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1.
Artigo em Inglês | MEDLINE | ID: mdl-38833147

RESUMO

PURPOSE: The objective of the study is to test the efficacy of cyclopentenyl cytosine (CPEC)-coated stents on blocking artery stenosis, promoting reendothelialization, and reducing thrombosis. METHODS: Scanning electron microscopy was employed to observe the morphological characteristics of stents coated with a mixture of CPEC and poly(lactic-co-glycolic acid) (PLGA) copolymer. PLGA has been used in various Food and Drug Administration (FDA)-approved therapeutic devices. In vitro release of CPEC was tested to measure the dynamic drug elution. Comparison between CPEC- and everolimus-coated stents on neointimal formation and thrombosis formation was conducted after being implanted into the human internal mammary artery and grafted to the mouse aorta. RESULTS: Optimization in stent coating resulted in uniform and consistent coating with minimal variation. In vitro drug release tests demonstrated a gradual and progressive discharge of CPEC. CPEC- or everolimus-coated stents caused much less stenosis than bare-metal stents. However, CPEC stent-implanted arteries exhibited enhanced reendothelialization compared to everolimus stents. Mechanistically, CPEC-coated stents reduced the proliferation of vascular smooth muscle cells while simultaneously promoting reendothelialization. More significantly, unlike everolimus-coated stents, CPEC-coated stents showed a significant reduction in thrombosis formation even in the absence of ongoing anticoagulant treatment. CONCLUSIONS: The study establishes CPEC-coated stent as a promising new device for cardiovascular interventions. By enhancing reendothelialization and preventing thrombosis, CPEC offers advantages over conventional approaches, including the elimination of the need for anti-clogging drugs, which pave the way for improved therapeutic outcomes and management of atherosclerosis-related medical procedures.

2.
bioRxiv ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38617336

RESUMO

Formation of biomolecular condensates can be driven by weak multivalent interactions and emergent polymerization. However, the mechanism of polymerization-mediated condensate formation is less studied. We found lateral root cap cell (LRC)-specific SUPPRESSOR OF RPS4-RLD1 (SRFR1) condensates fine-tune primary root development. Polymerization of the SRFR1 N-terminal domain is required for both LRC condensate formation and optimal root growth. Surprisingly, the first intrinsically disordered region (IDR1) of SRFR1 can be functionally substituted by a specific group of intrinsically disordered proteins known as dehydrins. This finding facilitated the identification of functional segments in the IDR1 of SRFR1, a generalizable strategy to decode unknown IDRs. With this functional information we further improved root growth by modifying the SRFR1 condensation module, providing a strategy to improve plant growth and resilience.

3.
Adv Mater ; 35(8): e2204996, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36515124

RESUMO

Nanomachines with active propulsion have emerged as an intelligent platform for targeted cancer therapy. Achieving an efficient locomotion performance using an external energy conversion is a key requirement in the design of nanomachines. In this study, inspired by diverse spiky structures in nature, a photomagnetically powered nanomachine (PMN) with a spiky surface and thermally dependent viscosity tunability is proposed to facilitate mechanical motion in lysosomes for cancer mechanotherapy. The hybrid nanomachine is integrated with magnetic nanoparticles as the core and covered with gold nanotips. Physical simulations and experimental results prove that the spiky structure endows nanomachines with an obvious photomagnetic coupling effect in the NIR-II region through the alignment and orienting movement of plasmons on the gold tips. Using a coupling-enhanced magnetic field, PMNs are efficiently assembled into chain-like structures to further elevate energy conversion efficiency. Notably, PMNs with the thermal control of viscosity are efficiently propelled under simultaneously applied dual external energy sources in cell lysosomes. Enhanced mechanical destruction of cancer cells via PMNs is confirmed both in vitro and in vivo under photomagnetic treatment. This study provides a new direction for designing integrated nanomachines with active adaptability to physiological environments for cancer treatment.


Assuntos
Neoplasias , Humanos , Viscosidade , Ouro/química , Movimento (Física)
4.
Biochim Biophys Acta Mol Basis Dis ; 1868(9): 166447, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35643386

RESUMO

AIMS: Thoracic aortic aneurysm/dissection (TAAD) is a life-threatening disease with diverse clinical manifestations. Although the association between methamphetamine (METH) and TAAD is frequently observed, the causal relationship between METH abuse and aortic aneurysm/dissection has not been established. This study was designed to determine if METH causes aortic aneurysm/dissection and delineate the underlying mechanism. METHODS AND RESULTS: A new TAAD model was developed by exposing METH to SD rats pre-treated with lysyl oxidase inhibitor ß-aminopropionitrile (BAPN). Combination of METH and BAPN caused thoracic aortic aneurysm/dissection in 60% of rats. BAPN+METH significantly increased the expression and activities of both matrix metalloproteinase MMP2 and MMP9, consistent with the severe elastin breakage and dissection. Mechanistically, METH increased CCAAT-enhancer binding protein ß (C/EBPß) expression by enhancing mothers against decapentaplegic homolog 3 (Smad3) and extracellular regulated protein kinase (ERK1/2) signaling. METH also promoted C/EBPß binding to MMP2 and MMP9 promoters. Blocking C/EBPß significantly attenuated METH+BAPN-induced TAAD and MMP2/MMP9 expression. Moreover, BAPN+METH promoted aortic medial smooth muscle cell (SMC) apoptosis through C/EBPß-mediated IGFBP5/p53/PUMA signaling pathways. More importantly, the expression of C/EBPß, MMP2/MMP9, and apoptosis-promoting proteins was increased in the aorta of human patients with thoracic aortic dissection, suggesting that the mechanisms identified in animal study could be relevant to human disease. CONCLUSIONS: Our study demonstrated that METH exposure has a casual effect on TAAD. C/EBPß mediates METH-introduced TAAD formation by causing elastin breakage, medial cell loss and degeneration. Therefore, C/EBPß may be a potential factor for TAAD clinical diagnosis or treatment.


Assuntos
Aneurisma da Aorta Torácica , Dissecção Aórtica , Metanfetamina , Aminopropionitrilo , Dissecção Aórtica/induzido quimicamente , Dissecção Aórtica/metabolismo , Animais , Aneurisma da Aorta Torácica/induzido quimicamente , Aneurisma da Aorta Torácica/metabolismo , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Elastina , Humanos , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Ratos , Ratos Sprague-Dawley
5.
FASEB J ; 35(3): e21381, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33617091

RESUMO

Renal interstitial fibrosis (RIF) is a pathological process that fibrotic components are excessively deposited in the renal interstitial space due to kidney injury, resulting in impaired renal function and chronic kidney disease. The molecular mechanisms controlling renal fibrosis are not fully understood. In this present study, we identified Nuclear protein 1 (Nupr1), a transcription factor also called p8, as a novel regulator promoting renal fibrosis. Unilateral ureteral obstruction (UUO) time-dependently induced Nupr1 mRNA and protein expression in mouse kidneys while causing renal damage and fibrosis. Nupr1 deficiency (Nupr1-/- ) attenuated the renal tubule dilatation, tubular epithelial cell atrophy, and interstitial collagen accumulation caused by UUO. Consistently, Nupr1-/- significantly decreased the expression of type I collagen, myofibroblast markers smooth muscle α-actin (α-SMA), fibroblast-specific protein 1 (FSP-1), and vimentin in mouse kidney that were upregulated by UUO. These results suggest that Nupr1 protein was essential for fibroblast activation and/or epithelial-mesenchymal transition (EMT) during renal fibrogenesis. Indeed, Nupr1 was indispensable for TGF-ß-induced myofibroblast activation of kidney interstitial NRK-49F fibroblasts, multipotent mesenchymal C3H10T1/2 cells, and the EMT of kidney epithelial NRK-52E cells. It appears that Nupr1 mediated TGF-ß-induced α-SMA expression and collagen synthesis by initiating Smad3 signaling pathway. Importantly, trifluoperazine (TFP), a Nupr1 inhibitor, alleviated UUO-induced renal fibrosis. Taken together, our results demonstrate that Nupr1 promotes renal fibrosis by activating myofibroblast transformation from both fibroblasts and tubular epithelial cells.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Transição Epitelial-Mesenquimal , Fibroblastos/fisiologia , Rim/patologia , Proteínas de Neoplasias/fisiologia , Animais , Células Cultivadas , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Fibrose , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miofibroblastos/fisiologia , Ratos , Transdução de Sinais/fisiologia , Proteína Smad3/fisiologia , Fatores de Transcrição da Família Snail/fisiologia , Trifluoperazina/farmacologia
6.
Int J Biol Macromol ; 161: 810-817, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32553949

RESUMO

Phragmites rhizoma (PR) is comprised of polysaccharides as its main active component. Currently, there are few studies on polysaccharides from PR, especially in purification and structure. In this study, an acidic polysaccharide (PRP-2) was obtained from PR by ultrasonic assisted extraction and secondary column chromatography purification (Diethylaminoethyl cellulose-52 (DEAE-52) and Sephadex G-100). Its structural characteristics were investigated by the gel permeation chromatography (GPC), gas chromatography and mass spectrometry (GC-MS), infrared spectroscopy (IR) and nuclear magnetic resonance (NMR) spectroscopy. The results showed that PRP-2 possessed the molecular weight of 20,332 Da and contained total sugars (71.73%), uronic acids (7.51%), proteins (0.57%) and sulfate radical (9.38%). The polysaccharide was composed of Galactose (34.70%), Fucose (36.15%) and a small amount of Rhamnose (0.88%) with a molar ratio of 39.50: 41.15: 1.00. It consisted of three sugar residues, →3)-ß-D-GalpA-(1→, →2, 3)-α-L-Fucp-(1→ and α-L-Fucp (4SO3-) -(1→. PRP-2 could protect RAW246.7 macrophages from the cytotoxic effect induced by lipopolysaccharide (LPS), inhibit the LPS-induced NO production in RAW246.7 macrophages, which displayed its anti-inflammatory activity. Therefore, PRP-2 has the potential to be used as a functional component.


Assuntos
Anti-Inflamatórios/farmacologia , Poaceae/química , Polissacarídeos/farmacologia , Rizoma/química , Animais , Linhagem Celular , Cromatografia em Gel/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectroscopia de Ressonância Magnética/métodos , Camundongos , Células RAW 264.7 , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
7.
Food Funct ; 11(5): 4625-4637, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32400829

RESUMO

The purpose of this study was to investigate whether Gelidium pacificum Okamura polysaccharides (sulfated polysaccharide, GPOP-1) had beneficial effects on mice with antibiotic-associated diarrhea (AAD). Compared with the natural recovery group, GPOP-1 increased the richness and diversity of the gut microbiome, as well as altered the composition of the gut microbiota. At the genus level, GPOP-1 significantly increased the relative abundance of Bacteroides, Oscillospira, and Bifidobacterium and decreased the relative abundance of Parabacteroides, Sutterella, and AF12. The metabolic pathway differences according to the Kyoto Encyclopedia of Genes and Genomes (KEGG) revealed that the metabolic function of the gut microbiota could be significantly improved by GPOP-1. Furthermore, GPOP-1 downregulated the concentrations of inflammatory cytokines, tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) and interleukin-2 (IL-2), alleviated the pathological features of the cecum, and increased the contents of acetates, propionates, butyrates, and total short-chain fatty acids (SCFAs). Results indicated that GPOP-1 had beneficial effects on mice with AAD by promoting the recovery of the gut microbiota and mucosal barrier function, reversing metabolic disorders, downregulating the levels of inflammatory cytokines and improving the content of SCFAs.


Assuntos
Diarreia/prevenção & controle , Polissacarídeos/uso terapêutico , Alga Marinha , Animais , Antibacterianos/efeitos adversos , Ceco/metabolismo , Diarreia/induzido quimicamente , Modelos Animais de Doenças , Microbioma Gastrointestinal/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fitoterapia , Polissacarídeos/administração & dosagem , Polissacarídeos/farmacologia , Distribuição Aleatória
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