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1.
Proc Natl Acad Sci U S A ; 119(26): e2201490119, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35733270

RESUMO

Excess bone loss due to increased osteoclastogenesis is a significant clinical problem. Intraflagellar transport (IFT) proteins have been reported to regulate cell growth and differentiation. The role of IFT80, an IFT complex B protein, in osteoclasts (OCs) is completely unknown. Here, we demonstrate that deletion of IFT80 in the myeloid lineage led to increased OC formation and activity accompanied by severe bone loss in mice. IFT80 regulated OC formation by associating with Casitas B-lineage lymphoma proto-oncogene-b (Cbl-b) to promote protein stabilization and proteasomal degradation of tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6). IFT80 knockdown resulted in increased ubiquitination of Cbl-b and higher TRAF6 levels, thereby hyperactivating the receptor activator of nuclear factor-κß (NF-κß) ligand (RANKL) signaling axis and increased OC formation. Ectopic overexpression of IFT80 rescued osteolysis in a calvarial model of bone loss. We have thus identified a negative function of IFT80 in OCs.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Reabsorção Óssea , Proteínas de Transporte , Osteoclastos , Osteogênese , Proteínas Proto-Oncogênicas c-cbl , Fator 6 Associado a Receptor de TNF , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Reabsorção Óssea/genética , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Diferenciação Celular , Modelos Animais de Doenças , Deleção de Genes , Camundongos , Osteoclastos/citologia , Osteoclastos/metabolismo , Osteogênese/genética , Proteólise , Proteínas Proto-Oncogênicas c-cbl/metabolismo , Ligante RANK/genética , Ligante RANK/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Ubiquitinação
2.
Mol Med ; 30(1): 111, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39085816

RESUMO

BACKGROUND: Osteoclast hyperactivation due to the pathological overproduction of reactive oxygen species (ROS) stimulated by glucocorticoids (GCs) is one of the key drivers behind glucocorticoid-induced osteonecrosis of the femoral head (GIONFH). The insulin degrading enzyme (IDE), a conserved Zn2+ metallo-endopeptidase, facilitates the DNA binding of glucocorticoid receptor and plays a substantial role in steroid hormone-related signaling pathways. However, the potential role of IDE in the pathogenesis of GIONFH is yet undefined. METHODS: In this study, we employed network pharmacology and bioinformatics analysis to explore the impact of IDE inhibition on GIONFH with 6bK as an inhibitory agent. Further evidence was collected through in vitro osteoclastogenesis experiments and in vivo evaluations involving methylprednisolone (MPS)-induced GIONFH mouse model. RESULTS: Enrichment analysis indicated a potential role of 6bK in redox regulation amid GIONFH development. In vitro findings revealed that 6bK could attenuate GCs-stimulated overactivation of osteoclast differentiation by interfering with the transcription and expression of key osteoclastic genes (Traf6, Nfatc1, and Ctsk). The use of an H2DCFDA probe and subsequent WB assays introduced the inhibitory effects of 6bK on osteoclastogenesis, linked with the activation of the nuclear factor erythroid-derived 2-like 2 (Nrf2)-mediated antioxidant system. Furthermore, Micro-CT scans validated that 6bK could alleviate GIONFH in MPS-induced mouse models. CONCLUSIONS: Our findings suggest that 6bK suppresses osteoclast hyperactivity in GCs-rich environment. This is achieved by reducing the accumulation of intracellular ROS via promoting the Nrf2-mediated antioxidant system, thus implying that IDE could be a promising therapeutic target for GIONFH.


Assuntos
Modelos Animais de Doenças , Necrose da Cabeça do Fêmur , Glucocorticoides , Fator 2 Relacionado a NF-E2 , Osteoclastos , Animais , Fator 2 Relacionado a NF-E2/metabolismo , Camundongos , Osteoclastos/metabolismo , Osteoclastos/efeitos dos fármacos , Necrose da Cabeça do Fêmur/metabolismo , Necrose da Cabeça do Fêmur/induzido quimicamente , Necrose da Cabeça do Fêmur/etiologia , Necrose da Cabeça do Fêmur/patologia , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Masculino , Osteogênese/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Osteonecrose/metabolismo , Osteonecrose/induzido quimicamente
3.
J Sci Food Agric ; 104(7): 4342-4353, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38328855

RESUMO

BACKGROUND: Non-nutritive sweeteners (NNS) are commonly used in sweetened foods and beverages; however their role in metabolic regulation is still not clear. In this experiment, we used guinea pigs as an animal model to study the effect of NNS on body growth and intestinal health by modifying gut microbiota and hypothalamus-related proteins. RESULTS: For a 28-day feeding experiment a total of 40 guinea pigs were randomly divided into four groups, one control (CN) group and three treatments, in which three NNS were added to the diet: rebaudioside A (RA, 330 mg kg-1), sodium saccharin (SS, 800 mg kg-1), and sucralose (TGS, 167 mg kg-1), respectively. The TGS group exhibited significantly reduced food consumption in comparison with the CN group (P < 0.05) whereas the RA group showed increased food consumption in comparison with the CN group (P < 0.05). Notably, Taste receptor type 1 subunit 2 (T1R2) expression in the hypothalamus was significantly higher in the RA group than in the CN group (P < 0.05). The mRNA expressions of appetite-stimulated genes arouti-related neuropeptide (AGRP), neuropeptide Y (NPY), and thyroid stimulating hormone (TSHB) were significantly higher than those in the CN group (P < 0.05) but mRNA expressions of appetite-suppressed genes tryptophan hydroxylase 2(THP2) were significantly lower in the TGS group (P < 0.05). Furthermore, NNS in the guinea pig diets (RA, SS, TGS) significantly increased the relative abundance of Muribaculaceae but decreased the relative abundance of Clostridia_vadin BB60 in comparison with the CN group (P < 0.05). We also found that dietary supplementation with RA also significantly altered the relative abundance of Lactobacillus. CONCLUSION: Our finding confirmed that dietary supplementation with RA and TGS affected body growth and intestinal health by modulating hypothalamic RNA profiles and ileum microbiota, suggesting that NNS should be included in guinea-pig feeding. © 2024 Society of Chemical Industry.


Assuntos
Microbioma Gastrointestinal , Adoçantes não Calóricos , Cobaias , Animais , Peso Corporal , Íleo , RNA Mensageiro
4.
Angew Chem Int Ed Engl ; 63(32): e202405560, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38787342

RESUMO

Radical-involved multicomponent difunctionalization of 1,3-dienes has recently emerged as a promising strategy for rapid synthesis of valuable allylic compounds in one-pot operation. However, the expansion of radical scope and enantiocontrol remain two major challenges. Herein, we describe an unprecedented photoinduced copper-catalyzed highly enantioselective three-component radical 1,2-azidooxygenation of 1,3-dienes with readily available azidobenziodazolone reagent and carboxylic acids. This mild protocol exhibits a broad substrate scope, high functional group tolerance, and exceptional control over chemo-, regio- and enantioselectivity, providing practical access to diverse valuable azidated chiral allylic esters. Mechanistic studies imply that the chiral copper complex is implicated as a bifunctional catalyst in both the photoredox catalyzed azidyl radical generation and enantioselective radical C-O cross-coupling.

5.
Small ; 19(9): e2206310, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36587965

RESUMO

2D Ruddlesden-Popper perovskites (PVKs) have recently shown overwhelming potential in various optoelectronic devices on account of enhanced stability to their 3D counterparts. So far, regulating the phase distribution and orientation of 2D perovskite thin films remains challenging to achieve efficient charge transport. This work elucidates the balance struck between sufficient gradient sedimentation of perovskite colloids and less formation of small-n phases, which results in the layered alignment of phase compositions and thus in enhanced photoresponse. The solvent engineering strategy, together with the introduction of poly(3,4-ethylene-dioxythiophene):polystyrene sulfonate (PEDOT:PSS) and PC71 BM layer jointly contribute to outstanding self-powered performance of indium tin oxide/PEDOT:PSS/PVK/PC71 BM/Ag device, with a photocurrent of 18.4 µA and an on/off ratio up to 2800. The as-fabricated photodetector exhibits high sensitivity characteristics with the peak responsivity of 0.22 A W-1 and the detectivity up to 1.3 × 1012  Jones detected at UV-A region, outperforming most reported perovskite-based UV photodetectors and maintaining high stability over a wide spectrum ranging from UV to visible region. This discovery supplies deep insights into the control of ordered phases and crystallinity in quasi-2D perovskite films for high-performance optoelectronic devices.

6.
Nano Lett ; 22(21): 8662-8669, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36314926

RESUMO

2D halide perovskites feature solution processability and tunable optoelectronic properties for optoelectronic applications. However, the controllable fabrication of halide perovskite heterojunction still remains a challenge. Herein, through controlling surface tension and nucleation driving force, a fast and facile aqueous floating growth is demonstrated to obtain a series of large-area single-crystalline 2D perovskite microplates at room temperature. The optoelectronic performance of 2D perovskites can be tuned by composition engineering, and the best performance is realized for quantum well index n = 4, including a suppressed dark current with boosted photocurrent and an on/off ratio up to 3.5 orders of magnitude. Benefiting from a convenient transfer method onto arbitrary substrates, vertically oriented 2D perovskite hetero-/homo-junctions are gently stacked, which exhibit improved self-powered characteristics. This straightforward growth strategy is an universal solution-processed method for growing 2D perovskites, laying the foundation of the 2D perovskite hetero-/homo-junction for future miniaturization and functionalization of next-generation optoelectronics.

7.
Molecules ; 28(5)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36903498

RESUMO

Phthalocyanines are potentially promising photosensitizers (PSs) for photodynamic therapy (PDT), but the inherent defects such as aggregation-caused quenching effects and non-specific toxicity severely hinder their further application in PDT. Herein, we synthesized two zinc(II) phthalocyanines (PcSA and PcOA) monosubstituted with a sulphonate group in the alpha position with "O bridge" and "S bridge" as bonds and prepared a liposomal nanophotosensitizer (PcSA@Lip) by thin-film hydration method to regulate the aggregation of PcSA in the aqueous solution and enhance its tumor targeting ability. PcSA@Lip exhibited highly efficient production of superoxide radical (O2∙-) and singlet oxygen (1O2) in water under light irradiation, which were 2.6-fold and 15.4-fold higher than those of free PcSA, respectively. Furthermore, PcSA@Lip was able to accumulate selectively in tumors after intravenous injection with the fluorescence intensity ratio of tumors to livers was 4.1:1. The significant tumor inhibition effects resulted in a 98% tumor inhibition rate after PcSA@Lip was injected intravenously at an ultra-low PcSA@Lip dose (0.8 nmol g-1 PcSA) and light dose (30 J cm-2). Therefore, the liposomal PcSA@Lip is a prospective nanophotosensitizer possessing hybrid type I and type II photoreactions with efficient photodynamic anticancer effects.


Assuntos
Fotoquimioterapia , Zinco , Estudos Prospectivos , Fármacos Fotossensibilizantes/química , Isoindóis , Enxofre
8.
Int J Mol Sci ; 23(14)2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35887125

RESUMO

Nonlinear dimensionality reduction (NLDR) methods such as t-Distributed Stochastic Neighbour Embedding (t-SNE) and Uniform Manifold Approximation and Projection (UMAP) have been widely used for biological data exploration, especially in single-cell analysis. However, the existing methods have drawbacks in preserving data's geometric and topological structures. A high-dimensional data analysis method, called Panoramic manifold projection (Panoramap), was developed as an enhanced deep learning framework for structure-preserving NLDR. Panoramap enhances deep neural networks by using cross-layer geometry-preserving constraints. The constraints constitute the loss for deep manifold learning and serve as geometric regularizers for NLDR network training. Therefore, Panoramap has better performance in preserving global structures of the original data. Here, we apply Panoramap to single-cell datasets and show that Panoramap excels at delineating the cell type lineage/hierarchy and can reveal rare cell types. Panoramap can facilitate trajectory inference and has the potential to aid in the early diagnosis of tumors. Panoramap gives improved and more biologically plausible visualization and interpretation of single-cell data. Panoramap can be readily used in single-cell research domains and other research fields that involve high dimensional data analysis.


Assuntos
Algoritmos , Redes Neurais de Computação , Análise de Célula Única
9.
Can J Physiol Pharmacol ; 99(9): 900-909, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33529089

RESUMO

Vascular endothelial cell senescence is a leading cause of age-associated diseases and cardiovascular diseases. Interventions and therapies targeting endothelial cell senescence and dysfunction would have important clinical implications. This study evaluated the effect of 10 resveratrol analogues, including pterostilbene (Pts) and its derivatives, against endothelial senescence and dysfunction. All the tested compounds at the concentrations from 10-9 M to 10-6 M did not show cytotoxicity in endothelial cells by MTT assay. Among the 10 resveratrol analogues, Pts and Pts nicotinate attenuated the expression of senescence-associated ß-galactosidase, downregulated p21 and p53, and increased the production of nitric oxide (NO) in both angiotensin II - and hydrogen peroxide - induced endothelial senescence models. In addition, Pts and Pts nicotinate elicited endothelium-dependent relaxations, which were attenuated in the presence of endothelial NO synthase (eNOS) inhibitor L-NAME or sirtuin 1 (SIRT1) inhibitor sirtinol. Pts and Pts nicotinate did not alter SIRT1 expression but enhanced its activity. Both Pts and Pts nicotinate have high binding activities with SIRT1, according to surface plasmon resonance results and the molecular docking analysis. Inhibition of SIRT1 by sirtinol reversed the anti-senescent effects of Pts and Pts nicotinate. Moreover, Pts and Pts nicotinate shared similar ADME (absorption, distribution, metabolism, excretion) profiles and physiochemical properties. This study suggests that the Pts and Pts nicotinate ameliorate vascular endothelial senescence and elicit endothelium-dependent relaxations via activation of SIRT1. These two compounds may be potential drugs for the treatment of cardiovascular diseases related to endothelial senescence and dysfunction.


Assuntos
Senescência Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Resveratrol/análogos & derivados , Sirtuína 1/fisiologia , Estilbenos/farmacologia , Vasodilatação/efeitos dos fármacos , Animais , Células Cultivadas , Células Endoteliais/fisiologia , Humanos , Masculino , Niacina/análogos & derivados , Ratos , Ratos Sprague-Dawley
10.
Inorg Chem ; 57(3): 935-950, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29356513

RESUMO

The europium ion probes the symmetry disorder in the crystal structure, although the distortion due to charge compensation in the case of aliovalent dopant remains interesting, especially preparation involves low and high temperatures. This work studies the preparation of the ß-Ca2SiO4 (from here on C2S) particle from Pechini (C2SP) and hydrothermal (C2SH) methods, and its luminescence variance upon doping with Eu2+ and Eu3+ ions. The blue shift of the charge-transfer band (CTB) in the excitation spectra indicates a larger Eu3+-O2- distance in Eu3+ doped C2SH. The changes in vibrational frequencies due to stretching and bending vibrations in the FTIR and the Raman spectra and binding energy shift in the XPS analysis confirmed the distorted SiO44- tetrahedra in C2SH. The high hydrothermal temperature and pressure produce distortion, which leads to symmetry lowering although doping of aliovalent ion may slightly change the position of the Ca atoms. The increasing asymmetry ratio value from C2SP to C2SH clearly indicates that the europium ion stabilized in a more distorted geometry. It is also supported by Judd-Ofelt analysis. The concentration quenching and site-occupancy of Eu3+ ions in two nonequivalent sites of C2S were discussed. The charge state and concentration of europium ions in C2SP and C2SH were determined using X-ray photoelectron spectroscopy measurements. The C2S particles were studied by X-ray powder diffraction, FTIR, Raman, BET surface area, TGA/DTA, electron microscopy, XPS, and luminescence spectroscopy. The impact of citrate ion on the morphology and particle size of C2SH has been hypothesized on the basis of the microscopy images. This study provides insights that are needed for further understanding the structure of C2S and thereby improves the applications in optical and biomedical areas and cement hydration.

11.
Acta Pharmacol Sin ; 39(12): 1837-1846, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29991711

RESUMO

Vascular endothelial cell senescence is a leading cause of age-associated and vascular diseases. Mammalian target of rapamycin complex 2 (mTORC2) is a conserved serine/threonine (Ser/Thr) protein kinase that plays an important regulatory role in various cellular processes. However, its impact on endothelial senescence remains controversial. In this study we investigated the role and molecular mechanisms of mTORC2 in endothelial senescence. A replicative senescence model and H2O2-induced premature senescence model were established in primary cultured human umbilical vein endothelial cells (HUVECs). In these senescence models, the formation and activation of mTORC2 were significantly increased, evidenced by the increases in binding of Rictor (the essential component of mTORC2) to mTOR, phosphorylation of mTOR at Ser2481 and phosphorylation of Akt (the effector of mTORC2) at Ser473. Knockdown of Rictor or treatment with the Akt inhibitor MK-2206 attenuated senescence-associated ß-galactosidase (ß-gal) staining and expression of p53 and p21 proteins in the senescent endothelial cells, suggesting that mTORC2/Akt facilitates endothelial senescence. The effect of mTORC2/Akt on endothelial senescence was due to suppression of nuclear factor erythroid 2-related factor 2 (Nrf2) at the transcriptional level, since knockdown of Rictor reversed the reduction of Nrf2 mRNA expression in endothelial senescence. Furthermore, mTORC2 suppressed the expression of Nrf2 via the Akt/GSK-3ß/C/EBPα signaling pathway. These results suggest that the mTORC2/Akt/GSK-3ß/C/EBPα/Nrf2 signaling pathway is involved in both replicative and inducible endothelial senescence. The deleterious role of mTORC2 in endothelial cell senescence suggests therapeutic strategies (targeting mTORC2) for aging-associated diseases and vascular diseases.


Assuntos
Senescência Celular/fisiologia , Células Endoteliais/fisiologia , Alvo Mecanístico do Complexo 2 de Rapamicina/fisiologia , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/fisiologia
12.
Am J Physiol Endocrinol Metab ; 310(5): E355-66, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26670486

RESUMO

Advanced glycation end products (AGEs) disturb bone remodeling during aging, and this process is accelerated in diabetes. However, their role in modulation of osteoclast-induced bone resorption is controversial, with some studies indicating that AGEs enhance bone resorption and others showing the opposite effect. We determined whether AGEs present at different stages of osteoclast differentiation affect bone resorption differently. Based on increased levels of tartrate-resistant acid phosphatase (TRAP) and cathepsin K (CTSK), we identified day 4 of induction as the dividing time of cell fusion stage and mature stage in RAW264.7 cell-derived osteoclast-like cells (OCLs). AGE-modified BSA (50-400 µg/ml) or control BSA (100 µg/ml) was then added at the beginning of each stage. Results showed that the presence of AGEs at the cell fusion stage reduced pit numbers, resorption area, and CTSK expression. Moreover, expression of receptor activator of nuclear factor-κB (RANK) as well as the number of TRAP-positive cells, nuclei per OCL, actin rings, and podosomes also decreased. However, the presence of AGEs at the mature stage enlarged the resorption area markedly and increased pit numbers slightly. Intriguingly, only the number of nuclei per OCL and podosomes increased. These data indicate that AGEs biphasically modulate bone resorption activity of OCLs in a differentiation stage-dependent manner. AGEs at the cell fusion stage reduce bone resorption dramatically, mainly via suppression of RANK expression in osteoclast precursors, whereas AGEs at the mature stage enhance bone resorption slightly, most likely by increasing the number of podosomes in mature OCLs.


Assuntos
Remodelação Óssea/efeitos dos fármacos , Reabsorção Óssea/metabolismo , Diferenciação Celular/efeitos dos fármacos , Produtos Finais de Glicação Avançada/farmacologia , Osteoclastos/efeitos dos fármacos , Fosfatase Ácida/metabolismo , Actinas/efeitos dos fármacos , Actinas/metabolismo , Animais , Western Blotting , Catepsina K/metabolismo , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Imuno-Histoquímica , Isoenzimas/metabolismo , Camundongos , Osteoclastos/citologia , Osteoclastos/metabolismo , Podossomos/efeitos dos fármacos , Podossomos/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptor Ativador de Fator Nuclear kappa-B/efeitos dos fármacos , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Fosfatase Ácida Resistente a Tartarato
13.
Cell Physiol Biochem ; 39(2): 709-20, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27448695

RESUMO

BACKGROUND/AIMS: Hypoxia leads to the development of neovascularization in solid tumor by regulating VEGF expression. Aromatic hydrocarbon receptor (AHR), a receptor for dioxin-like compounds, functions as a transcription factor through dimerization with hypoxia-inducible factors 1ß (HIF-1ß) and inhibits the secretion of vascular endothelial growth factor (VEGF). The purpose of this study was to explore whether AHR can suppress hypoxia-induced VEGF production in prostate bone metastasis cells and repress neovascularization in endothelial progenitor cells (EPCs), and, if so, through what mechanisms. METHODS: PC-3 or LNCaP cells induced angiogenesis was detected by Matrigel-based tube formation assay, mRNA expression levels was measured by qRT-PCR, VEGF secretion level was determined by ELISA assay, respectively. RESULTS: AHR activation inhibits hypoxia-induced adhesiveness and vasculogenesis of EPCs induced by PC-3 or LNCaP cells under hypoxia. Moreover, AHR activation suppressed hypoxia-induced VEGF production in PC-3 and LNCaP cells (48 ± 14% in PC-3, p = 0.000; 41 ± 14% in LNCaP, p = 0.000) by attenuating HIF-1α and HIF-1ß level that in turn diminished the angiogenic ability of EPCs in vitro. Furthermore, we found the mRNA level of hypoxia-inducible factors 1α (HIF-1α) (1.54 ± 0.13 fold in PC-3, p = 0.002, 1.62 ± 0.12 fold in LNCaP, p = 0.001) and HIF-1ß (1.67 ± 0.23 fold in PC-3, p = 0.007; 1.75 ± 0.26 fold in LNCaP, p=0.008) were upregulated in prostate cancer bone metastasis PC-3 and LNCaP cell lines in response to hypoxia, and revealed that the regulation of VEGF by HIF-1α and HIF-1ß was possibly mediated by the activation of phosphatidylinositol 3-kinase pathway. CONCLUSION: By providing a mechanistic insight into the modulation of neovascularization by AHR ligand, we suggest that AHR ligand has a strong potential of being a new therapeutic agent with applications in the field of bone metastatic prostate cancer.


Assuntos
Células Progenitoras Endoteliais/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Fator A de Crescimento do Endotélio Vascular/genética , Idoso , Idoso de 80 Anos ou mais , Translocador Nuclear Receptor Aril Hidrocarboneto/genética , Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/secundário , Adesão Celular/genética , Hipóxia Celular , Linhagem Celular , Linhagem Celular Tumoral , Células Cultivadas , Técnicas de Cocultura , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Interferência de RNA , Receptores de Hidrocarboneto Arílico/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/metabolismo
14.
Cell Physiol Biochem ; 35(5): 1857-67, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25871260

RESUMO

BACKGROUND/AIMS: Prosthesis loosening is closely associated with chronic inflammatory cytokine secretion by macrophages, which are activated by wear particles or inflammatory stimulants such as lipopolysaccharide (LPS). Reactive oxygen species (ROS) are critical regulators of inflammation, but their enzymatic sources in response to wear particles and their effects on peri-implant LPS-tolerance remain unclear. METHODS: Three ROS-related enzymes-nicotinamide adenine dinucleotide phosphate oxidase (NOX)-1 and -2 and catalase-were investigated in interface membrane tissues and in titanium (Ti) particle-stimulated macrophages in vitro. The generation of ROS and downstream inflammatory effects were measured with or without pre-incubation with apocynin, an NOX inhibitor. RESULTS: Pre-exposure to Ti particles attenuated NF-κB activation in LPS-stimulated macrophages, indicating that wear particles suppress immune response, which may lead to chronic inflammation. NOX-1 and -2 were highly expressed in aseptically loosened interface membranes and in macrophages stimulated with Ti particles; the particles induced a moderate amount of ROS generation, NF-κB activation, and TNF-α secretion in macrophages, and these effects were suppressed by apocynin. CONCLUSION: Wear particles induce ROS generation through the NOX signaling pathway, resulting in persistent inflammation and delayed loosening. Thus, the suppression of NOX activity may be a useful strategy for preventing prosthesis loosening.


Assuntos
Inflamação , NADPH Oxidases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Acetofenonas/farmacologia , Adulto , Idoso , Animais , Catalase/metabolismo , Linhagem Celular , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Lipopolissacarídeos/toxicidade , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , NADPH Oxidases/antagonistas & inibidores , NF-kappa B/metabolismo , Tamanho da Partícula , Fosforilação/efeitos dos fármacos , Próteses e Implantes , Transdução de Sinais , Titânio/química , Titânio/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
15.
Eur J Orthop Surg Traumatol ; 24(2): 179-86, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23412308

RESUMO

PURPOSE: Both rotational acetabular osteotomy (RAO) and eccentric rotational acetabular osteotomy (ERAO) are effective procedures for young patients with developmental dysplasia of the hip. However, no comparative study of biomechanical changes has been reported following these two procedures. We therefore explored the stress changes on femoral head after RAO and ERAO under different load conditions. MATERIALS AND METHODS: Twelve female cadaveric hips without deformity were divided into RAO group and ERAO group. Stress value on femoral head was measured preoperatively and postoperatively after the vertical force was loaded on the cadaveric spine from 0 to 500 N. Stress change value was then calculated base on the measurements. RESULTS: In the RAO group, preoperative stress increased when loading on spine became larger, but postoperative stress changed its increasing trend into decreasing when the load was greater than 200 N (turning point). Same phenomenon was found in the ERAO group (turning point was 300 N). However, the difference between preoperative and postoperative stress was not statistically significant in both RAO and ERAO groups. Stress change value from each procedure showed similar trends. With the load growth, stress change increased firstly and then decreased, but the difference between RAO and ERAO was not statistically significant. CONCLUSIONS: Both RAO and ERAO could correct the abnormal biomechanical effect of dysplastic hip; moreover, they may have similar biomechanical effects on femoral head, obtaining the same clinical outcomes. Non-biomechanical factors (surgical trauma, technical complexity, etc.) also play important roles in procedure selection.


Assuntos
Acetábulo/fisiologia , Cabeça do Fêmur/fisiologia , Articulação do Quadril/fisiologia , Estresse Mecânico , Acetábulo/cirurgia , Adulto , Fenômenos Biomecânicos , Cadáver , Feminino , Cabeça do Fêmur/cirurgia , Articulação do Quadril/cirurgia , Humanos , Pessoa de Meia-Idade , Osteotomia/métodos , Resultado do Tratamento
16.
Asian J Pharm Sci ; 19(2): 100900, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38590797

RESUMO

Ionic liquids (ILs) have been proven to be an effective technology for enhancing drug transdermal absorption. However, due to the unique structural components of ILs, the design of efficient ILs and elucidation of action mechanisms remain to be explored. In this review, basic design principles of ideal ILs for transdermal drug delivery system (TDDS) are discussed considering melting point, skin permeability, and toxicity, which depend on the molar ratios, types, functional groups of ions and inter-ionic interactions. Secondly, the contributions of ILs to the development of TDDS through different roles are described: as novel skin penetration enhancers for enhancing transdermal absorption of drugs; as novel solvents for improving the solubility of drugs in carriers; as novel active pharmaceutical ingredients (API-ILs) for regulating skin permeability, solubility, release, and pharmacokinetic behaviors of drugs; and as novel polymers for the development of smart medical materials. Moreover, diverse action mechanisms, mainly including the interactions among ILs, drugs, polymers, and skin components, are summarized. Finally, future challenges related to ILs are discussed, including underlying quantitative structure-activity relationships, complex interaction forces between anions, drugs, polymers and skin microenvironment, long-term stability, and in vivo safety issues. In summary, this article will promote the development of TDDS based on ILs.

17.
Adv Mater ; 36(29): e2400365, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38752379

RESUMO

Deterministic integration of phase-pure Ruddlesden-Popper (RP) perovskites has great significance for realizing functional optoelectronic devices. However, precise fabrications of artificial perovskite heterostructures with pristine interfaces and rational design over electronic structure configurations remain a challenge. Here, the controllable synthesis of large-area ultrathin single-crystalline RP perovskite nanosheets and the deterministic fabrication of arbitrary 2D vertical perovskite heterostructures are reported. The 2D heterostructures exhibit intriguing dual-peak emission phenomenon and dual-band photoresponse characteristic. Importantly, the interlayer energy transfer behaviors from wide-bandgap component to narrow-bandgap component modulated by comprising quantum wells are thoroughly revealed. Functional nanoscale photodetectors are further constructed based on the 2D heterostructures. Moreover, by combining the modulated dual-band photoresponse characteristic with double-beam irradiation modes, and introducing an encryption algorithm mechanism, a light communication system with high security and reliability is achieved. This work can greatly promote the development of heterogeneous integration technologies of 2D perovskites, and could provide a competitive candidate for advanced integrated optoelectronics.

18.
Int J Pharm ; 649: 123673, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38056796

RESUMO

Ischemic heart disease (IHD) is a cardiac disorder in which myocardial damage occurs as a result of myocardial ischemia and hypoxia. Evidence suggests that oxidative stress and inflammatory responses are critical in the development of myocardial ischemia. Therefore, the combination of antioxidant and anti-inflammatory applications is an effective strategy to combat ischemic heart disease. In this paper, polyethylene glycol (PEG)-modified cationic liposomes were used as carriers to deliver apigenin (Apn) with small interfering RNA (siRNA) targeting the receptor for glycosylation end products (RAGE) (siRAGE) into cardiomyocytes to prevent myocardial ischemic injury through antioxidant and anti-inflammatory effects. Our results showed that we successfully prepared cationic PEG liposomes loaded with Apn and siRAGE (P-CLP-A/R) with normal appearance and morphology, particle size and Zeta potential, and good encapsulation rate, drug loading and in vitro release degree. In vitro, P-CLP-A/R was able to prevent oxidative stress injury in H9C2 cells, downregulate the expression of RAGE, reduce the secretion of cellular inflammatory factors and inhibit apoptosis through the RAGE/NF-κB pathway; In vivo, P-CLP-A/R was able to prevent arrhythmia and myocardial pathological injury, and reduce apoptosis and the area of necrotic myocardium in rats. In conclusion, P-CLP-A/R has a protective effect on myocardial ischemic injury and is expected to be a potential drug for the prevention of ischemic heart disease in the future.


Assuntos
Isquemia Miocárdica , Traumatismo por Reperfusão Miocárdica , Ratos , Animais , RNA Interferente Pequeno/genética , Lipossomos/farmacologia , Apigenina/farmacologia , Antioxidantes/farmacologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/metabolismo , Isquemia Miocárdica/tratamento farmacológico , Isquemia Miocárdica/prevenção & controle , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Apoptose , Anti-Inflamatórios/farmacologia
19.
Aging Cell ; 23(4): e14092, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38287696

RESUMO

Osteoarthritis (OA), a chronic degenerative joint disease, is highly prevalent among the aging population, and often leads to joint pain, disability, and a diminished quality of life. Although considerable research has been conducted, the precise molecular mechanisms propelling OA pathogenesis continue to be elusive, thereby impeding the development of effective therapeutics. Notably, recent studies have revealed subchondral bone lesions precede cartilage degeneration in the early stage of OA. This development is marked by escalated osteoclast-mediated bone resorption, subsequent imbalances in bone metabolism, accelerated bone turnover, and a decrease in bone volume, thereby contributing significantly to the pathological changes. While the role of aging hallmarks in OA has been extensively elucidated from the perspective of chondrocytes, their connection with osteoclasts is not yet fully understood. There is compelling evidence to suggest that age-related abnormalities such as epigenetic alterations, proteostasis network disruption, cellular senescence, and mitochondrial dysfunction, can stimulate osteoclast activity. This review intends to systematically discuss how aging hallmarks contribute to OA pathogenesis, placing particular emphasis on the age-induced shifts in osteoclast activity. It also aims to stimulate future studies probing into the pathological mechanisms and therapeutic approaches targeting osteoclasts in OA during aging.


Assuntos
Reabsorção Óssea , Cartilagem Articular , Osteoartrite , Humanos , Idoso , Osteoclastos/metabolismo , Qualidade de Vida , Osteoartrite/metabolismo , Reabsorção Óssea/metabolismo , Envelhecimento , Cartilagem Articular/metabolismo
20.
Heliyon ; 10(15): e35374, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39170388

RESUMO

Background: Increased osteoclast activity constitutes the primary etiology of excessive bone erosion in postmenopausal osteoporosis. ERp57, otherwise referred to as protein disulfide isomerase A3 (PDIA3), plays a crucial role in the regulation of intracellular calcium signaling. This is documented to exert a profound impact on osteoclast differentiation and functionality. Methods: To ascertain the potential role of ERp57 in disease progression, prevention, and treatment, network pharmacology and bioinformatics analyses were conducted in relation to postmenopausal osteoporosis and ERp57 inhibitor (Loc14). Then, subsequent experimental verifications were employed in vitro on osteoclast and osteoblast, and in vivo on ovariectomy (OVX) mice models. Results: Multiple enrichment analyses suggested that the "calcium signaling pathway" may constitute a potential avenue for therapeutic intervention by Loc14 in the treatment of postmenopausal osteoporosis. In vitro experiments demonstrated inhibition of ERp57 could block osteoclast differentiation and function by interfering with the expression of osteoclast marker genes (Traf6, Nfatc1, and Ctsk). Further mechanisms studies based on calcium imaging, qPCR, and WB established that ERp57 inhibitor (Loc14) could obstruct calcium oscillation in osteoclast precursor cells (OPCs) by limiting the entry sources of cytosolic Ca2+ and interfering with calmodulin/calcineurin/Nfatc1 pathway. Evidence from Micro-CT scanning and double calcein labeling confirmed that the application of Loc14 in vivo could alleviate bone loss and partially reversed the osteogenic impairment caused by OVX in mice. Conclusions: Our findings proved the suppressive effects of Loc14 on osteoclastogenesis via attenuating calcium oscillation and associated singling pathways, providing ERp57 as a potential therapeutic target for postmenopausal osteoporosis.

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