Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 45
Filtrar
1.
Proc Natl Acad Sci U S A ; 119(19): e2117553119, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35522714

RESUMO

Regional phenotypic and functional differences in the retinal pigment epithelium (RPE) monolayer have been suggested to account for regional susceptibility in ocular diseases such as age-related macular degeneration (AMD), late-onset retinal degeneration (L-ORD), and choroideremia (CHM). However, a comprehensive description of human topographical RPE diversity is not yet available, thus limiting the understanding of regional RPE diversity and degenerative disease sensitivity in the eye. To develop a complete morphometric RPE map of the human eye, artificial intelligence­based software was trained to recognize, segment, and analyze RPE borders. Five statistically different, concentric RPE subpopulations (P1 to P5) were identified using cell area as a parameter, including a subpopulation (P4) with cell area comparable to that of macular cells in the far periphery of the eye. This work provides a complete reference map of human RPE subpopulations and their location in the eye. In addition, the analysis of cadaver non-AMD and AMD eyes and ultra-widefield fundus images of patients revealed differential vulnerability of the five RPE subpopulations to different retinal diseases.


Assuntos
Macula Lutea , Doenças Retinianas , Inteligência Artificial , Humanos , Doenças Retinianas/genética , Epitélio Pigmentado da Retina
2.
J Anat ; 243(2): 265-273, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-35778985

RESUMO

Saffron is an ancient spice largely used in traditional medicine. It has been found to be effective in treatment of retinal neurodegenerative diseases like age-related macular degeneration and Stargardt. In the present manuscript, it is shown that saffron's neuroprotective power is strongly related to the bioactivity of all its chemical components. Nuclear magnetic resonance spectroscopy and "in vitro" experiments confirm the relevance of crocins for saffron efficacy. These results underline the importance of strictly defining the chemical composition of the natural compounds in saffron to optimize their effectiveness in the treatment of diseases.


Assuntos
Crocus , Doenças Neurodegenerativas , Crocus/química , Doenças Neurodegenerativas/tratamento farmacológico
3.
Molecules ; 28(4)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36838685

RESUMO

Saffron treatment is a broad-spectrum therapy used for several retinal diseases, and its effectiveness depends on a particular molecular composition (REPRON® saffron). Its production requires specific crops and procedures that, together with low yields, make this spice expensive. To reduce costs, the use of hydroponic crops is gradually increasing. In this study, we tested the protective properties of a hydroponic saffron (sH) batch in models of retinal pigmented epithelium (RPE) degeneration. ARPE-19 cells were pretreated with 40 µg/mL saffron and exposed to different types of damage: excess light and retinol (LE + RET) or oxidative stress (H2O2). After analyzing the composition of all saffron types with spectroscopy, we performed cell viability and immunofluorescence analysis for both protocols. We compared the sH results with those of a validated batch of saffron REPRON® (sR) and those of a saffron non-REPRON® (sNR) batch. sH and sR, which we found had the same chemical composition, were more effective than sNR in increasing cell survival and attenuating the morphological changes related to apoptosis. In conclusion, hydroponic culturing is a suitable strategy to produce high-quality saffron to reduce costs and increase the accessibility of this promising treatment for retinal degeneration.


Assuntos
Crocus , Crocus/metabolismo , Peróxido de Hidrogênio/farmacologia , Epitélio Pigmentado da Retina/metabolismo , Linhagem Celular , Estresse Oxidativo , Corantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo
4.
Molecules ; 27(24)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36558107

RESUMO

Soilless cultivation of saffron (Crocus sativus) in a controlled environment represents an interesting alternative to field cultivation, in order to obtain a standardized high-quality product and to optimize yields. In particular, pharma-grade saffron is fundamental for therapeutic applications of this spice, whose efficacy has been demonstrated in the treatment of macular diseases, such as Age-related Macular Degeneration (AMD). In this work, a hydroponic cultivation system was developed, specifically designed to meet the needs of C. sativus plant. Various cultivation recipes, different in spectrum and intensity of lighting, temperature, photoperiod and irrigation, have been adopted to study their effect on saffron production. The experimentation involved the cultivation of corms from two subsequent farm years, to identify and validate the optimal conditions, both in terms of quantitative yield and as accumulation of bioactive metabolites, with particular reference to crocins and picrocrocin, which define the 'pharma-grade' quality of saffron. Through HPLC analysis and chromatography it was possible to identify the cultivation parameters suitable for the production of saffron with neuroprotective properties, evaluated by comparison with an ISO standard and the REPRON® procedure. Furthermore, the biochemical characterization was completed through NMR and high-resolution mass spectrometry analyses of saffron extracts. The whole experimental framework allowed to establish an optimized protocol to produce pharma-grade saffron, allowing up to 3.2 g/m2 harvest (i.e., more than three times higher than field production in optimal conditions), which meets the standards of composition for the therapy of AMD.


Assuntos
Crocus , Crocus/química , Fazendas , Hidroponia , Agricultura Molecular , Agricultura , Extratos Vegetais/química
5.
Molecules ; 25(23)2020 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-33260389

RESUMO

Crocus sativus L. belongs to the Iridaceae family and it is commonly known as saffron. The different cultures together with the geoclimatic characteristics of the territory determine a different chemical composition that characterizes the final product. This is why a complete knowledge of this product is fundamental, from which more than 150 chemical compounds have been extracted from, but only about one third of them have been identified. The chemical composition of saffron has been studied in relation to its efficacy in coping with neurodegenerative retinal diseases. Accordingly, experimental results provide evidence of a strict correlation between chemical composition and neuroprotective capacity. We found that saffron's ability to cope with retinal neurodegeneration is related to: (1) the presence of specific crocins and (2) the contribution of other saffron components. We summarize previous evidence and provide original data showing that results obtained both "in vivo" and "in vitro" lead to the same conclusion.


Assuntos
Crocus/química , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/farmacologia , Animais , Cálcio/metabolismo , Carotenoides/química , Carotenoides/metabolismo , Carotenoides/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular , Cromatografia Líquida de Alta Pressão , Crocus/metabolismo , Modelos Animais de Doenças , Flores/química , Células HEK293 , Humanos , Luz/efeitos adversos , Camundongos , Doenças Neurodegenerativas/tratamento farmacológico , Fármacos Neuroprotetores/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Ratos Sprague-Dawley , Receptores Purinérgicos P2X7/efeitos dos fármacos , Retina/diagnóstico por imagem , Retina/efeitos dos fármacos , Degeneração Retiniana/tratamento farmacológico , Degeneração Retiniana/etiologia , Vitamina A/análogos & derivados , Vitamina A/metabolismo
6.
Nat Mater ; 16(6): 681-689, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28250420

RESUMO

The degeneration of photoreceptors in the retina is one of the major causes of adult blindness in humans. Unfortunately, no effective clinical treatments exist for the majority of retinal degenerative disorders. Here we report on the fabrication and functional validation of a fully organic prosthesis for long-term in vivo subretinal implantation in the eye of Royal College of Surgeons rats, a widely recognized model of retinitis pigmentosa. Electrophysiological and behavioural analyses reveal a prosthesis-dependent recovery of light sensitivity and visual acuity that persists up to 6-10 months after surgery. The rescue of the visual function is accompanied by an increase in the basal metabolic activity of the primary visual cortex, as demonstrated by positron emission tomography imaging. Our results highlight the possibility of developing a new generation of fully organic, highly biocompatible and functionally autonomous photovoltaic prostheses for subretinal implants to treat degenerative blindness.


Assuntos
Cegueira/fisiopatologia , Cegueira/terapia , Compostos Orgânicos , Recuperação de Função Fisiológica , Visão Ocular , Próteses Visuais , Animais , Modelos Animais de Doenças , Ratos
7.
Purinergic Signal ; 12(1): 161-74, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26739703

RESUMO

P2X7-type purinergic receptors are distributed throughout the nervous system where they contribute to physiological and pathological functions. In the retina, this receptor is found in both inner and outer cells including microglia modulating signaling and health of retinal cells. It is involved in retinal neurodegenerative disorders such as retinitis pigmentosa and age-related macular degeneration (AMD). Experimental studies demonstrated that saffron protects photoreceptors from light-induced damage preserving both retinal morphology and visual function and improves retinal flicker sensitivity in AMD patients. To evaluate a possible interaction between saffron and P2X7 receptors (P2X7Rs), different cellular models and experimental approaches were used. We found that saffron positively influences the viability of mouse primary retinal cells and photoreceptor-derived 661W cells exposed to ATP, and reduced the ATP-induced intracellular calcium increase in 661W cells. Similar results were obtained on HEK cells transfected with recombinant rat P2X7R but not on cells transfected with rat P2X2R. Finally, patch-clamp experiments showed that saffron inhibited cationic currents in HEK-P2X7R cells. These results point out a novel mechanism through which saffron may exert its protective role in neurodegeneration and support the idea that P2X7-mediated calcium signaling may be a crucial therapeutic target in the treatment of neurodegenerative diseases.


Assuntos
Trifosfato de Adenosina/antagonistas & inibidores , Trifosfato de Adenosina/toxicidade , Crocus , Extratos Vegetais/uso terapêutico , Receptores Purinérgicos P2X7/efeitos dos fármacos , Doenças Retinianas/induzido quimicamente , Doenças Retinianas/prevenção & controle , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Técnicas de Patch-Clamp , Células Fotorreceptoras de Vertebrados/efeitos dos fármacos , Cultura Primária de Células , Ratos , Receptores Purinérgicos P2X7/genética , Retina/citologia , Retina/patologia , Doenças Retinianas/patologia
8.
Vis Neurosci ; 31(4-5): 355-61, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24819927

RESUMO

Age-related macular degeneration (AMD) is a retinal neurodegenerative disease whose development and progression are the results of a complex interaction between genetic and environmental risk factors. Both oxidative stress and chronic inflammation play a significant role in the pathogenesis of AMD. Experimental studies in rats with light-induced photoreceptors degeneration demonstrated that saffron may protect photoreceptor from retinal stress, preserving both morphology and function and probably acting as a regulator of programmed cell death, in addition to its antioxidant and anti-inflammatory properties. Recently, a randomized clinical trial showed that in patients with early AMD, dietary supplementation with saffron was able to improve significantly the retinal flicker sensitivity suggesting neuroprotective effect of the compound. Here, we examine the progress of saffron dietary supplementation both in animal model and AMD patients, and discuss the potential and safety for using dietary saffron to treat retinal degeneration.


Assuntos
Crocus , Degeneração Macular/patologia , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/farmacocinética , Retina/efeitos dos fármacos , Animais , Humanos , Degeneração Macular/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Fitoterapia , Retina/metabolismo
9.
J Transl Med ; 11: 228, 2013 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-24067115

RESUMO

BACKGROUND: To determine whether the functional effects of oral supplementation with Saffron, a natural compound that proved to be neuroprotective in early age-related macular degeneration, are influenced by complement factor H (CFH) and age-related maculopathy susceptibility 2 (ARMS2) risk genotypes. METHODS: Thirty-three early AMD patients, screened for CFH (rs1061170) and ARMS2 (rs10490924) polymorphisms and receiving Saffron oral supplementation (20 mg/day) over an average period of treatment of 11 months (range, 6-12), were longitudinally evaluated by clinical examination and focal electroretinogram (fERG)-derived macular (18°) flicker sensitivity estimate. fERG amplitude and macular sensitivity, the reciprocal value of the estimated fERG amplitude threshold, were the main outcome measures. RESULTS: After three months of supplementation, mean fERG amplitude and fERG sensitivity improved significantly when compared to baseline values (p < 0.01). These changes were stable throughout the follow-up period. No significant differences in clinical and fERG improvements were observed across different CFH or ARMS2 genotypes. CONCLUSIONS: The present results indicate that the functional effect of Saffron supplementation in individual AMD patients is not related to the major risk genotypes of disease.


Assuntos
Crocus/química , Suplementos Nutricionais , Predisposição Genética para Doença , Degeneração Macular/tratamento farmacológico , Degeneração Macular/genética , Extratos Vegetais/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Fator H do Complemento/genética , Demografia , Eletrorretinografia , Feminino , Heterozigoto , Humanos , Degeneração Macular/fisiopatologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Proteínas/genética , Fatores de Risco
10.
Pharmaceuticals (Basel) ; 16(9)2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37765115

RESUMO

A mechanism shared by most neurodegenerative diseases, like Alzheimer's disease (AD) and Parkinson's disease (PD), is neuroinflammation. It has been shown to have a link between cognitive impairment and retinal function under neuroinflammatory conditions, confirming the essential role of the retina as a window to the brain. Here, we characterize a mouse model of LPS-induced neuroinflammation describing the parallel deterioration of both memory and visual function. Then, we demonstrate, using the Novel Object Recognition test (NOR) and electroretinogram (ERG) recordings, that preventive, chronic treatment with saffron Repron® is able to reduce the neuroinflammation process and prevent the impairment of both cognitive and visual function. The improvement in behavioral and visual function is confirmed by the pattern of expression of neuroinflammation-related genes and related proteins where pre-treatment with Repron® saffron presents a positive modulation compared with that obtained in animals treated with LPS alone. These results hold for retinal tissue and partially in the brain, where it appears that the onset of damage was delayed. This trend underlines the critical role of the retina as a most sensitive portion of the central nervous system to LPS-induced damage and could be used as a "sensor" for the early detection of neurodegenerative diseases such as Alzheimer's.

11.
Sci Rep ; 12(1): 21561, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36513717

RESUMO

Visual information processing in the retina requires the rhythmic expression of clock genes. The intrinsic retinal circadian clock is independent of the master clock located in the hypothalamic suprachiasmatic nucleus and emerges from retinal cells, including glia. Less clear is how glial oscillators influence the daily regulation of visual information processing in the mouse retina. Here, we demonstrate that the adult conditional deletion of the gene Bmal1 in GLAST-positive glial cells alters retinal physiology. Specifically, such deletion was sufficient to lower the amplitude of the electroretinogram b-wave recorded under light-adapted conditions. Furthermore, recordings from > 20,000 retinal ganglion cells (RGCs), the retina output, showed a non-uniform effect on RGCs activity in response to light across different cell types and over a 24-h period. Overall, our results suggest a new role of a glial circadian gene in adjusting mammalian retinal output throughout the night-day cycle.


Assuntos
Relógios Circadianos , Ritmo Circadiano , Animais , Camundongos , Relógios Circadianos/genética , Ritmo Circadiano/fisiologia , Mamíferos , Neuroglia , Retina/metabolismo , Núcleo Supraquiasmático/fisiologia
12.
Cells ; 10(6)2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-34205615

RESUMO

Retinal neurodegeneration can impair visual perception at different levels, involving not only photoreceptors, which are the most metabolically active cells, but also the inner retina. Compensatory mechanisms may hide the first signs of these impairments and reduce the likelihood of receiving timely treatments. Therefore, it is essential to characterize the early critical steps in the neurodegenerative progression to design adequate therapies. This paper describes and correlates early morphological and biochemical changes in the degenerating retina with in vivo functional analysis of retinal activity and investigates the progression of neurodegenerative stages for up to 7 months. For these purposes, Sprague-Dawley rats were exposed to 1000 lux light either for different durations (12 h to 24 h) and examined seven days afterward (7d) or for a fixed duration (24 h) and monitored at various time points following the exposure (up to 210d). Flash electroretinogram (fERG) recordings were correlated with morphological and histological analyses to evaluate outer and inner retinal disruptions, gliosis, trophic factor release, and microglial activation. Twelve hours or fifteen hours of exposure to constant light led to a severe retinal dysfunction with only minor morphological changes. Therefore, early pathological signs might be hidden by compensatory mechanisms that silence retinal dysfunction, accounting for the discrepancy between photoreceptor loss and retinal functional output. The long-term analysis showed a transient functional recovery, maximum at 45 days, despite a progressive loss of photoreceptors and coincident increases in glial fibrillary acidic protein (GFAP) and basic fibroblast growth factor-2 (bFGF-2) expression. Interestingly, the progression of the disease presented different patterns in the dorsal and ventral retina. The information acquired gives us the potential to develop a specific diagnostic tool to monitor the disease's progression and treatment efficacy.


Assuntos
Fator 2 de Crescimento de Fibroblastos/biossíntese , Regulação da Expressão Gênica/efeitos da radiação , Proteína Glial Fibrilar Ácida/biossíntese , Luz , Retina , Degeneração Retiniana , Animais , Eletrorretinografia , Ratos , Ratos Sprague-Dawley , Retina/metabolismo , Retina/patologia , Retina/fisiopatologia , Degeneração Retiniana/metabolismo , Degeneração Retiniana/patologia , Degeneração Retiniana/fisiopatologia , Fatores de Tempo
13.
Nutrients ; 13(3)2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33673449

RESUMO

Retinal diseases can be induced by a variety of factors, including gene mutations, environmental stresses and dysmetabolic processes. The result is a progressive deterioration of visual function, which sometimes leads to blindness. Many treatments are under investigation, though results are still mostly unsatisfactory and restricted to specific pathologies, particularly in the case of gene therapy. The majority of treatments have been tested in animal models, but very few have progressed to human clinical trials. A relevant approach is to study the relation between the type of treatments and the degenerative characteristics of the animal model to better understand the effectiveness of each therapy. Here we compare the results obtained from different animal models treated with natural compounds (saffron and naringenin) to anticipate the potentiality of a single treatment in different pathologies.


Assuntos
Crocus , Flavanonas/uso terapêutico , Doenças Neurodegenerativas/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Doenças Retinianas/tratamento farmacológico , Neurônios Retinianos/patologia , Envelhecimento , Animais , Suplementos Nutricionais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Extratos Vegetais/química , Ratos , Ratos Endogâmicos F344 , Doenças Retinianas/patologia , Neurônios Retinianos/efeitos dos fármacos
14.
J Neurosci ; 29(43): 13691-701, 2009 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-19864581

RESUMO

Early sensory experience shapes the functional and anatomical connectivity of neuronal networks. Light deprivation alters synaptic transmission and modifies light response properties in the visual system, from retinal circuits to higher visual centers. These effects are more pronounced during a critical period in juvenile life and are mostly reversed by restoring normal light conditions. Here we show that complete light deprivation, from birth to periods beyond the critical period, permanently modifies the receptive field properties of retinal ganglion cells. Visual deprivation reduced both the strength of light responses in ganglion cells and their receptive field size. Light deprivation produced an imbalance in the ratio of inhibitory to excitatory inputs, with a shift toward larger inhibitory conductances. Ganglion cell receptive fields in visually deprived animals showed a spatial mismatch of inhibitory and excitatory inputs and inhibitory inputs were highly scattered over the receptive field. These results indicate that visual experience early in life is critical for the refinement of retinal circuits and for appropriate signaling of the spatiotemporal properties of visual stimuli, thus influencing the response properties of neurons in higher visual centers and their processing of visual information.


Assuntos
Plasticidade Neuronal/fisiologia , Retina/anatomia & histologia , Retina/fisiologia , Privação Sensorial/fisiologia , Vias Visuais/anatomia & histologia , Vias Visuais/fisiologia , Potenciais de Ação , Animais , Animais Recém-Nascidos , Escuridão , Condutividade Elétrica , Luz , Inibição Neural/fisiologia , Técnicas de Patch-Clamp , Estimulação Luminosa , Ratos , Ratos Long-Evans , Retina/crescimento & desenvolvimento , Células Ganglionares da Retina/fisiologia , Potenciais Sinápticos , Fatores de Tempo , Visão Ocular/fisiologia , Vias Visuais/crescimento & desenvolvimento
15.
Mol Vis ; 16: 1801-22, 2010 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-20844572

RESUMO

PURPOSE: To identify the genes and noncoding RNAs (ncRNAs) involved in the neuroprotective actions of a dietary antioxidant (saffron) and of photobiomodulation (PBM). METHODS: We used a previously published assay of photoreceptor damage, in which albino Sprague Dawley rats raised in dim cyclic illumination (12 h 5 lux, 12 h darkness) were challenged by 24 h exposure to bright (1,000 lux) light. Experimental groups were protected against light damage by pretreatment with dietary saffron (1 mg/kg/day for 21 days) or PBM (9 J/cm(2) at the eye, daily for 5 days). RNA from one eye of four animals in each of the six experimental groups (control, light damage [LD], saffron, PBM, saffronLD, and PBMLD) was hybridized to Affymetrix rat genome ST arrays. Quantitative real-time PCR analysis of 14 selected genes was used to validate the microarray results. RESULTS: LD caused the regulation of 175 entities (genes and ncRNAs) beyond criterion levels (p<0.05 in comparison with controls, fold-change >2). PBM pretreatment reduced the expression of 126 of these 175 LD-regulated entities below criterion; saffron pretreatment reduced the expression of 53 entities (50 in common with PBM). In addition, PBM pretreatment regulated the expression of 67 entities not regulated by LD, while saffron pretreatment regulated 122 entities not regulated by LD (48 in common with PBM). PBM and saffron, given without LD, regulated genes and ncRNAs beyond criterion levels, but in lesser numbers than during their protective action. A high proportion of the entities regulated by LD (>90%) were known genes. By contrast, ncRNAs were prominent among the entities regulated by PBM and saffron in their neuroprotective roles (73% and 62%, respectively). CONCLUSIONS: Given alone, saffron and (more prominently) PBM both regulated significant numbers of genes and ncRNAs. Given before retinal exposure to damaging light, thus while exerting their neuroprotective action, they regulated much larger numbers of entities, among which ncRNAs were prominent. Further, the downregulation of known genes and of ncRNAs was prominent in the protective actions of both neuroprotectants. These comparisons provide an overview of gene expression induced by two neuroprotectants and provide a basis for the more focused study of their mechanisms.


Assuntos
Antioxidantes/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Luz , Análise de Sequência com Séries de Oligonucleotídeos , Células Fotorreceptoras de Vertebrados/citologia , RNA não Traduzido/genética , Retina/metabolismo , Animais , Morte Celular/efeitos dos fármacos , Análise por Conglomerados , Crocus/química , Citoproteção/efeitos dos fármacos , Citoproteção/efeitos da radiação , Dieta , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos da radiação , Fatores Imunológicos/farmacologia , Células Fotorreceptoras de Vertebrados/efeitos dos fármacos , Células Fotorreceptoras de Vertebrados/metabolismo , Células Fotorreceptoras de Vertebrados/efeitos da radiação , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Retina/efeitos dos fármacos , Retina/efeitos da radiação , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Biomolecules ; 10(5)2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32354031

RESUMO

Age-related macular degeneration (AMD) is one of the leading causes of visual loss in western countries, it has no cure, and its incidence will grow in the future, for the overall population aging. Albino rats with retinal degeneration induced by exposure to high-intensity light (light-damage, LD) have been extensively used as a model of AMD to test neuroprotective agents. Among them, trophic factors (NGF and BDNF) have been shown to play a significant role in photoreceptors' survival. Interestingly, cord blood serum (CBS) is an extract full of chemokines and trophic factors; we, therefore, hypothesized that CBS could be an excellent candidate for neuroprotection. Here, we investigate whether CBS-based eye drops might mitigate the effects of light-induced retinal degeneration in albino rats. CBS treatment significantly preserved flash-electroretinogram (f-ERG) response after LD and reduced the "hot-spot" extension. Besides, CBS-treated animals better preserved the morphology of the outer nuclear layer, together with a reduction in microglia migration and activation. Interestingly, the treatment did not modulate reactive gliosis and activation of the self-protective mechanism (FGF2). In conclusion, our results suggest that CBS-based eye drops might be successfully used to mitigate retinal neurodegenerative processes such as AMD.


Assuntos
Sangue Fetal/química , Degeneração Macular/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Soluções Oftálmicas/farmacologia , Células Fotorreceptoras/efeitos dos fármacos , Animais , Fator de Crescimento Epidérmico/análise , Fator de Crescimento Epidérmico/farmacologia , Feminino , Humanos , Interleucinas/análise , Interleucinas/farmacologia , Luz/efeitos adversos , Degeneração Macular/etiologia , Microglia/efeitos dos fármacos , Fatores de Crescimento Neural/análise , Fatores de Crescimento Neural/farmacologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/uso terapêutico , Soluções Oftálmicas/química , Soluções Oftálmicas/uso terapêutico , Ratos , Ratos Sprague-Dawley , Soro/química
17.
PLoS One ; 15(6): e0234145, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32497126

RESUMO

Oxidative stress and inflammation determine retinal ganglion cell degeneration, leading to retinal impairment and vision loss. Müller glial cells regulate retinal repair under injury, through gliosis. Meanwhile, reactive gliosis can turn in pathological effects, contributing to neurodegeneration. In the present study, we tested whether Cord Blood Serum (CBS), rich of growth factors, might improve the viability of Müller cells under in vitro damage. BDNF, NGF, TGF-α, GDNF and EGF levels were measured in CBS samples by Human Magnetic Luminex Assay. CBS effects were evaluated on rat (rMC-1) and human (MIO-M1) Müller cells, under H2O2 and IL-1ß damage. Cells grown with FBS or CBS both at 5% were exposed to stress and analyzed in terms of cell viability, GFAP, IL-6 and TNF-α expression. CBS was also administrated after treatment with K252a, inhibitor of the neurotrophin receptor Trk. Cell viability of rMC-1 and MIO-M1 resulted significantly improved when pretreated with CBS and exposed to H2O2 and IL-1ß, in comparison to the standard culture with FBS. Accordingly, the gliosis marker GFAP resulted down-regulated following CBS priming. In parallel, we observed a lower expression of the inflammatory mediators in rMC-1 (TNF-α) and MIO-M1 (IL-6, TNF- α), especially in presence of inflammatory damage. Trk inhibition through K252a administration impaired the effects of CBS under stress conditions on MIO-M1 and rMC-1 viability, not significantly different from FBS condition. CBS is enriched with neurotrophins and its administration to rMC-1 and MIO-M1 attenuates the cytotoxic effects of H2O2 and IL-1ß. Moreover, the decrease of the main markers of gliosis and inflammation suggests a promising use of CBS for neuroprotection aims. This study is a preliminary basis that prompts future investigations to deeply explore and confirm the CBS potential.


Assuntos
Células Ependimogliais/citologia , Células Ependimogliais/efeitos dos fármacos , Sangue Fetal/metabolismo , Soro/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Ependimogliais/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/genética , Humanos , Estresse Oxidativo/efeitos dos fármacos , Polissacarídeos/metabolismo , Ratos , Fator de Necrose Tumoral alfa/metabolismo
18.
Cells ; 9(8)2020 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-32756469

RESUMO

The high mortality rate of colorectal cancer (CRC) patients is directly associated with metastatic dissemination. However, therapeutic options specifically for metastasis are still limited. We previously identified Metastasis-Associated in Colon Cancer 1 (MACC1) as a major causal metastasis-inducing gene. Numerous studies confirmed its value as a biomarker for metastasis risk. We investigated the inhibitory impact of saffron on MACC1-induced cancer cell growth and motility. Saffron crudes restricted the proliferation and migration of MACC1-expressing CRC cells in a concentration- and MACC1-dependent manner. Saffron delays cell cycle progression at G2/M-phase and does not induce apoptosis. Rescue experiments showed that these effects are reversible. Analysis of active saffron compounds elucidated that crocin was the main compound that reproduced total saffron crudes effects. We showed the interaction of MACC1 with the cancer stem cell (CSC) marker DCLK1, which contributes to metastasis formation in different tumor entities. Saffron extracts reduced DCLK1 with crocin being responsible for this reduction. Saffron's anti-proliferative and anti-migratory effects in MACC1-expressing cells are mediated by crocin through DCLK1 down-regulation. This research is the first identification of saffron-based compounds restricting cancer cell proliferation and motility progression via the novel target MACC1.


Assuntos
Antineoplásicos/farmacologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/patologia , Crocus/química , Transativadores/metabolismo , Antineoplásicos/química , Carotenoides/análise , Carotenoides/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Quinases Semelhantes a Duplacortina , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Transativadores/genética
19.
Front Bioeng Biotechnol ; 8: 579141, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33195139

RESUMO

The progressive degeneration of retinal photoreceptors is one of the most significant causes of blindness in humans. Conjugated polymers represent an attractive solution to the field of retinal prostheses, and a multi-layer fully organic prosthesis implanted subretinally in dystrophic Royal College of Surgeons (RCS) rats was able to rescue visual functions. As a step toward human translation, we report here the fabrication and in vivo testing of a similar device engineered to adapt to the human-like size of the eye of the domestic pig, an excellent animal paradigm to test therapeutic strategies for photoreceptors degeneration. The active conjugated polymers were layered onto two distinct passive substrates, namely electro-spun silk fibroin (ESF) and polyethylene terephthalate (PET). Naive pigs were implanted subretinally with the active device in one eye, while the contralateral eye was sham implanted with substrate only. Retinal morphology and functionality were assessed before and after surgery by means of in vivo optical coherence tomography and full-field electroretinogram (ff-ERG) analysis. After the sacrifice, the retina morphology and inflammatory markers were analyzed by immunohistochemistry of the excised retinas. Surprisingly, ESF-based prostheses caused a proliferative vitreoretinopathy with disappearance of the ff-ERG b-wave in the implanted eyes. In contrast, PET-based active devices did not evoke significant inflammatory responses. As expected, the subretinal implantation of both PET only and the PET-based prosthesis locally decreased the thickness of the outer nuclear layer due to local photoreceptor loss. However, while the implantation of the PET only substrate decreased the ff-ERG b-wave amplitude with respect to the pre-implant ERG, the eyes implanted with the active device fully preserved the ERG responses, indicating an active compensation of the surgery-induced photoreceptor loss. Our findings highlight the possibility of developing a new generation of conjugated polymer/PET-based prosthetic devices that are highly biocompatible and potentially suitable for subretinal implantation in patients suffering from degenerative blindness.

20.
Antioxidants (Basel) ; 8(7)2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31319529

RESUMO

Both age related macular degeneration (AMD) and light induced retinal damage share the common major role played by oxidative stress in the induction/progression of degenerative events. Light damaged (LD) rats have been widely used as a convenient model to gain insight into the mechanisms of degenerative disease, to enucleate relevant steps and to test neuroprotectants. Among them, saffron has been shown to ameliorate degenerative processes and to regulate many genes and protective pathways. Saffron has been also tested in AMD patients. We extended our analysis to a possible additional effect regulated by saffron and compared in AMD patients a pure antioxidant treatment (Lutein/zeaxanthin) with saffron treatment. Methods: Animal model. Sprague-Dawley (SD) adult rats, raised at 5 lux, were exposed to 1000 lux for 24 h and then either immediately sacrificed or placed back at 5 lux for 7 days recovery period. A group of animals was treated with saffron. We performed in the animal model: (1) SDS-PAGE analysis; (2) Western Blotting (3) Enzyme activity assay (4) Immunolabelling; in AMD patients: a longitudinal open-label study 29 (±5) months in two groups of patients: lutein/zeaxanthin (19) and saffron (23) treated. Visual function was tested every 8 months by ERG recordings in addition to clinical examination. Results: Enzymatic activity of MMP-3 is reduced in LD saffron treated retinas and is comparable to control as it is MMP-3 expression. LD treated retinas do not present "rosettes" and microglia activation and migration is highly reduced. Visual function remains stable in saffron treated AMD patients while deteriorates in the lutein/zeaxanthin group. Conclusion: Our results provide evidence of an additional way of action of saffron treatment confirming the complex nature of neuroprotective activities of its chemical components. Accordingly, long term follow-up in AMD patients reveals an added value of saffron supplementation treatment compared to classical antioxidant protocol.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA