Adherence to a healthy diet offers a valuable intervention to compete against the increasing cases of ocular diseases worldwide, such as dry eye disorders, myopia progression, cataracts, glaucoma, ...diabetic retinopathy, or age macular degeneration. Certain amounts of micronutrients must be daily provided for proper functioning of the visual system, such as vitamins, carotenoids, trace metals and omega-3 fatty acids. Among natural foods, the following have to be considered for boosting eye/vision health: fish, meat, eggs, nuts, legumes, citrus fruits, nuts, leafy green vegetables, orange-colored fruits/vegetables, olives-olive oil, and dairy products. Nutritional supplements have received much attention as potential tools for managing chronic-degenerative ocular diseases. A systematic search of PubMed, Web of Science, hand-searched publications and historical archives were performed by the professionals involved in this study, to include peer-reviewed articles in which natural food, nutrient content, and its potential relationship with ocular health. Five ophthalmologists and two researchers collected the characteristics, quality and suitability of the above studies. Finally, 177 publications from 1983 to 2021 were enclosed, mainly related to natural food, Mediterranean diet (MedDiet) and nutraceutic supplementation. For the first time, original studies with broccoli and tigernut (chufa de Valencia) regarding the ocular surface dysfunction, macular degeneration, diabetic retinopathy and glaucoma were enclosed. These can add value to the diet, counteract nutritional defects, and help in the early stages, as well as in the course of ophthalmic pathologies. The main purpose of this review, enclosed in the Special Issue “Health Benefits and Nutritional Quality of Fruits, Nuts and Vegetables,” is to identify directions for further research on the role of diet and nutrition in the eyes and vision, and the potential antioxidant, anti-inflammatory and neuroprotective effects of natural food (broccoli, saffron, tigernuts and walnuts), the Mediterranean Diet, and nutraceutic supplements that may supply a promising and highly affordable scenario for patients at risk of vision loss. This review work was designed and carried out by a multidisciplinary group involved in ophthalmology and ophthalmic research and especially in nutritional ophthalmology.
The Role of Autophagy in Eye Diseases Fernández-Albarral, José A; de Julián-López, Esther; Soler-Domínguez, Carmen ...
Life,
02/2021, Letnik:
11, Številka:
3
Journal Article
Recenzirano
Odprti dostop
Autophagy is a catabolic process that ensures homeostasis in the cells of our organism. It plays a crucial role in protecting eye cells against oxidative damage and external stress factors. Ocular ...pathologies of high incidence, such as age-related macular degeneration, cataracts, glaucoma, and diabetic retinopathy are of multifactorial origin and are associated with genetic, environmental factors, age, and oxidative stress, among others; the latter factor is one of the most influential in ocular diseases, directly affecting the processes of autophagy activity. Alteration of the normal functioning of autophagy processes can interrupt organelle turnover, leading to the accumulation of cellular debris and causing physiological dysfunction of the eye. The aim of this study is to review research on the role of autophagy processes in the main ocular pathologies, which have a high incidence and result in high costs for the health system. Considering the role of autophagy processes in cell homeostasis and cell viability, the control and modulation of autophagy processes in ocular pathologies could constitute a new therapeutic approach.
Preclinical Alzheimer’s disease (AD) includes cognitively healthy subjects with at least one positive biomarker: reduction in cerebrospinal fluid Aβ42 or visualization of cerebral amyloidosis by ...positron emission tomography imaging. The use of these biomarkers is expensive, invasive, and not always possible. It has been shown that the retinal changes measured by optical coherence tomography (OCT) and OCT-angiography (OCTA) could be biomarkers of AD. Diagnosis in early stages before irreversible AD neurological damage takes place is important for the development of new therapeutic interventions. In this review, we summarize the findings of different published studies using OCT and OCTA in participants with preclinical AD. To date, there have been few studies on this topic and they are methodologically very dissimilar. Moreover, these include only two longitudinal studies. For these reasons, it would be interesting to unify the methodology, make the inclusion criteria more rigorous, and conduct longer longitudinal studies to assess the evolution of these subjects. If the results were consistent across repeated studies with the same methodology, this could provide us with insight into the value of the retinal changes observed by OCT/OCTA as potential reliable, cost-effective, and noninvasive biomarkers of preclinical AD.
In this case control study, we examined the retinal thickness of the different layers in the macular region and peripapillary retinal nerve fiber layer (RNFL) with optical coherence tomography (OCT) ...in healthy cognitive subjects (from 51 to 74 years old) at high genetic risk for developing Alzheimer’s disease (AD). Thirty-five subjects with a family history of Alzheimer disease (AD) (FH+) and ApoE ɛ4 carriers and 29 age-matched control subjects without a family history of AD (FH−) and ApoE ɛ4 non-carriers were included. Compared to FH− ApoE ɛ4 non-carriers, in FH+ ApoE ɛ4 carriers, there were statistically significant decreases (p < 0.05) in (i) the foveal area of mRNFL; (ii) the inferior and nasal sectors in the outer and inner macular ring in the inner plexiform layer (IPL); (iii) the foveal area and the inferior sector in the outer macular ring in the inner nuclear layer (INL); and (iv) the inferior sector of the outer macular ring in the outer plexiform layer (OPL). However, no statistically significant differences were found in the peripapillary thickness of RNFL between both study groups. In subjects with cognitive health and high genetic risk for the development of AD, initial changes appeared in the macular area. OCT could be a promising, cost-effective and non-invasive test useful in early AD, before the onset of clinical symptoms.
Microglial activation is associated with glaucoma. In the model of unilateral laser-induced ocular hypertension (OHT), the time point at which the inflammatory process peaks remains unknown. ...Different time points (1, 3, 5, 8, and 15 d) were compared to analyze signs of microglial activation both in OHT and contralateral eyes. In both eyes, microglial activation was detected in all retinal layers at all time points analyzed, including: i) increase in the cell number in the outer segment photoreceptor layer and plexiform layers (only in OHT eyes) from 3 d onward; ii) increase in soma size from 1 d onward; iii) retraction of the processes from 1 d in OHT eyes and 3 d in contralateral eyes; iv) increase in the area of the retina occupied by Iba-1+ cells in the nerve fiber layer/ganglion cell layer from 1 d onward; v) increase in the number of vertical processes from 1 d in contralateral eyes and 3 d in OHT eyes. In OHT eyes at 24 h and 15 d, most Iba-1+ cells were P2RY12+ and were down-regulated at 3 and 5 d. In both eyes, microglial activation was stronger at 3 and 5 d (inflammation peaked in this model). These time points could be useful to identify factors implicated in the inflammatory process.
Glaucoma is a neurodegenerative disease that leads to the loss of retinal ganglion cells (RGC) and thus to blindness. There are numerous experimental models used for the study of this pathology. ...Among the different models, episcleral vein photocoagulation is one of the most widely used. In this model there is a transient increase in intraocular pressure that returns to normal values about 7 days after induction of ocular hypertension (OHT). In addition, typical glaucoma changes, such as loss of RGC, thinning of the optic nerve fiber layer, and glial activation, occur in this model. All these changes have been described in detail over time after OHT induction. In this chapter, we describe the detailed method of OHT induction in Swiss albino mice by diode laser photocoagulation of limbal and episcleral veins.
Alzheimer’s disease (AD) may manifest retinal changes preceding brain pathology. A transversal case-control study utilized spectral-domain OCT angiography (SD-OCTA) and Angio-Tool software 0.6a to ...assess retinal vascular structures and OCT for inner and outer retina thickness in the APPNL-F/NL-F AD model at 6, 9, 12, 15, 17, and 20 months old. Comparisons to age-matched wild type (WT) were performed. The analysis focused on the three vascular plexuses using AngiooTool and on retinal thickness, which was represented with the Early Treatment Diabetic Retinopathy Study (ETDRS) sectors. Compared to WT, the APPNL-F/NL-F group exhibited both vascular and structural changes as early as 6 months persisting and evolving at 15, 17, and 20 months. Significant vascular alterations, principally in the superficial vascular complex (SVC), were observed. There was a significant decrease in the vessel area and the total vessel length in SVC, intermediate, and deep capillary plexus. The inner retina in the APPNL-F/NL-F group predominantly decreased in thickness while the outer retina showed increased thickness in most analyzed time points compared to the control group. There are early vascular and structural retinal changes that precede the cognitive changes, which appear at later stages. Therefore, the natural history of the APPNL-F/NL-F model may be more similar to human AD than other transgenic models.
Aims/Purpose: The use of murine models of Alzheimer's disease (AD) in the study of its pathophysiology is essential. In addition to a histological study of the retina, optical coherence tomography ...(OCT) allows a cost‐effective in vivo analysis of the retina. However, there is no standardization in the use of OCT in murine models of AD, leading to significant variations in study results. A review of the literature on murine models of AD analysed by OCT has been carried out. The characteristics of the animal model, the types of OCT, the retinal sectors analysed, the segmentation layers and the software used for segmentation were examined.
Methods: We performed a literature search up to April 2023 using “MESH” terms in PubMed. The terms used were: “Alzheimer's mouse model”, “Optical Coherence Tomography”, “retinal optical coherence tomography” … as well as their combinations. We filter the articles by author criteria: the terms had to be in the title, in the or in the article and they should be written in English or Spanish. Finally, 76 articles were used to the manuscript.
Results: In comparison to studies using OCT in AD patients, only fourteen studies have utilized this technique to examine the retinas of murine AD models. Six different models, both first and second generation, were analysed, with most featuring presenilin mutations. There is no consensus regarding the measuring instrument, retinal area analysed, segmentation techniques, or software employed for analysis. Although some authors used the same OCT device, variations in other parameters hinder direct result comparison.
Conclusions: It is essential to establish a unified criteria for OCT analysis of the retina in murine models of AD. This would allow the comparison of results and the establishment of measurement protocols. The use of OCT to understand the pathophysiology of AD would facilitate the longitudinal analysis of the disease and the possible identification of biomarkers.
Aims/Purpose: The progression of Alzheimer's disease (AD) manifests from a preclinical stage, characterized by asymptomatic pathological alterations, to an advanced stage of AD accompanied by ...cognitive impairment. The aim of this study was to explore visual function along the entire AD continuum, from individuals with a high genetic predisposition to those in the moderate phase of the disease.
Methods: All participants underwent a visual examination and had to be visually healthy to be included. The study contained five groups: controls (n = 53), individuals with a positive family history of AD (HF+) (n = 13), mild cognitive impairment (MCI) (n = 23), mild AD (n = 25) and moderate AD (n = 21). The study analysed the results of errors in colour perception.
Results: A significant increase in the total number of errors was observed between the control group and the moderate AD group. And also when comparing the FH+ group with the MCI group, the mild AD group and the moderate AD group. Significant differences were found on the tritan axis between the control group and the mild AD group, as well as in the moderate AD group. Significant differences were observed between the FH+ group and the mild AD group, as well as in the moderate AD group. A significant increase in the number of errors on the deutan axis was observed between the control group and both the mild and moderate AD groups. In addition, a statistically significant increase was observed when comparing the FH+ group with the moderate AD group. The test correlated with the MMSE score and also showed good predictive value when memory impairment was present.
Conclusions: Understanding the importance of changes in colour perception in AD continuum can aid in the early detection and treatment of AD, potentially improving patient outcomes and facilitating targeted interventions.
Aims/Purpose: Alzheimer's disease (AD) is a degenerative neurological disorder characterized by the progressive loss of neurons and their synapses in the brain. Similar alterations have been observed ...in the retina even before they manifest in the brain. The retina has been proposed as a readily accessible biomarker for AD. In a previous work utilizing a murine model of AD (APPNL‐F/NL‐F), changes in retinal thickness, as measured by optical coherence tomography (OCT), were observed at 15 and 17 months. The objective of this study was to quantitatively assess the population of retinal ganglion cells (RGCs) in this same AD murine model over a specified time period and compare it with wild‐type (WT) mice.
Methods: To quantitatively assess the population of retinal ganglion cells we used two study groups: the APPNL‐F/NL‐F model throughout the time period of (6, 9, 12, 17, and 20 months) and compared with wild‐type (WT) mice age matched (n = 30 in both groups). The quantification of retinal ganglion cells (RGCs) was conducted using immunohistochemical analysis with the Brn3a marker. This analysis was performed using a semi‐automatic algorithm implemented in the MatLab environment, which was developed by the Ramón Castroviejo Institute for Ophthalmic Research. For the analysis, the entire retina was considered and segmented into the peripapillary, intermediate, and peripheral zones.
Results: A statistically significant decresase (p < 0.05) in the population of Brn3a + cells was observed in the APPNL‐F/NL‐F group compared to the WT group. This decreased was found in the total retina at 12 months, in the peripapillary zone at 9, 12, and 20 months, and in the intermediate zone at 12 months of the study.
Conclusions: The APPNL‐F/NL‐F mouse model exhibits RGCs loss at 9, 12, and 20 months, mirroring the patterns observed in human cases. These findings suggest that the model holds promise for investigating and studying mechanisms related to RGC degeneration in Alzheimer's disease.
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