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1.
Glia ; 72(3): 504-528, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37904673

RESUMEN

Retinal degeneration, characterized by Müller cell gliosis and photoreceptor apoptosis, is considered an early event in diabetic retinopathy (DR). Our previous study proposed that GMFB may mediate diabetic retinal degeneration. This study identified GMFB as a sensitive and functional gliosis marker for DR. Compared to the wild type (WT) group, Gmfb knockout (KO) significantly improved visual function, attenuated gliosis, reduced the apoptosis of neurons, and decreased the mRNA levels of tumor necrosis factor α (Tnf-α) and interleukin-1ß (Il-1ß) in diabetic retinas. Tgf-ß3 was enriched by hub genes using RNA sequencing in primary WT and KO Müller cells. Gmfb KO significantly upregulated the transforming growth factor (TGF)-ß3 protein level via the AKT pathway. The protective effect of TGF-ß3 in the vitreous resulted in significantly improved visual function and decreased the number of apoptotic cells in the diabetic retina. The protection of Gmfb KO in primary Müller cells against high glucose (HG)-induced photoreceptor apoptosis was partially counteracted by TGF-ß3 antibody and administration of TGFBR1/2 inhibitors. Nuclear receptor subfamily 3 group C member 1 (NR3C1) binds to the promoter region of Gmfb and regulates Gmfb mRNA at the transcriptional level. NR3C1 was increased in the retinas of early diabetic rats but decreased in the retinas of late diabetic rats. N'-[(1E)-(3-Methoxyphenyl)Methylene]-3-Methyl-1H-Pyrazole-5-Carbohydrazide (DS-5) was identified as an inhibitor of GMFB, having a protective role in DR. We demonstrated that GMFB/AKT/TGF-ß3 mediated early diabetic retinal degeneration in diabetic rats. This study provides a novel therapeutic strategy for treating retinal degeneration in patients with DR.


Asunto(s)
Diabetes Mellitus Experimental , Retinopatía Diabética , Degeneración Retiniana , Humanos , Ratas , Animales , Degeneración Retiniana/patología , Células Ependimogliales/metabolismo , Estreptozocina/toxicidad , Proteínas Proto-Oncogénicas c-akt/metabolismo , Factor de Crecimiento Transformador beta3/efectos adversos , Factor de Crecimiento Transformador beta3/metabolismo , Diabetes Mellitus Experimental/inducido químicamente , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Gliosis/patología , Retina/metabolismo , Retinopatía Diabética/patología , ARN Mensajero/metabolismo
2.
Org Biomol Chem ; 21(22): 4540-4552, 2023 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-37212028

RESUMEN

Aggregation of amyloid-ß (Aß) peptides is characteristic of Alzheimer's disease (AD), which is the most common neurodegenerative disorder. Increasing evidence shows that Aß oligomers, the intermediates during aggregation, rather than the fully mature fibrils are the most toxic species of Aß and the key contributors to neurodegeneration. Aß oligomers have been considered as both biomarkers and drug targets for the diagnosis and treatment of AD. However, the high heterogeneity and metastability of oligomers make it difficult to determine their exact pathogenic mechanisms. Recent developments in Aß oligomer-targeting agents and techniques have provided great opportunities for overcoming the existing limitations. This review introduces the formation, structure, and toxicity of Aß oligomers and categorizes the Aß oligomer-targeting agents based on their chemical biological applications, including recognition and detection of Aß oligomers for diagnosis, intervention of Aß oligomerization for treatment, and stabilization of Aß oligomers for pathogenic studies. The design strategies and working mechanisms of the representative examples published in the past five years are highlighted. Finally, future development directions and challenges of Aß oligomer targeting are tentatively proposed.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Humanos , Péptidos beta-Amiloides/química , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/tratamiento farmacológico , Biología , Fragmentos de Péptidos/uso terapéutico
3.
Metab Brain Dis ; 38(2): 409-418, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35670992

RESUMEN

To investigate the effect of rapamycin on mitochondrial dynamic balance in diabetic rats subjected to cerebral ischemia-reperfusion injury. Male Sprague Dawley (SD) rats (n = 78) were treated with high fat diet combined with streptozotocin injection to construct diabetic model in rats. Transient middle cerebral artery occlusion (MCAO) of 2 hours was induced and the brains were harvested after 1 and 3 days of reperfusion. Rapamycin was injected intraperitoneally for 3 days prior to and immediately after operation, once a day. The neurological function was assessed, infarct volumes were measured and HE staining as well as immunohistochemistry were performed. The protein of hippocampus was extracted and Western blotting were performed to detect the levels of mTOR, mitochondrial dynamin related proteins (DRP1, p-DRP1, OPA1), SIRT3, and Nix/BNIP3L. Diabetic hyperglycemia worsened the neurological function performance (p < 0.01), enlarged infarct size (p < 0.01) and increased ischemic neuronal cell death (p < 0.01). The increased damage was associated with elevations of p-mTOR, p-S6, and p-DRP1; and suppressions of SIRT3 and Nix/BNIP3L. Rapamycin ameliorated diabetes-enhanced ischemic brain damage and reversed the biomarker alterations caused by diabetes. High glucose activated mTOR pathway and caused mitochondrial dynamics toward fission. The protective effect of rapamycin against diabetes-enhanced ischemic brain damage was associated with inhibiting mTOR pathway, redressing mitochondrial dynamic imbalance, and elevating SIRT3 and Nix/BNIP3L expression.


Asunto(s)
Lesiones Encefálicas , Isquemia Encefálica , Diabetes Mellitus Experimental , Daño por Reperfusión , Sirtuina 3 , Ratas , Masculino , Animales , Ratas Sprague-Dawley , Sirolimus/farmacología , Sirolimus/uso terapéutico , Dinámicas Mitocondriales , Diabetes Mellitus Experimental/metabolismo , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Sirtuina 3/metabolismo , Encéfalo/metabolismo , Lesiones Encefálicas/complicaciones , Isquemia Encefálica/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/complicaciones , Proteínas Reguladoras de la Apoptosis/metabolismo
4.
Exp Eye Res ; 223: 109207, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35926646

RESUMEN

Age-related macular degeneration (AMD) is one of the most common leading causes of irreversible blindness, and there is no effective treatment for it. It has been reported that aging is the greatest risk factor for AMD, and epithelial-mesenchymal transition (EMT) of retinal pigment epithelium (RPE) cells plays an important role in the pathogenesis of AMD. To clarify the relationship between senescence and EMT in RPE cells, we used the replicative senescence model, H2O2- and/or Nutlin3a-induced senescence model, and low-density and/or TGF-ß-induced EMT model to detect the expression of senescence-, RPE- and EMT-related genes, and assessed the motility of cells by using a scratch wound migration assay. The results showed that replicative senescence of RPE cells was accompanied by increased expression of EMT markers. However, senescent RPE cells themselves did not undergo EMT, as the H2O2and Nutlin3a treated cells showed no increase in EMT characteristics, including unchanged or decreased expression of EMT markers and decreased motility. Furthermore, conditioned medium (CM) from senescent cells induced EMT in presenescent RPE cells, and EMT accelerated the process of senescence. Importantly, dasatinib plus quercetin, which selectively eliminates senescent cells, inhibited low-density-induced EMT in RPE cells. These findings provide a better understanding of the interconnection between senescence and EMT in RPE cells. Removal of senescent cells by certain methods such as senolytics, might be a promising potential approach to prevent or delay the progression of RPE-EMT-related retinal diseases such as AMD.


Asunto(s)
Transición Epitelial-Mesenquimal , Degeneración Macular , Senescencia Celular , Medios de Cultivo Condicionados/farmacología , Dasatinib/farmacología , Células Epiteliales/metabolismo , Humanos , Peróxido de Hidrógeno/metabolismo , Degeneración Macular/metabolismo , Quercetina/farmacología , Epitelio Pigmentado de la Retina/metabolismo , Pigmentos Retinianos/metabolismo , Pigmentos Retinianos/farmacología , Factor de Crecimiento Transformador beta/metabolismo
5.
Diabetologia ; 64(1): 211-225, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33104828

RESUMEN

AIMS/HYPOTHESIS: Microglial activation in diabetic retinopathy and the protective effect of erythropoietin (EPO) have been extensively studied. However, the regulation of microglia in the retina and its relationship to inner blood-retinal barrier (iBRB) maintenance have not been fully characterised. In this study, we investigated the role of microglia in iBRB breakdown in diabetic retinopathy and the protective effects of EPO in this context. METHODS: Male Sprague Dawley rats were injected intraperitoneally with streptozotocin (STZ) to establish the experimental model of diabetes. At 2 h after STZ injection, the right and left eyes were injected intravitreally with EPO (16 mU/eye, 2 µl) and an equivalent volume of normal saline (NaCl 154 mmol/l), respectively. The rats were killed at 2 or 8 weeks after diabetes onset. Microglia activation was detected by ionised calcium binding adaptor molecule (IBA)-1 immunolabelling. Leakage of the iBRB was evaluated by albumin staining and FITC-dextran permeability assay. BV2 cells and primary rat microglia under hypoxic conditions were used to model microglial activation in diabetic retinopathy. Phagocytosis was examined by confocal microscopy in flat-mounted retina preparations and in microglia and endothelial cell cocultures. Protein levels of IBA-1, CD11b, complement component 1r (C1r), and Src/Akt/cofilin signalling pathway components were assessed by western blotting. RESULTS: In diabetic rat retinas, phagocytosis of endothelial cells by activated microglia was observed at 8 weeks, resulting in an increased number of acellular capillaries (increased by 426.5%) and albumin leakage. Under hypoxic conditions, activated microglia transmigrated to the opposite membrane of the transwell, where they disrupted the endothelial cell monolayer by engulfing endothelial cells. The activation and phagocytic activity of microglia was blocked by intravitreal injection of EPO. In vitro, IBA-1, CD11b and C1r protein levels were increased by 50.9%, 170.0% and 135.5%, respectively, by hypoxia, whereas the phosphorylated proteins of Src/Akt/cofilin signalling pathway components were decreased by 74.2%, 47.8% and 39.7%, respectively, compared with the control; EPO treatment abrogated these changes. CONCLUSIONS/INTERPRETATION: In experimental diabetic retinopathy, activated microglia penetrate the basement membrane of the iBRB and engulf endothelial cells, leading to iBRB breakdown. EPO exerts a protective effect that preserves iBRB integrity via activation of Src/Akt/cofilin signalling in microglia, as demonstrated in vitro. These data support a causal role for activated microglia in iBRB breakdown and highlight the therapeutic potential of EPO for the treatment of diabetic retinopathy. Graphical abstract.


Asunto(s)
Barrera Hematorretinal/efectos de los fármacos , Diabetes Mellitus Experimental/complicaciones , Retinopatía Diabética/fisiopatología , Eritropoyetina/administración & dosificación , Microglía/fisiología , Fagocitosis/efectos de los fármacos , Factores Despolimerizantes de la Actina/metabolismo , Animales , Barrera Hematorretinal/fisiopatología , Hipoxia de la Célula , Técnicas de Cocultivo , Células Endoteliales/metabolismo , Eritropoyetina/uso terapéutico , Humanos , Inyecciones Intravítreas , Masculino , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Familia-src Quinasas/metabolismo
6.
IUBMB Life ; 73(11): 1307-1324, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34405947

RESUMEN

Deep mining of the molecular mechanisms underlying diabetic retinopathy (DR) is critical for the development of novel therapeutic targets. This study aimed to identify key molecular signatures involved in experimental DR on the basis of integrated bioinformatics analysis. Four datasets consisting of 37 retinal samples were downloaded from the National Center of Biotechnology Information Gene Expression Omnibus. After batch-effect adjustment, bioinformatics tools such as Networkanalyst, Enrichr, STRING, and Metascape were used to evaluate the differentially expressed genes (DEGs), perform enrichment analysis, and construct protein-protein interaction networks. The hub genes were identified using Cytoscape software. The DEGs of interest from the meta-analysis were confirmed by quantitative reverse transcription-polymerase chain reaction in diabetic rats and a high-glucose-treated retinal cell model, respectively. A total of 743 DEGs related to lens differentiation, insulin resistance, and high-density lipoprotein (HDL) cholesterol metabolism were obtained using the meta-analysis. Alterations of dynamic gene expression in the chloride ion channel, retinol metabolism, and fatty acid metabolism were involved in the course of DR in rats. Importantly, H3K27m3 modifications regulated the expression of most DEGs at the early stage of DR. Using an integrated bioinformatics approach, novel molecular signatures were obtained for different stages of DR progression, and the findings may represent distinct therapeutic strategies for DR patients.


Asunto(s)
Retinopatía Diabética/genética , Retinopatía Diabética/patología , Regulación de la Expresión Génica , Mapas de Interacción de Proteínas/genética , Animales , Línea Celular , Bases de Datos Factuales , Diabetes Mellitus Experimental/genética , Células Ependimogliales/efectos de los fármacos , Células Ependimogliales/patología , Perfilación de la Expresión Génica/métodos , Glucosa/farmacología , Histonas/genética , Histonas/metabolismo , Masculino , Ratas Sprague-Dawley
7.
Exp Eye Res ; 204: 108448, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33484702

RESUMEN

Photoreceptor (PR) dysfunction or death is the key pathological change in retinal degeneration (RD). The death of PRs might be due to a primary change in PRs themselves or secondary to the dysfunction of the retinal pigment epithelium (RPE). Poly(ADP-ribose) polymerase (PARP) was reported to be involved in primary PR death, but whether it plays a role in PR death secondary to RPE dysfunction has not been determined. To clarify this question and develop a new therapeutic approach, we studied the changes in PAR/PARP in the RCS rat, a RD model, and tested the effect of PARP intervention when given alone or in combination with RPE cell transplantation. The results showed that poly(ADP-ribosyl)ation of proteins was increased in PRs undergoing secondary death in RCS rats, and this result was confirmed by the observation of similar changes in sodium iodate (SI)-induced secondary RD in SD rats. The increase in PAR/PARP was highly associated with increased apoptotic PRs and decreased visual function, as represented by lowered b-wave amplitudes on electroretinogram (ERG). Then, as we expected, when the RCS rats were treated with subretinal injection of the PARP inhibitor PJ34, the RD process was delayed. Furthermore, when PJ34 was given simultaneously with subretinal ARPE-19 cell transplantation, the therapeutic effects were significantly improved and lasted longer than those of ARPE-19 or PJ34 treatment alone. These results provide a potential new approach for treating RD.


Asunto(s)
Modelos Animales de Enfermedad , Fenantrenos/farmacología , Células Fotorreceptoras de Vertebrados/efectos de los fármacos , Poli Adenosina Difosfato Ribosa/antagonistas & inhibidores , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Degeneración Retiniana/terapia , Epitelio Pigmentado de la Retina/trasplante , Animales , Western Blotting , Supervivencia Celular/fisiología , Trasplante de Células , Células Cultivadas , Electrorretinografía , Etiquetado Corte-Fin in Situ , Células Fotorreceptoras de Vertebrados/fisiología , Poli(ADP-Ribosa) Polimerasas/metabolismo , Ratas , Ratas Mutantes , Reacción en Cadena en Tiempo Real de la Polimerasa , Degeneración Retiniana/metabolismo , Degeneración Retiniana/fisiopatología
8.
Exp Eye Res ; 188: 107791, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31491426

RESUMEN

MicroRNAs (miRNAs) have been shown to play critical roles in the pathogenesis and progression of degenerative retinal diseases like age-related macular degeneration (AMD). In this study, we first demonstrated that miR-24 plays an important role in maintaining retinal structure and visual function of rats by targeting chitinase-3-like protein 1 (CHI3L1). In the retinal pigment epithelial (RPE) cells of Royal College of Surgeons (RCS) rats, an animal model of genetic retinal degeneration (RD), miR-24 was found lower and CHI3L1 level was higher in comparison with those in Sprague-Dawley (SD) rats. Other changes in the eyes of RCS rats include activated AKT/mTOR and ERK pathways and abnormal autophagy in the RPE cells. Such roles of miR-24 and CHI3L1 were further confirmed in RCS rats by subretinal injection of agomiR-24, which decreased CHI3L1 level and preserved retinal structure and function. Upstream, NF-κB was identified as the regulator of miR-24 in the RPE cells of these rats. On the other hand, in SD rats, intraocular treatment of antagomiR-24 induced pathological changes similar to those in RCS rats. The results revealed the protective roles for miR-24 to RPE cells and a mechanism for RD in RCS rats was proposed: extracellular stress stimuli first activate the NF-κB signaling pathway, which lowers miR-24 expression so that CHI3L1 increased. CHI3L1 sequentially results in aberrant autophagy and RPE dysfunction by activating AKT/mTOR and ERK pathways. Taken together, although the possibility, that the therapeutic effects in RCS rats are caused by other transcriptional changes regulated by miR-24, cannot be excluded, these findings indicate that miR-24 protects rat retina by targeting CHI3L1. Thus, miR-24 and CHI3L1 might be the targets for developing more effective therapy for degenerative retinal diseases like AMD.


Asunto(s)
Proteína 1 Similar a Quitinasa-3/metabolismo , MicroARNs/fisiología , Retina/metabolismo , Degeneración Retiniana/prevención & control , Epitelio Pigmentado de la Retina/metabolismo , Animales , Autofagia , Western Blotting , Línea Celular , Modelos Animales de Enfermedad , Regulación hacia Abajo , Electrorretinografía , Etiquetado Corte-Fin in Situ , Masculino , Microscopía Electrónica de Transmisión , Ratas , Ratas Mutantes , Ratas Sprague-Dawley , Retina/fisiopatología , Degeneración Retiniana/enzimología , Degeneración Retiniana/fisiopatología , Epitelio Pigmentado de la Retina/fisiopatología , Transducción de Señal
9.
Exp Eye Res ; 188: 107726, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31319082

RESUMEN

Retinitis pigmentosa (RP) is a group of genetically heterogeneous retinal diseases with more than 80 identified causative genes to date. Mutations in the RHO (rhodopsin, OMIM, 180380) are the most common cause of autosomal dominant RP (adRP) worldwide. RHO is also one of the few RP genes that can cause autosomal recessive RP (arRP). To explore the frequency of RP mutations in Chinese populations, panel-based NGS (next-generation sequencing) screening and Sanger sequencing validation were performed for RP patients from 72 unrelated Chinese families. Here we reported the identified mutations only in the RHO gene. Our results showed that 4 mutations in RHO were detected in 5 (6.94%) of the 72 RP families, including two known missense mutations, c.158C > G (p.P53R) and c.551A > C (p.Q184P), and two novel mutations, c.34delC (p.P12NA) and c.82C > T (p.Q28X). The c.34delC (p.P12NA) mutation was detected in heterozygous state in one patient with intermediate RP phenotype. The c.82C > T (p.Q28X) mutation was found in a homozygous state in one proband with advanced RP phenotype at the age of 32. Clinical examination of the heterozygous carriers of c.82C > T (p.Q28X) in that family showed that the father at the age of 60s experienced no symptoms of RP and normal fundus examinations but displayed reduced electroretinography (ERG) and abnormal visual field. The sister and brother at the age of 30s showed no typical aspects of RP phenotypes. Our results not only expand the mutation spectrum of the RHO gene, but also suggest that the 2 null mutations might play minor dominant effects, leading to less severe and slower retinal degeneration in heterozygous state and more severe phenotype in homozygous state.


Asunto(s)
Pueblo Asiatico/genética , Mutación , Retinitis Pigmentosa/genética , Rodopsina/genética , Adulto , China/epidemiología , Codón sin Sentido , Análisis Mutacional de ADN , Electrorretinografía , Femenino , Mutación del Sistema de Lectura , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Microscopía Fluorescente , Persona de Mediana Edad , Mutación Missense , Linaje , Retina/fisiopatología , Retinitis Pigmentosa/diagnóstico , Retinitis Pigmentosa/fisiopatología , Trastornos de la Visión/fisiopatología , Campos Visuales/fisiología , Adulto Joven
10.
Clin Exp Ophthalmol ; 47(9): 1182-1197, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31483932

RESUMEN

PURPOSE: To explore the mechanisms of erythropoietin (EPO) in maintaining outer blood-retinal barrier (BRB) in diabetic rats. METHODS: Sprague-Dawley rats were rendered diabetic with intraperitoneal injection of streptozotocin, and then followed by intravitreal injection of EPO. Two and four weeks later, the permeability of outer BRB was examined with FITC-dextran leakage assay, following a method to demarcate the inner and outer retina based on retinal blood supply. The glyoxal-treated ARPE-19 cells, incubated with EPO, soluble EPO receptor (sEPOR), Gö6976, or digoxin, were studied for cell viability and barrier function. The expressions of ZO-1, occludin, VEGFR2, HIF-1α, MAPKs, and AKT were examined with Western blot and immunofluorescence. RESULTS: The major Leakage of FITC-dextran was detected in the outer nuclear layer in both 2- and 4-week diabetic rats. The leakage was largely ameliorated in EPO-treated diabetic rats. The protein expressions of ZO-1 and occludin in the RPE-Bruch's membrane choriocapillaris complex were significantly decreased, whereas HIF-1α and JNK pathways were activated, in 4-week diabetic rats. These changes were prevented by EPO treatment. The in vitro study with ARPE-19 cells confirmed these changes, and the protective effect of EPO was abolished by sEPOR. Gö6976 and digoxin rescued the tight junction and barrier function in glyoxal-treated ARPE-19 cells. CONCLUSIONS: In early diabetic rats, the outer BRB might be more severely damaged and its breakdown is the major factor for retinal oedema. EPO maintains the outer BRB integrity through down-regulation of HIF-1α and JNK signallings, and thus up-regulating ZO-1 and occludin expressions in RPE cells.


Asunto(s)
Barrera Hematorretinal/efectos de los fármacos , Retinopatía Diabética/tratamiento farmacológico , Eritropoyetina/administración & dosificación , Ocludina/metabolismo , Vasos Retinianos/fisiopatología , Regulación hacia Arriba , Proteína de la Zonula Occludens-1/metabolismo , Animales , Western Blotting , Diabetes Mellitus Experimental , Retinopatía Diabética/metabolismo , Retinopatía Diabética/fisiopatología , Inyecciones Intravítreas , Masculino , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/administración & dosificación , Vasos Retinianos/efectos de los fármacos
11.
Exp Eye Res ; 168: 89-99, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29196060

RESUMEN

miRs play critical roles in oxidative stress-related retinopathy pathogenesis. miR-365 was identified in a previously constructed library from glyoxal-treated rat Müller cell. This report explores epigenetic alterations in Müller cells under oxidative stress to develop a novel therapeutic strategy. To examine the miR-365 expression pattern, in situ hybridization and quantitative RT-PCR were performed. Bioinformatical analysis and dual luciferase report assay were applied to identify and confirm target genes. Streptozotocin (STZ)-treated rats were used as the diabetic retinopathy (DR) model. Lentivirus-mediated anti-miR-365 was delivered subretinally and intravitreally into the rats' eyes. The functional and structural changes were evaluated by electroretinogram (ERG), histologically, and through examination of expression levels of metallopeptidase inhibitor 3 (Timp3), glial fibrillary acidic protein (Gfap), recoverin (Rcvrn) and vascular endothelia growth factor A (Vegfa). Oxidative stress factors and pro-inflammatory cytokines were analyzed. miR-365 expression was confirmed in the glyoxal-treated rat Müller cell line (glyoxal-treated rMC-1). In the retina, miR-365 mainly localized in the inner nuclear layer (INL). The increased miR-365 participated in Müller cell gliosis through oxidative stress aggravation, as observed in glyoxal-treated rMC-1 and DR rats before 6 weeks. Timp3 was a target and negatively regulated by miR-365. When miR-365 was inhibited, Timp3 expression was upregulated, Müller cell gliosis was alleviated, and retinal oxidative stress was attenuated. Visual function was also partially rescued as detected by ERG. miR-365 was found to be highly expressed in the retina and the abnormality of miR-365/Timp3 pathway is closely related to the pathology, like Müller gliosis, and the visual injury in DR. The mechanism might be through oxidative stress, and miR-365/Timp3 could be a potential therapeutic target for treating DR.


Asunto(s)
Diabetes Mellitus Experimental/fisiopatología , Retinopatía Diabética/fisiopatología , MicroARNs/fisiología , Estrés Oxidativo/fisiología , Retina/metabolismo , Inhibidor Tisular de Metaloproteinasa-3/metabolismo , Análisis de Varianza , Animales , Far-Western Blotting , Células Cultivadas , Electrorretinografía , Células Ependimogliales/metabolismo , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo
12.
Exp Eye Res ; 177: 160-172, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30096326

RESUMEN

The pathological change of retinal pigment epithelial (RPE) cells is one of the main reasons for the development of age-related macular degeneration (AMD). Thus, cultured RPE cells are a proper cell model for studying the etiology of AMD in vitro. However, such cultured RPE cells easily undergo epithelial-mesenchymal transition (EMT) that results in changes of cellular morphology and functions of the cells. To restore and maintain the mesenchymal-epithelial transition (MET) of the cultured RPE cells, we cultivated dedifferentiated porcine RPE (pRPE) cells and compared their behaviors in four conditions: 1) in cell culture dishes with DMEM/F12 containing FBS (CC dish-FBS), 2) in petri dishes with DMEM/F12 containing FBS (Petri dish-FBS), 3) in cell culture dishes with DMEM/F12 containing N2 and B27 supplements (CC dish-N2B27), and 4) in petri dishes with DMEM/F12 containing N2 and B27 (Petri dish-N2B27). In addition to observing the cell morphology and behavior, RPE specific markers, as well as EMT-related genes and proteins, were examined by immunostaining, quantitative real-time PCR and Western blotting. The results showed that dedifferentiated pRPE cells maintained EMT in CC dish-FBS, Petri dish-FBS and CC dish-N2B27 groups, whereas MET was induced when the dedifferentiated pRPE cells were cultured in Petri dish-N2B27. Such induced pRPE cells showed polygonal morphology with increased expression of RPE-specific markers and decreased EMT-associated markers. Similar results were observed in induced pluripotent stem cell-derived RPE cells. Furthermore, during the re-differentiation of those dedifferentiated pRPE cells, Petri dish-N2B27 reduced the activity of RhoA and induced F-actin rearrangement, which promoted the nuclear exclusion of transcriptional co-activator with PDZ-binding motif (TAZ) and TAZ target molecule zinc finger E-box binding protein (ZEB1), both of which are EMT inducing factors. This study provides a simple and reliable method to reverse dedifferentiated phenotype of pRPE cells into epithelialized phenotype, which is more appropriate for studying AMD in vitro, and suggests that MET of other cell types might be induced by a similar approach.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Transición Epitelial-Mesenquimal/fisiología , Epitelio Pigmentado de la Retina/citología , Animales , Biomarcadores/metabolismo , Western Blotting , Desdiferenciación Celular/fisiología , Células Cultivadas , Células Epiteliales/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Reacción en Cadena de la Polimerasa , Epitelio Pigmentado de la Retina/metabolismo , Porcinos
13.
Cell Biol Int ; 42(7): 877-889, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29512223

RESUMEN

Macrophages play critical roles in wound healing process. They switch from "classically activated" (M1) phenotype in the early inflammatory phase to "alternatively activated" (M2) phenotype in the later healing phase. However, the dynamic process of macrophage phenotype switching in diabetic wounds burdened with bacteria is unclear. In this report, Pseudomonas aeruginosa, frequently detected in diabetic foot ulcers, was inoculated into cutaneous wounds of db/db diabetic mice to mimic bacterium-infected diabetic wound healing. We observed that P. aeruginosa infection impaired diabetic wound healing and quickly promoted the expression of pro-inflammatory genes (M1 macrophage markers) tumor necrosis factor-α (tnf-α), interleukin-1ß (il-1ß) and il-6 in wounds. The expression of markers of M2 macrophages, including il-10, arginase-1, and ym1 were also upregulated. In addition, similar gene expression patterns were observed in macrophages isolated directly from wounds. Immunostaining showed that P. aeruginosa infection increased both the ratios of M1 and M2 macrophages in wounds compared with that in control groups, which was further confirmed by in vitro culturing macrophages with P. aeruginosa and skin fibroblast conditioned medium. However, the ratios of the expression levels of pro-inflammatory genes to anti-inflammatory gene il-10 was increased markedly in P. aeruginosa infected wounds and macrophages compared with that in control groups, and P. aeruginosa prolonged the presence of M1 macrophages in the wounds. These data demonstrated that P. aeruginosa in diabetic wounds activates a mixed M1/M2 macrophage phenotype with an excessive activation of M1 phenotype or relatively inadequate activation of M2 phenotype.


Asunto(s)
Macrófagos/microbiología , Fenotipo , Infecciones por Pseudomonas/microbiología , Cicatrización de Heridas/fisiología , Animales , Biomarcadores/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/microbiología , Expresión Génica/fisiología , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
14.
Artículo en Inglés | MEDLINE | ID: mdl-39288041

RESUMEN

Iterative learning model predictive control (ILMPC) has become an excellent data-driven intelligent control strategy for digitized batch manufacturing, featured by the progressive improvement of tracking performance along trials, and the persistent rejection of stochastic disturbance along time. The point-to-point learning mechanism of existing ILMPC generally relies on identical operating conditions along trials to guarantee the integrity and accuracy of historical data. However, the variations of production requirements usually lead to trial-varying operating references and durations, resulting in incomplete and inaccurate historical information for the iterative learning of subsequent trials. To promote the adaptability and flexibility of ILMPCs with unconformable prior information, a data-driven self-modification scheme is originally embedded into ILMPC in this article to transfer the prior knowledge contained in the historical operating data into the form consistent with the condition of each current trial. The control actions are imitated along trials by an adaptive deep neural network (DNN), which is then utilized to generate reference control signals for iterative learning in each trial. For attenuating the influence of the considerable DNN approximation error in early trials with limited data accumulation, the 2-D optimization of ILMPC is performed under a tube control frame to ensure the time-domain bounded stability. Based on the intrinsic recursive feasibility and the guaranteed time-domain stability, the iteration-domain bounded convergence of the developed ILMPC system is theoretically validated. Simulations on the nonlinear injection molding process verify the superiority of the proposed method in adapting to significant changes in operating reference and duration.

15.
IEEE Trans Cybern ; 54(5): 2746-2756, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38133984

RESUMEN

Few-shot fault diagnosis is a challenging problem for complex engineering systems due to the shortage of enough annotated failure samples. This problem is increased by varying working conditions that are commonly encountered in real-world systems. Meta-learning is a promising strategy to solve this point, open issues remain unresolved in practical applications, such as domain adaptation, domain generalization, etc. This article attempts to improve domain adaptation and generalization by focusing on the distribution-shift robustness of meta-learning from the task generation perspective. In fact, few-shot fault diagnosis under varying working conditions allows to address the distribution shift problem in a natural way. An unsupervised across-tasks meta-learning strategy with distributional similarity preference is proposed, where the core is the distribution-distance-weighting mechanism. Differently from the naive random meta-train task generation strategy used in existing meta-learning methods, the source instances that present a more similar distribution with respect to the target instances gain larger weightings in the task generation. This strategy leads to a meta-task training set that is enough diverse, and at the same time can be easily learned due to the distribution similarity features of the source tasks. The proposed method introduces the concept of maximum mean discrepancy that is applied to derive the distribution distance of the measurements. Moreover, a model-agnostic meta-learning is applied to realize few-shot fault diagnosis under varying working conditions. The proposed solutions are verified and compared by considering two public datasets used for bearing fault diagnosis. The results show that the proposed strategy outperforms different related few-shot fault diagnosis methods under varying working conditions. Moreover, it is thus proved that, meta-learning with distribution similarity feature represents an effective approach for domain adaptation and generalization.

16.
Adv Sci (Weinh) ; 11(6): e2305315, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38081795

RESUMEN

The service life of large battery packs can be significantly influenced by only one or two abnormal cells with faster aging rates. However, the early-stage identification of lifetime abnormality is challenging due to the low abnormal rate and imperceptible initial performance deviations. This work proposes a lifetime abnormality detection method for batteries based on few-shot learning and using only the first-cycle aging data. Verified with the largest known dataset with 215 commercial lithium-ion batteries, the method can identify all abnormal batteries, with a false alarm rate of only 3.8%. It is also found that any capacity and resistance-based approach can easily fail to screen out a large proportion of the abnormal batteries, which should be given enough attention. This work highlights the opportunities to diagnose lifetime abnormalities via "big data" analysis, without requiring additional experimental effort or battery sensors, thereby leading to extended battery life, increased cost-benefit, and improved environmental friendliness.

17.
Dalton Trans ; 53(36): 14966-14970, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39189405

RESUMEN

We herein report a "Fight Aggregation with Aggregation" (FAA) approach for redirection of amyloid-ß peptide (Aß) aggregation using a europium(III) complex (EuL3) that can undergo H-aggregation in aqueous solution under physiological conditions. The H-aggregates of EuL3 may serve as scaffolds that can facilitate the accumulation of Aß to form non-fibrillar co-assemblies. As a result, the Aß aggregation-induced cytotoxicity was inhibited.


Asunto(s)
Péptidos beta-Amiloides , Complejos de Coordinación , Europio , Agregado de Proteínas , Europio/química , Europio/farmacología , Péptidos beta-Amiloides/metabolismo , Péptidos beta-Amiloides/química , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Complejos de Coordinación/síntesis química , Agregado de Proteínas/efectos de los fármacos , Humanos , Supervivencia Celular/efectos de los fármacos , Animales
18.
Chem Commun (Camb) ; 60(11): 1440-1443, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38206371

RESUMEN

A terbium(III) complex-based time-resolved luminescence probe for selenocysteine can inhibit selenoprotein activity via a selenolate-triggered cleavage reaction of sulfonamide bonds in living cells.


Asunto(s)
Selenocisteína , Terbio , Terbio/química , Luminiscencia , Selenoproteínas
19.
Front Nutr ; 11: 1381779, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38595789

RESUMEN

Background: To identify key and shared insulin resistance (IR) molecular signatures across all insulin-sensitive tissues (ISTs), and their potential targeted drugs. Methods: Three datasets from Gene Expression Omnibus (GEO) were acquired, in which the ISTs (fat, muscle, and liver) were from the same individual with obese mice. Integrated bioinformatics analysis was performed to obtain the differentially expressed genes (DEGs). Weighted gene co-expression network analysis (WGCNA) was carried out to determine the "most significant trait-related genes" (MSTRGs). Enrichment analysis and PPI network were performed to find common features and novel hub genes in ISTs. The shared genes of DEGs and genes between DEGs and MSTRGs across four ISTs were identified as key IR therapeutic target. The Attie Lab diabetes database and obese rats were used to verify candidate genes. A medical drug-gene interaction network was conducted by using the Comparative Toxicogenomics Database (CTD) to find potential targeted drugs. The candidate drug was validated in Hepa1-6 cells. Results: Lipid metabolic process, mitochondrion, and oxidoreductase activity as common features were enriched from ISTs under an obese context. Thirteen shared genes (Ubd, Lbp, Hp, Arntl, Cfd, Npas2, Thrsp., Tpx2, Pkp1, Sftpd, Mthfd2, Tnfaip2, and Vnn3) of DEGs across ISTs were obtained and confirmed. Among them, Ubd was the only shared gene between DEGs and MSTRGs across four ISTs. The expression of Ubd was significantly upregulated across four ISTs in obese rats, especially in the liver. The IR Hepa1-6 cell models treated with dexamethasone (Dex), palmitic acid (PA), and 2-deoxy-D-ribose (dRib) had elevated expression of Ubd. Knockdown of Ubd increased the level of p-Akt. A lowing Ubd expression drug, promethazine (PMZ) from CTD analysis rescued the decreased p-Akt level in IR Hepa1-6 cells. Conclusion: This study revealed Ubd, a novel and shared IR molecular signature across four ISTs, as an effective biomarker and provided new insight into the mechanisms of IR. PMZ was a candidate drug for IR which increased p-Akt level and thus improved IR by targeting Ubd and downregulation of Ubd expression. Both Ubd and PMZ merit further clinical translational investigation to improve IR.

20.
Invest Ophthalmol Vis Sci ; 65(11): 1, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39226050

RESUMEN

Purpose: This study aimed to explore the impact of HSPA13 on epithelial-mesenchymal transition (EMT) in retinal pigment epithelial (RPE) cells and proliferative vitreoretinopathy (PVR) development, along with its associated molecular mechanisms. Methods: HSPA13 expression was evaluated in epiretinal membranes (ERMs) from patients with PVR using immunohistochemistry. The effects of HSPA13 knockdown on TGFß1-induced EMT in hESC-RPE cells were studied through quantitative PCR (qPCR), Western blot, and wound healing assays. Intracellular Ca2+ levels were measured using Fluo-8/AM incubation. A rat PVR model was induced by the intravitreal injection of RPE cells combined with platelet-rich plasma (PRP). RNA-seq was applied to study the molecular mechanism of HSPA13 knockdown-mediated EMT inhibition. Results: HSPA13 was found in human ERMs and its expression increased with TGFß1 treatment in hESC-RPE cells. Knockdown of HSPA13 inhibited TGFß1-induced EMT and migration. In the PVR rat model, HSPA13 was expressed in the ERMs and its knockdown in RPE cells reduced the development of PVR. Consistent with these observations, RNA-seq showed a global suppression of TGFß1-induced EMT and migration by shHSPA13 in RPE cells. Mechanistically, TGFß1 treatment increased intracellular Ca2+ levels, leading to an upregulation of HSPA13 expression. Downregulation of HSPA13 hindered the phosphorylation of PI3K/Akt in TGFß1-induced RPE cells. Conclusions: Our study revealed the involvement of HSPA13 in PVR development, as well as in TGFß1-induced EMT of RPE through the PI3K/Akt signaling pathway. Targeting HSPA13-related pathways involved in regulating EMT in RPE cells could serve as a novel therapeutic approach for patients with PVR.


Asunto(s)
Modelos Animales de Enfermedad , Transición Epitelial-Mesenquimal , Proteínas HSP70 de Choque Térmico , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Epitelio Pigmentado de la Retina , Transducción de Señal , Factor de Crecimiento Transformador beta1 , Epitelio Pigmentado de la Retina/metabolismo , Epitelio Pigmentado de la Retina/patología , Animales , Factor de Crecimiento Transformador beta1/metabolismo , Humanos , Ratas , Proteínas HSP70 de Choque Térmico/metabolismo , Proteínas HSP70 de Choque Térmico/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Vitreorretinopatía Proliferativa/genética , Vitreorretinopatía Proliferativa/patología , Vitreorretinopatía Proliferativa/metabolismo , Masculino , Western Blotting , Células Cultivadas , Ratas Sprague-Dawley , Movimiento Celular , Inmunohistoquímica
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