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1.
Adv Exp Med Biol ; 1141: 467-504, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31571172

RESUMO

Blood-retinal barrier (BRB) includes inner BRB (iBRB) and outer BRB (oBRB), which are formed by retinal capillary endothelial (RCEC) cells and by retinal pigment epithelial (RPE) cells in collaboration with Bruch's membrane and the choriocapillaris, respectively. Functions of the BRB are to regulate fluids and molecular movement between the ocular vascular beds and retinal tissues and to prevent leakage of macromolecules and other potentially harmful agents into the retina, keeping the microenvironment of the retina and retinal neurons. These functions are mainly attributed to absent fenestrations of RCECs, tight junctions, expression of a great diversity of transporters, and coverage of pericytes and glial cells. BRB existence also becomes a reason that systemic administration for some drugs is not suitable for the treatment of retinal diseases. Some diseases (such as diabetes and ischemia-reperfusion) impair BRB function via altering tight junctions, RCEC death, and transporter expression. This chapter will illustrate function of BRB, expressions and functions of these transporters, and their clinical significances.


Assuntos
Barreira Hematorretiniana , Proteínas de Membrana Transportadoras , Expressão Gênica , Humanos , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Retina/metabolismo , Doenças Retinianas/fisiopatologia , Junções Íntimas
2.
BMC Evol Biol ; 19(1): 174, 2019 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-31462236

RESUMO

BACKGROUND: A number of non-visual responses to light in vertebrates, such as circadian rhythm control and pupillary light reflex, are mediated by melanopsins, G-protein coupled membrane receptors, conjugated to a retinal chromophore. In non-mammalian vertebrates, melanopsin expression is variable within the retina and extra-ocular tissues. Two paralog melanopsin genes were classified in vertebrates, Opn4x and Opn4m. Snakes are highly diversified vertebrates with a wide range of daily activity patterns, which raises questions about differences in structure, function and expression pattern of their melanopsin genes. In this study, we analyzed the melanopsin genes expressed in the retinas of 18 snake species from three families (Viperidae, Elapidae, and Colubridae), and also investigated extra-retinal tissue expression. RESULTS: Phylogenetic analysis revealed that the amplified gene belongs to the Opn4x group, and no expression of the Opn4m was found. The same paralog is expressed in the iris, but no extra-ocular expression was detected. Molecular evolutionary analysis indicated that melanopsins are evolving primarily under strong purifying selection, although lower evolutionary constraint was detected in snake lineages (ω = 0.2), compared to non-snake Opn4x and Opn4m (ω = 0.1). Statistical analysis of selective constraint suggests that snake phylogenetic relationships have driven stronger effects on melanopsin evolution, than the species activity pattern. In situ hybridization revealed the presence of melanopsin within cells in the outer and inner nuclear layers, in the ganglion cell layer, and intense labeling in the optic nerve. CONCLUSIONS: The loss of the Opn4m gene and extra-ocular photosensitive tissues in snakes may be associated with a prolonged nocturnal/mesopic bottleneck in the early history of snake evolution. The presence of melanopsin-containing cells in all retinal nuclear layers indicates a globally photosensitive retina, and the expression in classic photoreceptor cells suggest a regionalized co-expression of melanopsin and visual opsins.


Assuntos
Proteínas de Répteis/genética , Retina/metabolismo , Opsinas de Bastonetes/genética , Serpentes/genética , Animais , Relógios Circadianos , Evolução Molecular , Regulação da Expressão Gênica , Filogenia , Opsinas de Bastonetes/fisiologia , Serpentes/classificação , Serpentes/fisiologia , Visão Ocular
3.
J Photochem Photobiol B ; 197: 111543, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31279896

RESUMO

Taking into account the ultrastructure of the Pied Flycatcher foveal retina reported earlier and the earlier reported properties of Müller cell (MC) intermediate filaments (IFs) isolated from vertebrate retina, we proposed a quantum mechanism (QM) of light energy transfer from the inner limiting membrane level to visual pigments in the photoreceptor cells. This mechanism involves electronic excitation energy transfer in a donor-acceptor system, with the IFs excited by photons acting as energy donors, and visual pigments in the photoreceptor cells acting as energy acceptors. It was shown earlier that IFs with diameter 10 nm and length 117 µm isolated from vertebrate eye retina demonstrate properties of light energy guide, where exciton propagates along such IFs from MC endfeet area to photoreceptor cell area. The energy is mostly transferred via the contact exchange quantum mechanism. Our estimates demonstrate that energy transfer efficiencies in such systems may exceed 80-90%. Thus, the presently developed quantum mechanism of light energy transfer in the inverted retina complements the generally accepted classic optical mechanism and the mechanism whereby Müller cells transmit light like optical fibers. The proposed QM of light energy transfer in the inverted retina explains the high image contrast achieved in photopic conditions by an avian eye, being probably also active in other vertebrates.


Assuntos
Luz , Teoria Quântica , Retina/metabolismo , Animais , Aves , Transferência de Energia , Células Ependimogliais/metabolismo , Filamentos Intermediários/química , Células Fotorreceptoras/metabolismo , Retina/efeitos da radiação , Retinaldeído/química
4.
Life Sci ; 232: 116588, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31226418

RESUMO

AIMS: Retinopathy is a neurodegenerative complication associating diabetes mellitus. Diabetic retinopathy (DR) is the primary reason of visual loss during early adulthood. DR has a complicated multifactorial pathophysiology initiated by hyperglycaemia-induced ischaemic neurodegenerative retinal changes, followed by vision-threatening consequences. The main therapeutic modalities for DR involve invasive delivery of intravitreal antiangiogenic agents as well as surgical interventions. The current work aimed to explore the potential anti-inflammatory and retinal neuroprotective effects of levetiracetam. MAIN METHODS: This study was performed on alloxan-induced diabetes in mice (n: 21). After 10 weeks, a group of diabetic animals (n: 7) was treated with levetiracetam (25 mg/kg) for six weeks. Retinal tissues were dissected and paraffin-fixed for examination using (1) morphometric analysis with haematoxylin and eosin (HE), (2) immunohistochemistry (GLUT1, GFAP and GAP43), and (3) RT-PCR-detected expression of retinal inflammatory and apoptotic mediators (TNF-α, IL6, iNOS, NF-κB and Tp53). KEY FINDINGS: Diabetic mice developed disorganized and debilitated retinal layers with upregulation of the gliosis marker GFAP and downregulation of the neuronal plasticity marker GAP43. Additionally, diabetic retinae showed increased transcription of NF-κB, TNF-α, IL6, iNOS and Tp53. Levetiracetam-treated mice showed downregulation of retinal GLUT1 with relief and regression of retinal inflammation and improved retinal structural organization. SIGNIFICANCE: Levetiracetam may represent a potential neuroprotective agent in DR. The data presented herein supported an anti-inflammatory role of levetiracetam. However, further clinical studies may be warranted to confirm the effectiveness and safety of levetiracetam in DR patients.


Assuntos
Retinopatia Diabética/tratamento farmacológico , Retinopatia Diabética/metabolismo , Proteína GAP-43/biossíntese , Transportador de Glucose Tipo 1/biossíntese , Levetiracetam/farmacologia , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Retinopatia Diabética/sangue , Retinopatia Diabética/genética , Modelos Animais de Doenças , Proteína GAP-43/genética , Transportador de Glucose Tipo 1/genética , Imuno-Histoquímica , Inflamação/metabolismo , Interleucina-6/metabolismo , Masculino , Camundongos , NF-kappa B/metabolismo , Fármacos Neuroprotetores/farmacologia , Óxido Nítrico Sintase Tipo II/metabolismo , Retina/metabolismo , Doenças Retinianas/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
5.
Biochemistry (Mosc) ; 84(5): 479-490, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31234763

RESUMO

The review discusses the prospects of using rhodopsin as an optogenetic tool for prosthetics of degenerative (blind) eye retina and the principles of optogenetic techniques. Retinal-containing proteins that depolarize/hyperpolarize the plasma membrane of nerve cells and, accordingly, excite/inhibit physiological activity of neurons, are described. The problem of what cells of the degenerative retina can be treated with what particular rhodopsins is discussed in detail. Viruses and promoters required for the rhodopsin gene delivery into the degenerative retina cells are described. In conclusion, main concepts and tasks associated with the optogenetic prosthetic treatment of degenerative retina employing rhodopsins are presented.


Assuntos
Optogenética/métodos , Degeneração Retiniana/patologia , Animais , Terapia Genética , Humanos , Células Fotorreceptoras/metabolismo , Retina/metabolismo , Degeneração Retiniana/terapia , Células Ganglionares da Retina/metabolismo , Rodopsina/genética , Rodopsina/metabolismo
6.
Neuron ; 103(1): 39-51.e5, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31122676

RESUMO

Despite robust effects on immature neurons, growth factors minimally promote axon regeneration in the adult central nervous system (CNS). Attempting to improve growth-factor responsiveness in mature neurons by dedifferentiation, we overexpressed Lin28 in the retina. Lin28-treated retinas responded to insulin-like growth factor-1 (IGF1) by initiating retinal ganglion cell (RGC) axon regeneration after axotomy. Surprisingly, this effect was cell non-autonomous. Lin28 expression was required only in amacrine cells, inhibitory neurons that innervate RGCs. Ultimately, we found that optic-nerve crush pathologically upregulated activity in amacrine cells, which reduced RGC electrical activity and suppressed growth-factor signaling. Silencing amacrine cells or pharmacologically blocking inhibitory neurotransmission also induced IGF1 competence. Remarkably, RGCs regenerating across these manipulations localized IGF1 receptor to their primary cilia, which maintained their signaling competence and regenerative ability. Thus, our results reveal a circuit-based mechanism that regulates CNS axon regeneration and implicate primary cilia as a regenerative signaling hub.


Assuntos
Axônios/fisiologia , Fator de Crescimento Neural/fisiologia , Regeneração Nervosa/fisiologia , Receptores Pré-Sinápticos/fisiologia , Células Amácrinas/fisiologia , Animais , Cílios/metabolismo , Cílios/ultraestrutura , Fator de Crescimento Insulin-Like I/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Compressão Nervosa , Traumatismos do Nervo Óptico/patologia , Proteínas de Ligação a RNA/genética , Receptor IGF Tipo 1/metabolismo , Retina/metabolismo , Células Ganglionares da Retina/efeitos dos fármacos
7.
Invest Ophthalmol Vis Sci ; 60(6): 2049-2063, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31074760

RESUMO

Purpose: To assess the phenotypic variability and natural course of inherited retinal diseases (IRDs) caused by EYS mutations. Methods: Multiethnic cohort study (N = 30) with biallelic EYS variants from a clinical IRD database (retinitis pigmentosa [RP], N = 27; cone-rod dystrophy [CRD], N = 1; and macular dystrophy, N = 2). In vitro minigene splice assay was performed to determine the effect on EYS pre-mRNA splicing of the c.1299+5_1299+8del variant in macular dystrophy patients. Results: We found 27 different EYS variants in RP patients and 7 were novel. The rate of visual field loss of the V4e isopter area was -0.84 ± 0.44 ln(deg2) per year, and the rate of visual acuity loss was 0.75 Early Treatment Diabetic Retinopathy Study letters per year. Ellipsoid zone width was correlated with area of the hyperautofluorescent ring, with rs = 0.78 and P < 0.001. Rate of decline in ellipsoid zone width was -57 ± 17 µm per year (P < 0.01) (n = 14) or -3.69% ± 0.51% from baseline per year (P < 0.001). An isolated CRD patient carried a homozygous EYS variant (c.9405T>A), previously identified in RP patients. Two siblings with macular dystrophy carried compound heterozygous EYS variants: c.1299+5_1299+8del and c.6050G>T. The former was novel and shown to result in skipping of exon 8, and the latter was a known RP variant. Conclusions: We report on EYS-associated macular dystrophy, extending the spectrum of EYS-associated IRDs. We observed heterogeneity between RP patients in age of onset and disease progression. Identical EYS variants were found in cases with RP, CRD, and macular dystrophy. Screening for EYS variants in CRD and macular dystrophy patients might increase the diagnostic yield in previously unsolved cases.


Assuntos
Proteínas do Olho/genética , Degeneração Macular/genética , Mutação , RNA Mensageiro/genética , Retina/patologia , Retinite Pigmentosa/genética , Acuidade Visual , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise Mutacional de DNA , Eletrorretinografia , Proteínas do Olho/metabolismo , Feminino , Homozigoto , Humanos , Degeneração Macular/diagnóstico , Degeneração Macular/metabolismo , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo , Retina/metabolismo , Retina/fisiopatologia , Retinite Pigmentosa/diagnóstico , Retinite Pigmentosa/metabolismo , Tomografia de Coerência Óptica , Adulto Jovem
8.
Graefes Arch Clin Exp Ophthalmol ; 257(7): 1453-1458, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31089872

RESUMO

PURPOSE: To evaluate ophthalmological and molecular findings in eight patients with a clinical diagnosis of neurofibromatosis type 2 (NF2). New pathological mutations are described and variability in the ophthalmic phenotype and NF2 allelic heterogeneity are discussed. METHODS: Eye examination was performed in eight NF2 patients, and it included the measurement of the visual acuity, biomicroscopy, dilated fundus examination, color fundus photography, infrared photography, and spectral domain optical coherence tomography (SD-OCT). Molecular analysis was performed with whole-exome sequencing using DNA derived from peripheral blood mononuclear cells from each individual. RESULTS: Ophthalmological features were present in all patients, ranging from subtle retinal alterations identified only using SD-OCT to severe ocular damage present at birth. Six mutations were observed: two patients with stop codon mutation as shown on table 1 and result section, three patients with frameshift mutation as shown on table 1 and result section. Three novel mutations were found among them. CONCLUSIONS: It is a descriptive study of a rare disease, with poor previous literature. Clinical and genetic data are shown, reviving the need to further studies to clarify the genotype-phenotype correlations in NF2.


Assuntos
DNA/genética , Oftalmopatias/etiologia , Genes da Neurofibromatose 2/fisiologia , Mutação , Neurofibromatose 2/diagnóstico , Retina/patologia , Tomografia de Coerência Óptica/métodos , Adolescente , Adulto , Análise Mutacional de DNA , Oftalmopatias/diagnóstico , Oftalmopatias/metabolismo , Feminino , Testes Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Neurofibromatose 2/complicações , Neurofibromatose 2/genética , Fenótipo , Retina/metabolismo , Acuidade Visual , Adulto Jovem
9.
J Photochem Photobiol B ; 195: 51-57, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31082734

RESUMO

This study includes the fabrication of gold nanoparticles (AuNPs) with the help of a plant polyphenol called Resveratrol through an ecofriendly synthetic process without any use of harmful reductants. In the fabrication of AuNPs, Resveratrol acts as both stabilizing and reducing agent. The prepared AuNPs is tested on streptozotocin (STZ) induced diabetic rats for their amelioration consequence. The images of TEM displayed the development of spherical nanoparticles (NPs) with a median of 20 nm particle size. The STZ injected diabetic rats were administrated orally with calcium dobesilate (CD; 500 mg/kg/day) or AuNPs (200, 300 mg/kg/day) for a period of 3 months. The characteristics displayed by AuNPs were found to be similar with CD in decreasing permeability of blood-retinal barrier in STZ injected diabetic rats. The retinal vessels in the AuNPs administrated diabetic rats were observed to be decreased through the retinal histopathological examination. In the AuNPs administrated diabetic rats, the retinal expression of renal Pigment Epithelium-Derived Factor (PEDF) was observed to be increased and the Vascular Endothelial Growth Factor (VEGF-1), which was increased in diabetic rats was declined on treating with AuNPs. On treating the STZ injected diabetic rats with AuNPs, all the retinal mRNA expressions of VEGF-1, Tumor Necrosis Factor (TNFα), Monocyte Chemotactic Proteins-1 (MCP-1), Intercellular Adhesion Molecule-1 (ICAM-1), and Interleukin (IL)-6, IL-1ß were observed to be reduced. Furthermore, AuNPs can reduce phosphorylation of Nuclear Factor Kappa B (NF-κB) p65 and Extracellular signal Regulated Kinase (ERK) 1/2 along with a growth in nuclear translocation of pNF-κB p65 produced by STZ. To conclude, the protective effect of AuNPs on STZ injected diabetic rats could help in redeveloping the balance among the inhibitors and stimulators of angiogenesis. Furthermore, on treating with AuNPs results in inhibiting the signaling pathway of ERK1/2 as well as with amelioration of retinal inflammation through trans repression of NF-κB.


Assuntos
Retinopatia Diabética/tratamento farmacológico , Ouro/química , Nanopartículas Metálicas/química , Resveratrol/química , Animais , Glicemia/análise , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/patologia , Retinopatia Diabética/etiologia , Proteínas do Olho/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Masculino , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , NF-kappa B/metabolismo , Fatores de Crescimento Neural/metabolismo , Ratos , Ratos Wistar , Resveratrol/uso terapêutico , Retina/metabolismo , Retina/patologia , Serpinas/metabolismo , Transdução de Sinais , Estreptozocina/toxicidade , Fator A de Crescimento do Endotélio Vascular/metabolismo
10.
BMC Ophthalmol ; 19(1): 112, 2019 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-31096936

RESUMO

BACKGROUND: Oxidative stress (OS) is an essential factor in the pathogenesis of branch retinal vein occlusion (BRVO). Studies have demonstrated the role of hydrogen gas in the regulation of OS. This study was designed to evaluate the efficacy of hydrogen gas on the BRVO rat model. METHODS: Twenty-four BRVO rats were randomly divided into two groups: the hydrogen gas (H) group (42% H2, 21% O2, 37% N2) and the model (M) group (21% O2, 79% N2). Rats in the H group inhaled hydrogen gas for 8 h every day up to 30 d post-occlusion. Twelve age-matched healthy rats served as the control (C) group. Retinal function and morphology were detected at 1, 7, 14 and 30 d post-occlusion. Furthermore, the expression of vascular endothelial growth factor (VEGF-α) was detected by immunofluorescent staining. RESULTS: Full-field electroretinography (ffERG) revealed that the amplitude of the b-wave (dark-adaptation 3.0 response), the amplitude of the OPs2 wave and the light-adapted flicker response in the H group were all higher than those in the M group at 7 d post-occlusion (all p < 0.05). The reopen time of occlusive retinal vessels in the H group was 2.235 ± 1.128 d, which was shorter than that in the M group (4.234 ± 2.236 d, p < 0.05). The rats in the H group had a thinner IPL + GCL + NFL and an increased total retina compared with those in the M group at 3 d post-occlusion (p < 0.05), while the rats in the H group had a thicker INL, IPL + GCL + NFL and total retina compared with those at 7, 14 and 30 d post-occlusion (p < 0.05). Moreover, the flow velocity of ear vein blood was increased in the H group compared with that in the M group (p < 0.05). The expression of VEGF-α in the H group was dramatically decreased compared with that in the M group at 1, 7 and 14 d post-occlusion (p < 0.05), while the expression kept in similar level at 30 d post-occlusion (p > 0.05). CONCLUSIONS: Our findings demonstrate that inhalation of hydrogen gas could alleviate retinal oedema, shorten reopen time and improve retinal function, and the potential mechanism might be related to a decrease in VEGF-α expression.


Assuntos
Hidrogênio/farmacologia , Retina/efeitos dos fármacos , Oclusão da Veia Retiniana/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Modelos Animais de Doenças , Eletrorretinografia , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Retina/metabolismo , Retina/fisiopatologia , Oclusão da Veia Retiniana/fisiopatologia
11.
Cell Physiol Biochem ; 52(6): 1569-1583, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31145841

RESUMO

BACKGROUND/AIMS: Shear stress plays major roles in developmental angiogenesis, particularly in blood vessel remodeling and maturation but little is known about the shear stress sensors involved in this process. Our recent study identified endothelial Kir2.1 channels as major contributors to flow-induced vasodilation, a hallmark of the endothelial flow response. The goal of this study is to establish the role of Kir2.1 in the regulation of retinal angiogenesis. METHODS: The retina of newly born Kir2.1+/- mice were used to investigate the sprouting angiogenesis and remodeling of newly formed branched vessels. The structure, blood density and mural cell coverage have been evaluated by immunohistochemistry of the whole-mount retina. Endothelial cell alignment was assessed using CD31 staining. The experiments with flow-induced vasodilation were used to study the cerebrovascular response to flow. RESULTS: Using Kir2.1-deficient mice, we show that the retinas of Kir2.1+/- mice have higher vessel density, increased lengths and increased number of the branching points, as compared to WT littermates. In contrast, the coverage by αSMA is decreased in Kir2.1+/- mice while pericyte coverage does not change. Furthermore, to determine whether deficiency of Kir2.1 affects vessel pruning, we discriminated between intact and degraded vessels or "empty matrix sleeves" and found a significant reduction in the number of empty sleeves on the peripheral part of the retina or "angiogenic front" in Kir2.1+/- mice. We also show that Kir2.1 deficiency results in decreased endothelial alignment in retinal endothelium and impaired flow-induced vasodilation of cerebral arteries, verifying the involvement of Kir2.1 in shear-stress sensing in retina and cerebral circulation. CONCLUSION: This study shows that shear-stress sensitive Kir2.1 channels play an important role in pruning of excess vessels and vascular remodeling during retinal angiogenesis. We propose that Kir2.1 mediates the effect of shear stress on vessel maturation.


Assuntos
Neovascularização Patológica/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Estresse Mecânico , Animais , Artérias Cerebrais/metabolismo , Artérias Cerebrais/patologia , Células Endoteliais/metabolismo , Imuno-Histoquímica , Camundongos , Camundongos Mutantes , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Canais de Potássio Corretores do Fluxo de Internalização/genética , Retina/metabolismo , Retina/patologia
12.
Hum Genet ; 138(7): 723-737, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31073882

RESUMO

Strabismus refers to an abnormal alignment of the eyes leading to the loss of central binocular vision. Concomitant strabismus occurs when the angle of deviation is constant in all positions of gaze and often manifests in early childhood when it is considered to be a neurodevelopmental disorder of the visual system. As such, it is inherited as a complex genetic trait, affecting 2-4% of the population. A genome-wide association study (GWAS) for self-reported strabismus (1345 cases and 65,349 controls from UK Biobank) revealed a single genome-wide significant locus on chromosome 17q25. Approximately 20 variants across the NPLOC4-TSPAN10-PDE6G gene cluster and in almost perfect linkage disequilibrium (LD) were most strongly associated (lead variant: rs75078292, OR = 1.26, p = 2.24E-08). A recessive model provided a better fit to the data than an additive model. Association with strabismus was independent of refractive error, and the degree of association with strabismus was minimally attenuated after adjustment for amblyopia. The association with strabismus was replicated in an independent cohort of clinician-diagnosed children aged 7 years old (116 cases and 5084 controls; OR = 1.85, p = 0.009). The associated variants included 2 strong candidate causal variants predicted to have functional effects: rs6420484, which substitutes tyrosine for a conserved cysteine (C177Y) in the TSPAN10 gene, and a 4-bp deletion variant, rs397693108, predicted to cause a frameshift in TSPAN10. The population-attributable risk for the locus was approximately 8.4%, indicating an important role in conferring susceptibility to strabismus.


Assuntos
Nucleotídeo Cíclico Fosfodiesterase do Tipo 6/genética , Mutação , Proteínas Nucleares/genética , Polimorfismo de Nucleotídeo Único , Estrabismo/genética , Estrabismo/patologia , Tetraspaninas/genética , Adulto , Idoso , Animais , Estudos de Casos e Controles , Criança , Estudos de Coortes , Nucleotídeo Cíclico Fosfodiesterase do Tipo 6/metabolismo , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Família Multigênica , Proteínas Nucleares/metabolismo , Retina/metabolismo , Fatores de Risco , Estrabismo/metabolismo , Tetraspaninas/metabolismo , Acuidade Visual
13.
Nat Methods ; 16(6): 533-544, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31110282

RESUMO

Fluorescence in situ hybridization (FISH) reveals the abundance and positioning of nucleic acid sequences in fixed samples. Despite recent advances in multiplexed amplification of FISH signals, it remains challenging to achieve high levels of simultaneous amplification and sequential detection with high sampling efficiency and simple workflows. Here we introduce signal amplification by exchange reaction (SABER), which endows oligonucleotide-based FISH probes with long, single-stranded DNA concatemers that aggregate a multitude of short complementary fluorescent imager strands. We show that SABER amplified RNA and DNA FISH signals (5- to 450-fold) in fixed cells and tissues. We also applied 17 orthogonal amplifiers against chromosomal targets simultaneously and detected mRNAs with high efficiency. We then used 10-plex SABER-FISH to identify in vivo introduced enhancers with cell-type-specific activity in the mouse retina. SABER represents a simple and versatile molecular toolkit for rapid and cost-effective multiplexed imaging of nucleic acid targets.


Assuntos
DNA/análise , Corantes Fluorescentes/metabolismo , Hibridização in Situ Fluorescente/métodos , Oligonucleotídeos/química , Imagem Óptica/métodos , RNA/análise , Retina/metabolismo , Animais , Células Cultivadas , DNA/genética , DNA de Cadeia Simples/química , Humanos , Camundongos , RNA/genética , Retina/diagnóstico por imagem
14.
Invest Ophthalmol Vis Sci ; 60(5): 1328-1335, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30933260

RESUMO

Purpose: We previously reported that a specific treadmill running exercise regimen protects against light-induced retinal degeneration (LIRD) in mice. We hypothesized that this protective effect varies with running intensity. To test this, mice undergoing LIRD were run at different treadmill speeds and retinal function was assessed. Methods: BALB/c mice were assigned to LIRD groups at varying treadmill speeds-0, 5, 10, or 20 m/min labeled inactive, low, medium, and high, respectively-and compared with naïve mice exposed to standard lighting (50 lux; naïve). Following 2 weeks of exercise, a subset of mice were exposed to toxic light (10,000 lux; LIRD) for 4 hours. After 5 additional days of exercise, retinal function was assessed by ERG. Corticosterone levels in serum and cathepsin B (CTSB) protein levels in muscle, brain, serum, and retina were measured. The retinal gene expression of complement factor 1qa (C1qa) and CTSB were measured. Results: The low+LIRD and medium+LIRD exercise groups had greater a- and b-wave ERG amplitudes when compared with the inactive+LIRD group (P < 0.02). The high+LIRD mice only differed from the inactive+LIRD mice in their dark-adapted b-waves. Serum corticosterone increased in the high+LIRD mice (P < 0.006). Retinal CTSB protein levels were higher in the low+LIRD versus high+LIRD mice (P < 0.004) but were otherwise unchanged. Exercise of any intensity decreased C1qa gene expression. Conclusions: Faster running did not additionally protect against LIRD, but it did increase serum corticosterone, suggesting stress-induced limits to exercise benefits. Unexpectedly, exercise did not increase CTSB proteins levels in muscle or serum, suggesting that it may not mediate exercise effects. Our results have implications for the use of low-intensity exercise as a vision loss treatment.


Assuntos
Condicionamento Físico Animal/fisiologia , Degeneração Retiniana/fisiopatologia , Animais , Catepsina B/metabolismo , Complemento C1q/metabolismo , Corticosterona/sangue , Modelos Animais de Doenças , Eletrorretinografia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Células Fotorreceptoras de Vertebrados/fisiologia , Retina/metabolismo , Degeneração Retiniana/metabolismo
15.
Cell Mol Life Sci ; 76(18): 3657-3665, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30976840

RESUMO

D190N, a missense mutation in rhodopsin, causes photoreceptor degeneration in patients with autosomal dominant retinitis pigmentosa (adRP). Two competing hypotheses have been developed to explain why D190N rod photoreceptors degenerate: (a) defective rhodopsin trafficking prevents proteins from correctly exiting the endoplasmic reticulum, leading to their accumulation, with deleterious effects or (b) elevated mutant rhodopsin expression and unabated signaling causes excitotoxicity. A knock-in D190N mouse model was engineered to delineate the mechanism of pathogenesis. Wild type (wt) and mutant rhodopsin appeared correctly localized in rod outer segments of D190N heterozygotes. Moreover, the rhodopsin glycosylation state in the mutants appeared similar to that in wt mice. Thus, it seems plausible that the injurious effect of the heterozygous mutation is not related to mistrafficking of the protein, but rather from constitutive rhodopsin activity and a greater propensity for chromophore isomerization even in the absence of light.


Assuntos
Células Fotorreceptoras Retinianas Bastonetes/metabolismo , Retinite Pigmentosa/patologia , Rodopsina/genética , Sequência de Aminoácidos , Animais , Modelos Animais de Doenças , Eletrorretinografia , Técnicas de Introdução de Genes , Glicosilação , Camundongos , Camundongos Endogâmicos C57BL , Mutação de Sentido Incorreto , Estrutura Terciária de Proteína , Retina/metabolismo , Retina/patologia , Retinite Pigmentosa/metabolismo , Rodopsina/química , Rodopsina/metabolismo , Alinhamento de Sequência
16.
Acta Diabetol ; 56(9): 1031-1036, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30982154

RESUMO

AIMS: Retinopathy is a leading cause of vision impairment in diabetes. Its pathogenesis involves inflammation, pathological angiogenesis, neuronal and glial dysfunction. The purinergic P2X7 receptor (P2X7R) has a leading role in inflammation and angiogenesis. Potent and selective P2X7R blockers have been synthesized and tested in Phase I/II clinical studies. We hypothesize that P2X7R blockade will ameliorate diabetes-related pathological retinal changes. METHODS: Streptozotocin (STZ)-treated rats were intraperitoneally inoculated with either of two small molecule P2X7R receptor inhibitors, A740003 and AZ10606120, and after blood glucose levels increased to above 400 mg/dL, retinae were analyzed for P2X7R expression, vascular permeability, VEGF, and IL-6 expression. RESULTS: STZ administration caused a near fourfold increase in blood glucose, a large increase in retinal microvasculature permeability, as well as in retinal P2X7R, VEGF, and IL-6 expression. P2X7R blockade fully reversed retinal vascular permeability increase, VEGF accumulation, and IL-6 expression, with no effect on blood glucose. CONCLUSION: P2X7R blockade might be promising strategy for the treatment of microvascular changes observed in the early phases of diabetic retinopathy.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/tratamento farmacológico , Retinopatia Diabética/prevenção & controle , Antagonistas do Receptor Purinérgico P2X/farmacologia , Retina/efeitos dos fármacos , Animais , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 1/patologia , Retinopatia Diabética/tratamento farmacológico , Retinopatia Diabética/metabolismo , Inflamação/complicações , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Masculino , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Neuroglia/patologia , Ratos , Ratos Wistar , Receptores Purinérgicos P2X7/metabolismo , Retina/metabolismo , Retina/patologia , Estreptozocina , Resultado do Tratamento
17.
Mol Autism ; 10: 19, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31011411

RESUMO

Background: Autism spectrum disorders (ASD) affect around 1.5% of people worldwide. Symptoms start around age 2, when children fail to maintain eye contact and to develop speech and other forms of communication. Disturbances in glutamatergic and GABAergic signaling that lead to synaptic changes and alter the balance between excitation and inhibition in the developing brain are consistently found in ASD. One of the hallmarks of these disorders is hypersensitivity to sensory stimuli; however, little is known about its underlying causes. Since the retina is the part of the CNS that converts light into a neuronal signal, we set out to study how it is affected in adolescent mice prenatally exposed to valproic acid (VPA), a useful tool to study ASD endophenotypes. Methods: Pregnant female mice received VPA (600 mg/kg, ip) or saline at gestational day 11. Their male adolescent pups (P29-35) were behaviorally tested for anxiety and social interaction. Proteins known to be related with ASD were quantified and visualized in their retinas by immunoassays, and retinal function was assessed by full-field scotopic electroretinograms (ERGs). Results: Early adolescent mice prenatally exposed to VPA displayed impaired social interest and increased anxiety-like behaviors consistent with an ASD phenotype. The expression of GABA, GAD, synapsin-1, and FMRP proteins were reduced in their retinas, while mGluR5 was increased. The a-wave amplitudes of VPA-exposed were smaller than those of CTR animals, whereas the b-wave and oscillatory potentials were normal. Conclusions: This study establishes that adolescent male mice of the VPA-induced ASD model have alterations in retinal function and protein expression compatible with those found in several brain areas of other autism models. These results support the view that synaptic disturbances with excitatory/inhibitory imbalance early in life are associated with ASD and point to the retina as a window to understand their subjacent mechanisms.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Retina/metabolismo , Potenciais de Ação , Animais , Transtorno do Espectro Autista/etiologia , Transtorno do Espectro Autista/metabolismo , Endofenótipos , Feminino , Proteína do X Frágil de Retardo Mental/genética , Proteína do X Frágil de Retardo Mental/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Receptores de GABA/genética , Receptores de GABA/metabolismo , Receptores de Glutamato/genética , Receptores de Glutamato/metabolismo , Retina/fisiopatologia , Comportamento Social , Sinapsinas/genética , Sinapsinas/metabolismo , Ácido Valproico/toxicidade
18.
Phys Chem Chem Phys ; 21(18): 9450-9455, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31012470

RESUMO

Retinal proteins' biological activity is triggered by the retinal chromophore's light absorption, which initiates a photocycle. However, the mechanism by which retinal light excitation induces the protein's response is not completely understood. Recently, two new retinal proteins were discovered, namely, King Sejong 1-2 (KS1-2) and Nonlabens (Donghaeana) dokdonensis (DDR2), which exhibit H+ and Na+ pumping activities, respectively. To pinpoint whether protein conformation alterations can be achieved without light-induced retinal C13[double bond, length as m-dash]C14 double-bond isomerization, we utilized the hydroxylamine reaction, which cleaves the protonated Schiff base bond through which the retinal chromophore is covalently bound to the protein. The reaction is accelerated by light even though the cleavage is not a photochemical reaction. Therefore, the cleavage reaction may serve as a tool to detect protein conformation alterations. We discovered that in both KS1-2 and DDR2, the hydroxylamine reaction is light accelerated, even in artificial pigments derived from synthetic retinal in which the crucial C13[double bond, length as m-dash]C14 double-bond isomerization is prevented. Therefore, we propose that in both proteins the light-induced retinal charge redistribution taking place in the retinal excited state polarizes the protein, which, in turn, triggers protein conformation alterations. A further general possible application of the present finding is associated with other photoreceptor proteins having retinal or other non-retinal chromophores whose light excitation may affect the protein conformation.


Assuntos
Conformação Proteica , Retina/química , Retina/metabolismo , Rodopsinas Sensoriais/metabolismo , Hidroxilamina/química , Luz , Conformação Proteica/efeitos da radiação
19.
Eur J Pharmacol ; 853: 289-298, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30978318

RESUMO

C1q/TNF-related protein-9(CTRP9) is an adipose cytokine, a closest adiponectin paralog, which has anti-inflammatory, antioxidant, vasodilation and anti-atherosclerosis effects. In addition, it can increase insulin sensitivity, decrease blood glucose level and inhibit the apoptosis of endothelial cells. However, it remains unclear whether CTRP9 has beneficial effects on diabetic retinopathy (DR). An adenoviral vector expressing CTRP9 was intravenously injected into db/db mice, aged 12 weeks, at day 15 post injection, and the process was repeated. The transfection efficiency of CTRP9 was assessed by enzyme linked immunosorbent assay. We used RT-PCR, immunofluorescence, and Western blot to determine proinflammatory cytokines, adhesion molecules and tight-junction proteins. The breakdown of blood-retinal barrier (BRB) was evaluated using Evans blue and retinal staining. CTRP9 suppresses the expression of interleukin-1 beta, tumor necrosis factor-alpha, monocyte chemotactic protein-1 and adhesion molecules in the retina of db/db mice. CTRP9 can balance the expression of pigment epithelium-derived factor and vascular endothelial growth factor. CTRP9 can also inhibit the activation of nuclear factor Kappa B in the retina of db/db mouse. In addition, CTRP9 can prevent the breakdown of BRB and downregulation of tight-junction proteins in the retina of db/db mice. Evans blue assay revealed the breakdown of BRB and vascular leakage in the retinas of diabetic mice. CTRP9 can both qualitatively and quantitatively alleviate the vascular leakage in the early stage of diabetic retinas. CTRP9 can inhibit the inflammation of diabetic retinopathy and protect blood-retinal barrier via decreasing proinflammatory cytokines and preventing the downregulation of tight-junction proteins.


Assuntos
Adiponectina/metabolismo , Glicoproteínas/metabolismo , Retina/metabolismo , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Quimiocina CCL2/metabolismo , Inflamação/sangue , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Molécula 1 de Adesão Intercelular/metabolismo , Masculino , Camundongos , NF-kappa B/metabolismo , Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptores de Adiponectina/genética , Transcrição Genética/efeitos dos fármacos , Molécula 1 de Adesão de Célula Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
20.
Nutrients ; 11(4)2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30987058

RESUMO

Diabetic retinopathy (DR) is one of the most common complications of diabetes mellitus and is characterized by degeneration of retinal neurons and neoangiogenesis, causing a severe threat to vision. Nowadays, the principal treatment options for DR are laser photocoagulation, vitreoretinal surgery, or intravitreal injection of drugs targeting vascular endothelial growth factor. However, these treatments only act at advanced stages of DR, have short term efficacy, and cause side effects. Treatment with nutraceuticals (foods providing medical or health benefits) at early stages of DR may represent a reasonable alternative to act upstream of the disease, preventing its progression. In particular, in vitro and in vivo studies have revealed that a variety of nutraceuticals have significant antioxidant and anti-inflammatory properties that may inhibit the early diabetes-driven molecular mechanisms that induce DR, reducing both the neural and vascular damage typical of DR. Although most studies are limited to animal models and there is the problem of low bioavailability for many nutraceuticals, the use of these compounds may represent a natural alternative method to standard DR treatments.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Retinopatia Diabética/tratamento farmacológico , Suplementos Nutricionais , Retina/efeitos dos fármacos , Neovascularização Retiniana/tratamento farmacológico , Inibidores da Angiogênese/efeitos adversos , Animais , Anti-Inflamatórios/efeitos adversos , Antioxidantes/efeitos adversos , Retinopatia Diabética/metabolismo , Retinopatia Diabética/patologia , Retinopatia Diabética/fisiopatologia , Suplementos Nutricionais/efeitos adversos , Humanos , Mediadores da Inflamação/antagonistas & inibidores , Mediadores da Inflamação/metabolismo , Degeneração Neural , Estresse Oxidativo/efeitos dos fármacos , Retina/metabolismo , Retina/patologia , Retina/fisiopatologia , Neovascularização Retiniana/metabolismo , Neovascularização Retiniana/patologia , Neovascularização Retiniana/fisiopatologia , Transdução de Sinais/efeitos dos fármacos
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