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1.
J Med Genet ; 61(10): 973-981, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39153854

RESUMEN

BACKGROUND: Variants in the RPGR are the leading cause of X-linked retinopathies (XLRPs). Further in-depth investigation is needed to understand the natural history. METHODS: Review of all case records, molecular genetic testing results, best-corrected visual acuity (BCVA), retinal imaging data (including fundus autofluorescence imaging and optical coherence tomography (OCT)), static visual field (VF) assessments and full-field electroretinogram. RESULTS: Genetic testing was conducted on 104 male patients from 89 family pedigrees, identifying 22 novel variants and 1 de novo variant. The initial symptoms appeared in 78.2% of patients at a median age of 5 years. BCVA declined at a mean rate of 0.02 (IQR, 0-0.04) logarithm of the minimum angle of resolution per year, with a gradual, non-linear decrease over the first 40 years. Autofluorescence imaging revealed macular atrophy at a median age of 36.1 (IQR, 29.9-43.2) years. Patients experienced blindness at a median age of 42.5 (IQR, 32.9-45.2) years according to WHO visual impairment categories. OCT analysis showed a mean ellipsoid zone narrowing rate of 23.3 (IQR, -1.04-22.29) µm/month, with an accelerated reduction in the first 40 years (p<0.01). The median age at which ERG no longer detected a waveform was 26.5 (IQR, 20.5-32.8) years. Comparison by variant location indicated faster progression in patients with exon 1-14 variants during the initial two decades, while those with ORF15 variants showed accelerated progression from the third decade. CONCLUSIONS: We provide a foundation for determining the treatment window and an objective basis for evaluating the therapeutic efficacy of gene therapy for XLRP.


Asunto(s)
Proteínas del Ojo , Linaje , Tomografía de Coherencia Óptica , Humanos , Masculino , Proteínas del Ojo/genética , Adulto , China/epidemiología , Persona de Mediana Edad , Ceguera/genética , Niño , Adolescente , Electrorretinografía , Preescolar , Enfermedades Genéticas Ligadas al Cromosoma X/genética , Enfermedades Genéticas Ligadas al Cromosoma X/patología , Enfermedades Genéticas Ligadas al Cromosoma X/epidemiología , Agudeza Visual , Adulto Joven , Mutación , Estudios de Cohortes , Femenino
2.
J Transl Med ; 22(1): 447, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38741132

RESUMEN

BACKGROUND: Retinal ischemia/reperfusion (RIR) is implicated in various forms of optic neuropathies, yet effective treatments are lacking. RIR leads to the death of retinal ganglion cells (RGCs) and subsequent vision loss, posing detrimental effects on both physical and mental health. Apigenin (API), derived from a wide range of sources, has been reported to exert protective effects against ischemia/reperfusion injuries in various organs, such as the brain, kidney, myocardium, and liver. In this study, we investigated the protective effect of API and its underlying mechanisms on RGC degeneration induced by retinal ischemia/reperfusion (RIR). METHODS: An in vivo model was induced by anterior chamber perfusion following intravitreal injection of API one day prior to the procedure. Meanwhile, an in vitro model was established through 1% oxygen and glucose deprivation. The neuroprotective effects of API were evaluated using H&E staining, spectral-domain optical coherence tomography (SD-OCT), Fluoro-Gold retrograde labeling, and Photopic negative response (PhNR). Furthermore, transmission electron microscopy (TEM) was employed to observe mitochondrial crista morphology and integrity. To elucidate the underlying mechanisms of API, the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, flow cytometry assay, western blot, cell counting kit-8 (CCK-8) assay, lactate dehydrogenase (LDH) assay, JC-1 kit assay, dichlorofluorescein-diacetate (DCFH-DA) assay, as well as TMRE and Mito-tracker staining were conducted. RESULTS: API treatment protected retinal inner plexiform layer (IPL) and ganglion cell complex (GCC), and improved the function of retinal ganglion cells (RGCs). Additionally, API reduced RGC apoptosis and decreased lactate dehydrogenase (LDH) release by upregulating Bcl-2 and Bcl-xL expression, while downregulating Bax and cleaved caspase-3 expression. Furthermore, API increased mitochondrial membrane potential (MMP) and decreased extracellular reactive oxygen species (ROS) production. These effects were achieved by enhancing mitochondrial function, restoring mitochondrial cristae morphology and integrity, and regulating the expression of OPA1, MFN2, and DRP1, thereby regulating mitochondrial dynamics involving fusion and fission. CONCLUSION: API protects RGCs against RIR injury by modulating mitochondrial dynamics, promoting mitochondrial fusion and fission.


Asunto(s)
Apigenina , Dinámicas Mitocondriales , Fármacos Neuroprotectores , Daño por Reperfusión , Células Ganglionares de la Retina , Células Ganglionares de la Retina/efectos de los fármacos , Células Ganglionares de la Retina/patología , Células Ganglionares de la Retina/metabolismo , Apigenina/farmacología , Apigenina/uso terapéutico , Animales , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/patología , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Dinámicas Mitocondriales/efectos de los fármacos , Masculino , Apoptosis/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Modelos Biológicos , Ratones Endogámicos C57BL
3.
J Org Chem ; 89(5): 3111-3122, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38343173

RESUMEN

We herein present a study on the Ag(I)-mediated semipinacol rearrangement of iododifluorohomoallyl alcohols, the resulting allylic difluoromethyl ketones underwent oxidative allylic C-H esterification under palladium catalysis in the absence of external ligand. This process yielded a range of difluoromethyl ketones derived from allyl esters in a single operation. The reaction features broad scope of o-nitrobenzoic acids and homoallylic iododifluoroalcohols affording the targeted molecules in synthetically useful yields. Control experiments illustrated that the silver salt acted as not only a Lewis acid to promote the cleavage of a C-I bond and furnish the semipinacol rearrangement but also a co-oxidant in the catalytic cycle for the allylic C-H esterification.

4.
Nucleic Acids Res ; 50(14): e81, 2022 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-35536244

RESUMEN

Interpretation of non-coding genome remains an unsolved challenge in human genetics due to impracticality of exhaustively annotating biochemically active elements in all conditions. Deep learning based computational approaches emerge recently to help interpret non-coding regions. Here, we present LOGO (Language of Genome), a self-attention based contextualized pre-trained language model containing only two self-attention layers with 1 million parameters as a substantially light architecture that applies self-supervision techniques to learn bidirectional representations of the unlabelled human reference genome. LOGO is then fine-tuned for sequence labelling task, and further extended to variant prioritization task via a special input encoding scheme of alternative alleles followed by adding a convolutional module. Experiments show that LOGO achieves 15% absolute improvement for promoter identification and up to 4.5% absolute improvement for enhancer-promoter interaction prediction. LOGO exhibits state-of-the-art multi-task predictive power on thousands of chromatin features with only 3% parameterization benchmarking against the fully supervised model, DeepSEA and 1% parameterization against a recent BERT-based DNA language model. For allelic-effect prediction, locality introduced by one dimensional convolution shows improved sensitivity and specificity for prioritizing non-coding variants associated with human diseases. In addition, we apply LOGO to interpret type 2 diabetes (T2D) GWAS signals and infer underlying regulatory mechanisms. We make a conceptual analogy between natural language and human genome and demonstrate LOGO is an accurate, fast, scalable, and robust framework to interpret non-coding regions for global sequence labeling as well as for variant prioritization at base-resolution.


Asunto(s)
Diabetes Mellitus Tipo 2 , Genoma Humano , Humanos , Regiones Promotoras Genéticas , Secuencias Reguladoras de Ácidos Nucleicos , Análisis de Secuencia de ADN/métodos
5.
Proc Natl Acad Sci U S A ; 118(40)2021 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-34599099

RESUMEN

Alternative splicing of G protein-coupled receptors has been observed, but their functions are largely unknown. Here, we report that a splice variant (SV1) of the human growth hormone-releasing hormone receptor (GHRHR) is capable of transducing biased signal. Differing only at the receptor N terminus, GHRHR predominantly activates Gs while SV1 selectively couples to ß-arrestins. Based on the cryogenic electron microscopy structures of SV1 in the apo state or GHRH-bound state in complex with the Gs protein, molecular dynamics simulations reveal that the N termini of GHRHR and SV1 differentiate the downstream signaling pathways, Gs versus ß-arrestins. As suggested by mutagenesis and functional studies, it appears that GHRH-elicited signal bias toward ß-arrestin recruitment is constitutively mediated by SV1. The level of SV1 expression in prostate cancer cells is also positively correlated with ERK1/2 phosphorylation but negatively correlated with cAMP response. Our findings imply that constitutive signal bias may be a mechanism that ensures cancer cell proliferation.


Asunto(s)
Empalme Alternativo/genética , Variación Genética/genética , Receptores de Neuropéptido/genética , Receptores de Hormona Reguladora de Hormona Hipofisaria/genética , Animales , Línea Celular Tumoral , Proliferación Celular/genética , Células Cultivadas , Células HEK293 , Humanos , Sistema de Señalización de MAP Quinasas/genética , Células PC-3 , Células Sf9 , Transducción de Señal/genética , beta-Arrestinas/genética
6.
J Sci Food Agric ; 104(10): 6139-6148, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38442084

RESUMEN

BACKGROUND: Roasting is an important process in the formation of coffee flavor characteristics, which determines the quality of coffee and consumer acceptance. However, the influence of roasting degree on the flavor characteristics of cold brew coffee has not been fully described. RESULTS: In the present study, the flavor characteristics of cold brew coffee with different roasting degrees were compared in detail by using chromatographic and electronic sensory approaches, and the flavor changes induced by freeze-drying were investigated. Pyrazine and heterocyclic compounds were the main aroma compounds in coffee, and gradually dominated with the increase of roasting. Pyridine was consistently present in cold brew coffees of different roasting degrees and showed significant gradient of quantity accumulation. Aroma compounds such as pyrazine, linalool and furfuryl acetate were the main contributors to coffee roasting, floral and fruity flavor. Freeze-drying preserved the fruity and floral aromas of medium-roasted cold brew coffee, whereas reducing the bitterness, astringency and acidity properties that are off-putting to consumers. CONCLUSION: The higher consumer acceptance and enjoyment in medium roast cold brew coffee may be related to its stronger floral and fruity aroma. The aroma profile qualities of freeze-drying processed medium roasted cold brewed coffee were more dominant and more suitable for freeze-drying processing than medium dark roasting. Application of freeze-drying for cold brew coffee will promote the convenience of drinking. The present study provides valuable technical guidance in improving the flavor and quality of cold brew coffee, and also promotes its commercialization process. © 2024 Society of Chemical Industry.


Asunto(s)
Coffea , Café , Nariz Electrónica , Aromatizantes , Liofilización , Cromatografía de Gases y Espectrometría de Masas , Odorantes , Gusto , Odorantes/análisis , Humanos , Coffea/química , Café/química , Aromatizantes/química , Aromatizantes/análisis , Compuestos Orgánicos Volátiles/análisis , Compuestos Orgánicos Volátiles/química , Lengua/química , Culinaria/métodos , Manipulación de Alimentos/métodos , Calor , Semillas/química , Masculino , Femenino , Adulto
7.
J Sci Food Agric ; 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39189594

RESUMEN

BACKGROUND: Synchronous degradation between anthocyanin and vitamin C was found in fruit and vegetable juice matrices. To investigate whether the C-ring of anthocyanin is the key site of this interaction, cyanidin with four different C-ring modifications (3-glucosylation, 3,5-diglucosylation, 6″-malonylation, pyranylation) was added to vitamin C-containing apple juice, and the changes of anthocyanin retention, vitamin C retention, color, antioxidative activity and differential metabolites were analyzed. RESULTS: The anthocyanin retention was in the order of pyranylation >6″-malonylation >3,5-diglucosylation >3-glucosylation. The vitamin C retention was in the order of 6″-malonylation > pyranylation >3,5-diglucosylation >3-glucosylation. The order of color stability was the same as that of anthocyanin retention, and the order of antioxidative activity was opposite to that of vitamin C retention. The results showed that modification at the C-ring limited the activity of anthocyanin, and suggested that the C-ring was one of the key sites for anthocyanin and vitamin C interaction. The shared differential metabolite of all apple juice matrices added with different anthocyanins was trans-hinokiresinol, which was likely generated from anthocyanin skeleton reacted with certain compounds in apple juice. CONCLUSION: This study showed that modification of the anthocyanin C-ring could affect the anthocyanin and vitamin C interaction to some extent, which provided valuable insights for the application of anthocyanin C-ring modification in shelf-life quality control of typical fruit and vegetable beverages with the coexistence of anthocyanin and vitamin C. © 2024 Society of Chemical Industry.

8.
J Sci Food Agric ; 104(6): 3532-3542, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38146066

RESUMEN

BACKGROUND: Flavor is considered as a key quality attribute of fruit juice affecting consumer acceptance. During processing, the flavor loss of cloudy juice always occurs due to the variations of juice cloud particles. Pectin, a major component of cloud particles, plays an important role in cloud stability. In this work, we focused on the effects of variation of three pectin fractions caused by gentle centrifugation and clarification on the physicochemical properties, volatile content and sensory profile of heat-sterilized muskmelon cloudy juice. RESULTS: Centrifugation treatment reduced the total soluble solids and viscosity of cloudy juice and increased cloud stability. With centrifugation increased, the contents of most monosaccharides in the three pectin fractions were reduced. Most aroma-active aldehydes and alcohols, such as (2E,6Z)-nonadienal, 1-octen-3-ol and (E)-non-2-enal, after gentle centrifugation and clarification, were maintained, but most esters were decreased. The volatile compositions were highly related to the three pectin fractions. The addition of chelator-soluble pectin and sodium carbonate-soluble pectin could decrease the formation of dimethyl trisulfide and dimethyl disulfide in clarified juice, thereby improving the sensory profile. CONCLUSION: The results suggested that endogenous chelator-soluble pectin and sodium carbonate-soluble pectin can be used in heat-sterilized fruit juice to improve flavor quality, with an emphasis on a significant reduction in volatile sulfur compounds. © 2023 Society of Chemical Industry.


Asunto(s)
Carbonatos , Calor , Pectinas , Pectinas/análisis , Frutas/química , Quelantes
9.
Crit Rev Food Sci Nutr ; 63(28): 9409-9424, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35486571

RESUMEN

Anthocyanins are widely distributed in nature and exhibit brilliant colors and multiple health-promoting effects; therefore, they are extensively incorporated into foods, pharmaceuticals, and cosmetic industries. Anthocyanins have been traditionally produced by plant extraction, which is characterized by high expenditure, low production rates, and rather complex processes, and hence cannot meet the increasing market demand. In addition, the emerging environmental issues resulting from traditional solvent extraction technologies necessitate a more efficient and eco-friendly alternative strategy for producing anthocyanins. This review summarizes the efficient approach for green extraction and introduces a novel strategy for microbial biosynthesis of anthocyanins, emphasizing the technological changes in production.


Asunto(s)
Antocianinas , Plantas , Extractos Vegetales
10.
J Biochem Mol Toxicol ; 37(4): e23303, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36639873

RESUMEN

Persistent poly (ADP-ribose) polymerase 1 (PARP-1) activation has proven detrimental and can lead to PARP-1-dependent cell death. Mitochondria-associated endoplasmic reticulum (ER) membranes (MAMs) serve as essential hubs for many biological pathways, such as autophagy and mitochondria fission and fusion. This study aimed to alleviate the effects of hydrogen peroxide (H2 O2 )-induced persistent PARP-1 activation and MAM dysregulation by the usage of a PARP-1 inhibitor. Results showed that receptor-interacting protein kinase (RIPK) 1 inhibitor (necrostatin-1) and PARP-1 inhibitor (olaparib) protected retinal precursor cells from H2 O2 -induced death, while a pan-caspase inhibitor (Z-VAD-FMK) failed to protect R28 cells. Olaparib also alleviated H2 O2 -induced MAM dysregulation, as evidenced by decreased VDAC1/ITPR3 interactions and reduced mitochondrial membrane potential collapse. Additionally, olaparib also inhibited H2 O2 -induced autophagy. Inhibiting autophagic flux increased MAM signaling under both normal and oxidative conditions. Furthermore, H2 O2 treatment caused a reduction in the protein level of mitofusin-2 (MFN2) in a dose- and time-dependent manner. Mfn2 knockdown was found to further magnify MAM dysregulation and mitochondrial dysfunction under normal and oxidative conditions. Mfn2 overexpression surprisingly enhanced H2 O2 -induced MAM signaling and failed to rescue H2 O2 -induced mitochondrial dysfunction. These results indicate that MAMs probably serve as a membrane source for oxidative stress-associated autophagy. MAM dysregulation also contributed to H2 O2 -induced PARP-1-dependent cell death. However, more studies are required to decipher the link between the modulation of Mfn2 expression, changes in MAM integrity, and alterations in mitochondrial performances.


Asunto(s)
Parthanatos , Retículo Endoplásmico/metabolismo , Estrés del Retículo Endoplásmico , Mitocondrias/metabolismo , Estrés Oxidativo , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Muerte Celular
11.
Retina ; 43(4): 659-669, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36729610

RESUMEN

PURPOSE: To determine the prognostic value of outer retinal tubulation (ORT) in the eyes of a Chinese cohort with Bietti crystalline dystrophy (BCD). METHODS: This retrospective, multicenter cohort study enrolled 42 patients with clinically and genetically diagnosed BCD. Eighty eyes with good-quality images of spectral domain optical coherence tomography were included. Demographic details and clinical data were collected. The characteristics of ORT, including prevalence, location, and morphologic characteristics were analyzed. RESULTS: Forty-two patients with BCD harbored potentially CYP4V2 disease-causing mutations. The mutation spectrum comprised 17 unique variants, 9 of which were novel. Fifty-two of these 80 eyes demonstrated evidence of ORT. The incidence of ORT is significantly higher in Stage 2 than other stages ( P < 0.001). ORT was mainly bilateral and located at the margin of the atrophic area of retinal pigment epithelium (RPE), and dynamically changed with the progressive RPE atrophy. The process of RPE atrophy was slower in eyes with ORT ( P = 0.017), with significantly longer intact RPE width in Stage 3 ( P = 0.024). Eyes with ORT had slower vision loss than eyes without ORT ( P = 0.044). CONCLUSION: ORT may be a sign of the onset of RPE atrophy in early-stage BCD and may suggest less risk of rapid progression in late-stage BCD.


Asunto(s)
Degeneración Retiniana , Enfermedades de la Retina , Humanos , Epitelio Pigmentado de la Retina/patología , Estudios Retrospectivos , Estudios de Cohortes , Enfermedades de la Retina/diagnóstico , Enfermedades de la Retina/genética , Enfermedades de la Retina/patología , Degeneración Retiniana/patología , Tomografía de Coherencia Óptica , Atrofia/patología
12.
BMC Ophthalmol ; 23(1): 100, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36918830

RESUMEN

BACKGROUND: The study aims to investigate the relationship between the volume-accumulated reflectivity (termed "integral") on spectral domain optical coherence tomography (SD-OCT) and cone density on adaptive optics (AO) imaging. METHODS: In this cross-sectional study, both eyes of 32 healthy subjects and 5 patients with inherited retinal diseases (IRD) were studied. The parameter, integral, was defined as the volume-accumulated reflectivity values in a selected region on OCT images; integrals of the ellipsoid zone (EZ) and interdigitation zone (IZ) were measured at 2°, 3°, 4°, 5°and 6° eccentricity along the four meridians on fovea-centered OCT B-scans. Cone density in the same region was measured using a flood illumination adaptive optics camera RTX1. RESULTS: Integrals of EZ, IZ and cone density shared similar distribution patterns. Integral of the IZ was better correlated with cone density in both healthy people (r = 0.968, p < 0.001) and those with IRD (r = 0.823, p < 0.001) than direct measurements of reflectivity on OCT images. A strong correlation was found between best corrected visual acuity (BCVA) and cone density at 2° eccentricity (r = -0.857, p = 0.002). BCVA was also correlated with the integral of the IZ at the foveola (r = -0.746, p = 0.013) and fovea (r = -0.822, p = 0.004). CONCLUSIONS: The new parameter "integral" of the photoreceptor outer segment measured from SD-OCT was noted to correlate with cone density and visual function in this pilot study.


Asunto(s)
Células Fotorreceptoras Retinianas Conos , Enfermedades de la Retina , Tomografía de Coherencia Óptica , Humanos , Recuento de Células , Estudios Transversales , Proyectos Piloto , Retina , Tomografía de Coherencia Óptica/métodos
13.
Compr Rev Food Sci Food Saf ; 22(6): 4871-4889, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37755237

RESUMEN

The impact of sugary foods on public health has contributed to the development of low-sugar and sugar-substituted products, and sugar reduction has become a major challenge for the food industry. There is growing empirical evidence that odor can enhance the perception of sweetness without increasing the caloric load. This current review summarizes the researches on odor-induced sweetness enhancement published in recent years and discusses the mechanisms and influencing factors of odor-sweetness interactions. In addition, by combing existing studies, this paper also summarizes the research methods and strategies to investigate odor-induced sweetness enhancement. Finally, the feasibility of synergistic enhancement of sweetness through the superposition of odor with other senses (texture, visual, etc.) is also discussed and analyzed. In conclusion, odor-induced sweetness enhancement may present an alternative or complementary approach for developing foods with less sugar.


Asunto(s)
Odorantes , Gusto , Edulcorantes/análisis , Azúcares
14.
J Cell Mol Med ; 26(23): 5858-5871, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36349481

RESUMEN

As the main loading-bearing tissue of eye, sclera exerts an important role in the pathophysiology of glaucoma. Intraocular pressure (IOP) generates mechanical strain on sclera. Recent studies have demonstrated that sclera, especially the peripapillary sclera, undergoes complicated remodelling under the mechanical strain. However, the mechanisms of the hypertensive scleral remodelling in human eyes remained uncertain. In this study, peripapillary human scleral fibroblasts (ppHSFs) were applied cyclic mechanical strain by Flexcell-5000™ tension system. We found that CXC- ligands and CXCR2 were differentially expressed after strain. Increased cell proliferation and inhibited cell motility were observed when CXCR2 was upregulated under the strain, whereas cell proliferation and motility did not have a significant change when CXCR2 was knocked down. CXCR2 could facilitate cell proliferation ability, modulate the mRNA and protein expressions of type I collagen and matrix metalloproteinase 2 via JAK1/2-STAT3 signalling pathway. In addition, CXCR2 might inhibit cell migration via FAK/MLC2 pathway. Taken together, CXCR2 regulated protein production and affected cell behaviours of ppHSFs. It might be a potential therapeutic target for the hypertensive scleral remodelling.


Asunto(s)
Fibroblastos , Glaucoma , Receptores de Interleucina-8B , Esclerótica , Humanos , Matriz Extracelular , Fibroblastos/metabolismo , Glaucoma/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Esclerótica/citología , Receptores de Interleucina-8B/genética , Receptores de Interleucina-8B/metabolismo , Movimiento Celular , Estrés Mecánico , Células Cultivadas
15.
Lab Invest ; 102(11): 1225-1235, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35804043

RESUMEN

Glaucoma, a common cause of blindness, is characterized by the progressive loss of retinal ganglion cells (RGCs). Growing evidence suggests that nobiletin (NOB) is a promising neuroprotective drug; however, its effects on glaucomatous neurodegeneration remain unknown. Using rat models of microbead occlusion in vivo and primary RGCs model of hypoxia in vitro, we first demonstrate that NOB reduces RGC apoptosis by a TUNEL assay, Hoechst 33342 staining and FluoroGold (FG) retrograde labeling. This effect does not depend on intraocular pressure (IOP) lowering. Additionally, NOB partially restored the functional and structural damage of inner retinas, attenuated Müller glial activation and oxidative stress caused by ocular hypertension. At 2 weeks after IOP elevation, NOB further enhanced Nrf2/HO-1 pathway in RGCs to withstand the cumulative damage of ocular hypertension. With the administration of HO-1 inhibitor tin-protoporphyrin IX (SnPP), the protective effect of NOB was attenuated. Overall, these results indicate that NOB exerts an outstanding neuroprotective effect on RGCs of glaucomatous neurodegeneration. Besides, interventions to enhance activation of Nrf2/HO-1 pathway can slow the loss of RGCs and are viable therapies for glaucoma.


Asunto(s)
Glaucoma , Fármacos Neuroprotectores , Hipertensión Ocular , Ratas , Animales , Células Ganglionares de la Retina , Factor 2 Relacionado con NF-E2/metabolismo , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Fármacos Neuroprotectores/metabolismo , Modelos Animales de Enfermedad , Hipertensión Ocular/tratamiento farmacológico , Hipertensión Ocular/metabolismo , Glaucoma/tratamiento farmacológico , Glaucoma/metabolismo , Hipoxia/metabolismo
16.
Exp Eye Res ; 217: 108979, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35143835

RESUMEN

Excitotoxicity-induced retinal neuronal death is characterized by the progressive retinal ganglion cell (RGC) apoptosis. Strategies are needed to reduce neurodegeneration. Recent investigations have indicated the potential effects of metformin on multiple systems, especially in the networks. However, it also remains unclear whether mitophagy contributes to the neuroprotective effect of metformin on the retina. In this study, excitotoxicity-induced retinal injury models were constructed. In vitro, R28 cells were treated with calcium ionophore and metformin/phosphate-buffer saline (PBS). Cell viability, lactate dehydrogenase release, and the cellular apoptosis rate were assessed. In vivo, rats received intravitreal injection of N-methyl-D-aspartate and metformin/PBS. Comprehensive examinations including retrograde fluorescent gold labelling, Nissl's staining, full-field electroretinography, photopic negative response, optic coherence tomography and retinal imaging, transmission electron microscopy, western blotting, and quantitative polymerase chain reaction were conducted during the observation period. The viability of R28 cells was significantly increased in the metformin-treated group compared with the negative control group, while, the release of lactate dehydrogenase and R28 cell apoptosis showed a significant decrease. In vivo, metformin treatment significantly increased the number of surviving RGCs, the b/NR wave amplitude and the thickness of the inner retina but had no obvious adverse effects on the fundus. In the metformin-treated group, the morphology and number of mitochondria were better preserved, as observed for RGCs; mitochondrial autophagosomes were located in RGCs, as indicated by transmission electron microscopy; and the expression of mitophagy-related genes and proteins presented was significant regulated. These data indicated that the regulation of mitophagy by metformin improved the structure and function of RGCs.


Asunto(s)
Lesiones Oculares , Metformina , Enfermedades de la Retina , Animales , Apoptosis , Lesiones Oculares/metabolismo , Lactato Deshidrogenasas/metabolismo , Metformina/metabolismo , Metformina/farmacología , Mitofagia , N-Metilaspartato/farmacología , Ratas , Enfermedades de la Retina/metabolismo , Células Ganglionares de la Retina/metabolismo
17.
Amino Acids ; 54(12): 1585-1599, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36056163

RESUMEN

Oxidative-induced damage and hypoxia/re-oxygenation (H/R) injury are common causes of irreversible visual impairment. The goals of this study were to explore the effects of taurine on R28 cells under the two damage models and the underlying mechanisms. Low doses of taurine supplementation promoted cell viability, mitochondrial membrane potential (MMP), SOD levels, ATP contents and attenuated cytotoxicity and intracellular ROS generation of the R28 cells under the two kinds of damage. The expression level of GTPBP3, a mitochondrial-tRNA (mt-tRNA) modification enzyme that catalyzes the taurine involved modification, was decreased under the two damage and taurine could reverse the reduction. After knocking down GTPBP3, the R28 cells become vulnerable to damage. The viability, cytotoxicity, MMP and intracellular ROS level of knockdown cells changed more obviously under the H/R injury than those of control cell. We also found that knockdown of GTPBP3 significantly decreased mitochondrial energy metabolism by measuring the oxidative respiration rate by the Seahorse XFe24 extracellular flux analyzer. The protection of low doses of taurine disappeared on knockdown R28 cells, indicating that GTPBP3 is crucial in the protection mechanisms of taurine. However, the impacts of the reduction of GTPBP3 level can be reversed by relatively high doses of taurine, implying the protection effects of taurine were dose-dependent, and there were more complicated mechanisms remain to be explored. This study explored a new mechanism of the neuroprotective effects of taurine, which depend on the GTPBP3-mediated taurine modification of mt-tRNAs and the promotion of mitochondrial energy metabolism.


Asunto(s)
Proteínas de Unión al GTP , Taurina , Metabolismo Energético , Proteínas de Unión al GTP/genética , Hipoxia , Potencial de la Membrana Mitocondrial , Especies Reactivas de Oxígeno/metabolismo , ARN de Transferencia/genética , Taurina/farmacología , Línea Celular , Animales , Ratas
18.
Molecules ; 27(6)2022 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-35335325

RESUMEN

Increasing evidence indicates that nobiletin (NOB) is a promising neuroprotective agent. Astrocyte activation plays a key role in neurodegenerative disorders. Thus, this study aims to investigate the effects of NOB on astrocyte activation and the potential mechanisms. In this study, astrocytes were exposed to hypoxia injury for 24 h to induce activation in vitro. Glial fibrillary acidic protein (GFAP) was chosen as a marker of astrocyte activation. To evaluate the effects of NOB on the migration of activated astrocytes, we used a scratch wound healing assay and Transwell migration assay. In addition, the levels of reactive oxygen species (ROS), malondialdehyde (MDA), mitochondrial membrane potential, Nrf2 and HO-1 were measured to investigate the mechanisms of NOB in the activation of astrocytes. We found that NOB alleviated astrocyte activation and decreased GFAP expression during hypoxia. Simultaneously, NOB alleviated the migration of astrocytes induced by hypoxia. With NOB treatment, hypoxia-induced oxidative stress was partially reversed, including reducing the production of ROS and MDA. Furthermore, NOB significantly improved the mitochondrial dysfunction in activated astrocytes. Finally, NOB promoted Nrf2 nuclear translocation and HO-1 expression in response to continuous oxidative damage. Our study indicates, for the first time, that NOB alleviates the activation of astrocytes induced by hypoxia in vitro, in part by ameliorating oxidative stress and mitochondrial dysfunction. This provides new insights into the neuroprotective effects of NOB.


Asunto(s)
Astrocitos , Estrés Oxidativo , Células Cultivadas , Flavonas , Humanos , Hipoxia/metabolismo
19.
Molecules ; 27(19)2022 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-36235043

RESUMEN

Marinated vegetables are traditional cold dishes with a long history and special flavor in the Chinese deli market. However, the traditional thermal-and-soaking (TS) procedure often results in unreproducible flavor quality properties of marinated vegetables and waste of brine and time in production. A novel green and sustainable technique, high-pressure processing (HPP), has caught the attention of the food industry. In this study, the effects of HPP and TS treatment on the visual, flavor, textural, and microbiological qualities of Chinese marinated lotus root slices were investigated. Compared to the TS products, lighter color, more varieties of volatile compounds, and crunchier texture were detected in the HPP products. Throughout the 4 °C, 25 °C, and 45 °C shelf life challenges, the HPP products retained their original color and crunchiness better than the TS ones, whereas no significant differences were found in total viable counts (TVCs) in the first half of the shelf lives. The Arrhenius model under the first-order reaction of TVC deterioration showed a good fit to the shelf life of the HPP marinated lotus root slices. This study demonstrates that HPP may assist in making the best use of brine in a more time-efficient manner to improve the visual, flavor, and textural quality of traditional Chinese marinated lotus root slices.


Asunto(s)
Sales (Química) , Verduras , China , Manipulación de Alimentos/métodos , Industria de Procesamiento de Alimentos
20.
J Neurochem ; 157(3): 550-560, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33305362

RESUMEN

Caveolin-1(Cav-1) is involved in lipid metabolism and energy homeostasis, which is important for the energetically demanding retina. Although retinal function deficits were noted in Cav-1 knockout (Cav-1-/- ) mice, the underlying causes remain largely unknown. Here, we investigate if the disruption in energy homeostasis presents a potential mechanism for retinal function deficits in Cav-1-/- retina and if it can be ameliorated by nicotinamide (NAM). In this study, NAM was administrated orally for 2 weeks in Cav-1-/- mice before experiments. Oxidative lipidomics was conducted to detect the oxylipin changes, the retinal energy flux was measured by seahorse assay, and the retinal function was assessed by electroretinogram (ERG). Cav-1 deficiency induced the dysregulation of oxidative lipidomics and reduction in energy consumption/production in the retina by decreasing Na+ /K+ -ATPase, oxidative phosphorylation CII, cytochrome c, and oxygen consumption rate (OCR). A decrease in Sirt1 was also detected. Therapeutic administration of NAM significantly increased Sirt1 expression and improved energy deficiency by increasing Na+ /K+ -ATPase, cytochrome c, and OCR. The dysregulation of oxidative lipidomics was partially recovered, and the retinal function was improved as assessed by ERG compared to Cav-1-/- mice. Our study demonstrated the dysregulation of oxidative lipidomics in Cav-1-/- retina and established a link between energy deficiency and retinal function deficits in Cav-1-/- mice. Administration of NAM ameliorated energy deficiency, increased the expression of Sirt1, and improved retinal function, which presents a potential therapeutic strategy for Cav-1 deficiency-induced retinal function deficits.


Asunto(s)
Caveolina 1/genética , Metabolismo Energético/efectos de los fármacos , Niacinamida/farmacología , Retina/efectos de los fármacos , Retina/metabolismo , Complejo Vitamínico B/farmacología , Animales , Electrorretinografía , Lipidómica , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fosforilación Oxidativa/efectos de los fármacos , Consumo de Oxígeno/efectos de los fármacos , Oxilipinas/metabolismo , Sirtuina 1/efectos de los fármacos , Sirtuina 1/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/metabolismo
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