 mgxkg(-1)xd(-1)) or prednisone (3.0 mgxkg(-1)xd(-1)) and SAA (25 mgxkg(-1)xd(-1)) for 45 d. At the end point, the different groups of rMSCs were isolated by density-gradient centrifugation and cultured. RESULTS: (1) At 0.1-10.0 mg/L, SAA increased ALP activity, type I collagen (Coll-I) mRNA and OPG mRNA expression and stimulated nodule mineralization of rOBs. SAA (0.5 mg/L) also significantly increased the ALP activity of rMSCs without a need for osteogenesis-inducing medium. At 5.0 mg/L, SAA decreased the number of adipocytes with less lipid droplet formation from the rMSCs, which typically undergo adipocyte induction. (2) Coll-I expression was markedly decreased, whereas lipoprotein lipase (LPL) mRNA expression increased by 98% when compared with the first generation of rMSCs in GC-treated rats. The SAA-treated rats demonstrated an over 2-fold increase in Coll-I expression when compared with intact rats and further showed a significant decrease in LPL expression when compared with GC-treated rats. When rMSCs were co-cultured with SAA (0.5 mg/L) in vitro, SAA did not affect Coll-I and LPL gene expression in intact rats but significantly increased Coll-I and decreased LPL gene expression in GC-treated rats. CONCLUSION: SAA protected bone from GC-induced bone marrow impairment by stimulating osteogenesis and depressing adipogenesis in bone marrow stromal cells both in vivo and in vitro. The data indicated that aqueous extract of Salvia miltiorrhiza, which include SAA, may serve as an active anabolic agent and a useful therapeutic strategy for the treatment of GC-associated osteoporosis.


Assuntos
Células da Medula Óssea/efeitos dos fármacos , Ácidos Cafeicos/farmacologia , Glucocorticoides/farmacologia , Lactatos/farmacologia , Osteogênese/efeitos dos fármacos , Prednisona/farmacologia , Células Estromais/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Animais , Animais Recém-Nascidos , Células da Medula Óssea/citologia , Células da Medula Óssea/fisiologia , Diferenciação Celular/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Células Cultivadas , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Lipase Lipoproteica/genética , Lipase Lipoproteica/metabolismo , Masculino , Estrutura Molecular , Osteocalcina/metabolismo , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley , Salvia/química , Células Estromais/citologia , Células Estromais/fisiologia
20.
J Clin Endocrinol Metab ; 90(11): 6131-40, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16105966

RESUMO

CONTEXT: The Na+/I- symporter (NIS) has been proposed to serve as an imaging reporter gene to optimize vector delivery, monitor therapeutic gene expression, and map the tissue/organ sites of repopulated progenitor cells in vivo. In addition, NIS can serve as a therapeutic gene to facilitate targeted radionuclide therapy for various cancers. OBJECTIVE: It was reported that rat NIS (rNIS) confers higher radioactive iodide uptake (RAIU) activity than human NIS (hNIS). We aim to investigate the mechanism underlying this difference. RESULTS: We showed that the open reading frames (ORF) of hNIS and rNIS, although encoding for proteins with 83% amino acid identity, exhibit a significant difference in RAIU activity in transfected cells. The ORF rNIS confers four to five times higher RAIU activity as well as cell surface NIS accumulation than ORF hNIS despite similar total NIS protein levels. Multiple regions appear to play roles in the difference in NIS cell surface levels between ORF hNIS and ORF rNIS, indicating that proper folding of NIS in tertiary structure is critical for NIS cell surface targeting. We also showed that the kinetics of Na+ binding are different between ORF hNIS and ORF rNIS, and that site-directed mutation changing Ser200 to other uncharged amino acid significantly increased RAIU activity in ORF hNIS. CONCLUSIONS: NIS transgene could be optimized for cell surface trafficking and RAIU activity to improve its clinical applications.


Assuntos
Iodetos/metabolismo , Simportadores/fisiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Células COS , Humanos , Dados de Sequência Molecular , Fases de Leitura Aberta , Ratos , Sódio/metabolismo , Especificidade da Espécie , Relação Estrutura-Atividade , Simportadores/química , Simportadores/genética
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