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1.
Nat Commun ; 14(1): 5067, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37604806

RESUMO

Dexterous locomotion, such as immediate direction change during fast movement or shape reconfiguration to perform diverse tasks, are essential animal survival strategies which have not been achieved in existing soft robots. Here, we present a kind of small-scale dexterous soft robot, consisting of an active dielectric elastomer artificial muscle and reconfigurable chiral-lattice foot, that enables immediate and reversible forward, backward and circular direction changes during fast movement under single voltage input. Our electric-driven soft robot with the structural design can be combined with smart materials to realize multimodal functions via shape reconfigurations under the external stimulus. We experimentally demonstrate that our dexterous soft robots can reach arbitrary points in a plane, form complex trajectories, or lower the height to pass through a narrow tunnel. The proposed structural design and shape reconfigurability may pave the way for next-generation autonomous soft robots with dexterous locomotion.

2.
Contrast Media Mol Imaging ; 2022: 5383146, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35909588

RESUMO

The abnormal proliferation, migration, and epithelial-mesenchymal transformation (EMT) of lens epithelial cells (LECs) are the main reasons for vision loss caused by posterior capsular opacification (PCO) after cataract surgery. Insulin-like growth factor-1 (IGF-1) was found to be associated with the pathogenesis of cataracts, but its biological role in PCO is poorly understood. In the present study, IGF-1 overexpression facilitated the proliferation, migration, and EMT, whereas knockdown of IGF-1 markedly suppressed the proliferation, migration, and TGF-ß2-induced EMT of LECs. Additionally, to evaluate valuable microRNAs (miRNAs) which target IGF-1 to modulate LEC-EMT, we predicted miR-3666 might regulate IGF-1 by binding its 3'UTR according to the bioinformatics database. Furthermore, we verified that miR-3666 directly targeted IGF-1 by luciferase reporter assay. By using miR-3666 mimics, cell proliferation, migration, and invasion were suppressed, while being enhanced by the reduction of miR-3666. Knockout of IGF1 reverses the effect of the miR-3666 inhibitor on the malignant behavior of LECs. These results indicate the role of miR-3666/IGF-1 in LEC-EMT that offers new strategies for the therapy and prevention of PCO.


Assuntos
Opacificação da Cápsula , Fator de Crescimento Insulin-Like I , Cristalino , MicroRNAs , Opacificação da Cápsula/genética , Opacificação da Cápsula/metabolismo , Opacificação da Cápsula/patologia , Movimento Celular/genética , Proliferação de Células , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal/genética , Transição Epitelial-Mesenquimal/fisiologia , Humanos , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Cristalino/metabolismo , Cristalino/patologia , MicroRNAs/genética , MicroRNAs/metabolismo
3.
Autophagy ; 18(4): 765-782, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34403298

RESUMO

Thiel-Behnke corneal dystrophy (TBCD) is an epithelial-stromal TGFBI dystrophy caused by mutations in the TGFBI (transforming growth factor beta induced) gene, though the underlying mechanisms and pathogenesis of TBCD are still obscure. The study identifies a novel mutation in the TGFBI gene (p.Gly623_His626del) in a TBCD pedigree. Characteristics of the typical vacuole formation, irregular corneal epithelial thickening and thinning, deposition of eosinophilic substances beneath the epithelium, and involvement of the anterior stroma were observed in this pedigree via transmission electron microscopy (TEM) and histological staining. Tgfbi-p.Gly623_Tyr626del mouse models of TBCD were subsequently generated via CRISPR/Cas9 technology, and the above characteristics were further verified via TEM and histological staining. Lysosomal dysfunction and downregulation of differential expression protein CTSD (cathepsin D) were observed using LysoTracker Green DND-26 and proteomic analysis, respectively. Hence, lysosomal dysfunction probably leads to autophagic flux obstruction in TBCD; this was supported by enhanced LC3-II and SQSTM1 levels and decreased CTSD. TFEB (transcription factor EB) was prominently decreased in TBCD corneal fibroblasts and administration of ATP-competitive MTOR inhibitor torin 1 reversed this decline, resulting in the degradation of accumulated mut-TGFBI (mutant TGFBI protein) via the ameliorative lysosomal function and autophagic flux owing to elevated TFEB activity as measured by western blot, confocal microscopy, and flow cytometry. Transfected HEK 293 cells overexpressing human full-length WT-TGFBI and mut-TGFBI were generated to further verify the results obtained in human corneal fibroblasts. Amelioration of lysosome dysfunction may therefore have therapeutic efficacy in the treatment of TBCD.Abbreviations AS-OCT: anterior segment optical coherence tomography; ATP: adenosine triphosphate; Cas9: CRISPR-associated protein 9; CLEAR: coordinated lysosomal expression and regulation; CRISPR: clustered regularly interspaced short palindromic repeats; CTSB: cathepsin B; CTSD: cathepsin D; CTSF: cathepsin F; CTSL: cathepsin L; DNA: deoxyribonucleic acid; ECM: extracellular matrix; Fas1: fasciclin 1; FC: flow cytometry; GAPDH: glyceraldeyde-3-phosphate dehydrogenase; GCD2: granular corneal dystrophy type 2; HE: hematoxylin and eosin; LAMP2: lysosomal-associated membrane protein; MT: mutation type; MTOR: mechanistic target of rapamycin kinase; MTORC1: MTOR complex 1; mut-TGFBI: mutant TGFBI protein; SD: standard deviation; TBCD: Thiel-Behnke corneal dystrophy; TEM: transmission electron microscopy; TFEB: transcription factor EB; TGFBI: transforming growth factor beta induced; WT: wild type.


Assuntos
Catepsina D , Distrofias Hereditárias da Córnea , Trifosfato de Adenosina/metabolismo , Animais , Autofagia/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Proteínas Sanguíneas , Catepsina D/metabolismo , Distrofias Hereditárias da Córnea/genética , Distrofias Hereditárias da Córnea/metabolismo , Distrofias Hereditárias da Córnea/patologia , Células HEK293 , Humanos , Lisossomos/metabolismo , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Mutantes/metabolismo , Proteômica , Serina-Treonina Quinases TOR/metabolismo , Fator de Crescimento Transformador beta/metabolismo
4.
Mol Med ; 26(1): 124, 2020 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-33297931

RESUMO

BACKGROUND: Age-related cataract (ARC) is a serious visual impairment disease, and its pathogenesis is unclear. This article aims to investigate the role of ROCK1 in the apoptosis of lens epithelial cells (LECs) in age-related cataracts. METHODS: We collect anterior capsule samples from normal people, patients with age-related cataracts, young mice and naturally aging cataract mice. The oxidative stress-induced apoptosis model was constructed by cultivating HLE-B3 cells with H2O2. MTT, Hoechst 33342, and TUNEL assay were performed to explore proliferation and apoptosis. HE assay was used to observe cell morphology. The gene and protein expression were assessed by quantitative real-time PCR, western blot, immunofluorescence, and immunohistochemical staining. RESULT: The results from the clinic and mice experiments showed that the numbers of lens epithelial cells from cataract individuals were less than the control individuals. In vitro, the apoptotic cells were increased in lens epithelial cells under H2O2 treatment. The ROCK1 protein level increased in the lens epithelial cells from age-related cataract patients and the old mice, respectively. Meanwhile, the up-regulation of the ROCK1 gene was associated with H2O2-induced HLE-B3 cells apoptosis. MTT and apoptosis assay showed ROCK1 was necessary in mediating H2O2-induced lens epithelial cells apoptosis through ROCK1 over-expression and knockdown experiment, respectively. Further investigation showed that p53 protein levels had been increased during ROCK1-mediated apoptosis in response to H2O2. Besides, ROCK1 phosphorylated p53 at ser15 to up-regulate its protein level. CONCLUSIONS: This study established the novel association of ROCK1/p53 signaling with lens epithelial cells apoptosis and age-related cataract genesis.


Assuntos
Apoptose/genética , Catarata/etiologia , Células Epiteliais/metabolismo , Proteína Supressora de Tumor p53/genética , Quinases Associadas a rho/genética , Animais , Apoptose/efeitos dos fármacos , Catarata/metabolismo , Catarata/patologia , Linhagem Celular , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/farmacologia , Imuno-Histoquímica , Camundongos , Fosforilação , Proteína Supressora de Tumor p53/metabolismo , Quinases Associadas a rho/metabolismo
5.
Cell Death Discov ; 6(1): 85, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32983576

RESUMO

Macular corneal dystrophy (MCD) is ascribed to mutations in the carbohydrate sulfotransferase (CHST6) gene affecting keratan sulfate (KS) hydrophilicity and causing non-sulfated KS to precipitate in keratocytes and the corneal stroma. We investigated roles for inflammatory responses in MCD pathogenesis by examining the lysosomal-autophagy pathway and activation of pyroptosis in MCD keratocytes. Normal and lesioned keratocytes were obtained from MCD patients undergoing corneal transplantation. The keratocytes were subjected to gene sequencing, RT-PCR, western blotting, transmission electron microscopy, histological staining, induction and inhibition assays of autophagy and pyroptosis, CCK-8 and LysoTracker Green DND-26 labeling, and flow cytometry. A novel homozygous MCD mutation was identified in a family from Northeast China; the mutation was distinguished by cytoplasmic vacuolation, cell membrane disruption, electron dense deposits, and deposition of a band of Periodic acid-Schiff and Alcian blue-positive material in the keratocytes and stroma layer. KS protein levels were decreased, expression of p62 and LC3-II proteins was enhanced, cathepsin D expression was declined and the LysoTracker Green DND-26 signal was dramatically reduced in MCD keratocytes. Bafilomycin-A1 treatment significantly increased caspase-1 and Pro-IL-1ß expression in normal and MCD keratocytes. Nod-like receptors pyrins-3 (NLRP3), caspase-1, Pro-IL-1ß, and IL-1ß levels were pronouncedly elevated in cells exposed to H2O2. Ac-YVAD-CMK treatment reversed this expression in normal and MCD keratocytes. Suppression of the autophagic degradation of non-sulfated KS by impaired autophagic flux in MCD keratocytes triggers pyroptosis. Amelioration of impaired autophagy and restraint of pyroptosis may, therefore, have therapeutic efficacy in the treatment of MCD.

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