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1.
Int J Ophthalmol ; 17(9): 1723-1730, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39296574

RESUMEN

AIM: To assess the causal link between 211 gut microbiota (GM) taxa and dry age-related macular degeneration (dAMD) risk. METHODS: Mendelian randomization using instrumental factors taken from a genome-wide association study (GWAS) were used. Inverse variance weighted (IVW) analysis and sensitivity analysis were performed on the FinnGen project, which included 5095 cases and 222 590 controls. RESULTS: The IVW analysis showed substantial genus- and family-level relationships between GM taxa and dAMD risk. Specifically, the family Peptococcaceae (P=0.03), genus Bilophila (P=3.91×10-3), genus Faecalibacterium (P=6.55×10-3), and genus Roseburia (P=0.04) were linked to a higher risk of developing dAMD, while the genus Candidatus Soleaferrea (P=7.75×10-4), genus Desulfovibrio (P=0.04) and genus Eubacterium ventriosum group (P=0.04) exhibited a protective effect against dAMD. No significant causal relationships were observed at higher taxonomic levels. Additionally, in the reverse IVW analysis, no meaningful causal effects of the 7 GM taxa. CONCLUSION: These findings give support for the gut-retina axis participation in dAMD and shed light on putative underlying processes. Investigations on the connection between GM and dAMD have not yet revealed the underlying mechanism.

2.
Adv Healthc Mater ; : e2401613, 2024 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-39129350

RESUMEN

Ferrous ion accumulation and lethal oxidative stress mediate irreversible retinal pigment epithelial (RPE) cell ferroptosis and subsequent photoreceptor degeneration, a potential key pathogenic factor in the onset of dry age-related macular degeneration (dAMD), causing irreversible vision loss in the global elderly population. However, currently, no effective interventional treatment strategy exists in clinical practice. Herein, lesion site-targeted melanin-like nanoparticles, named ConA-MelNPs, are designed as a novel ferroptosis inhibitor for retinal degenerative diseases. ConA-MelNPs possessed chelating iron ion characteristics, alleviating severe mitochondrial damage caused by oxidative stress and protecting RPE cells from ferroptosis induced by sodium iodate (NaIO3). In a preclinical dAMD mouse model, a single intravitreal injection of ConA-MelNPs yielded significant responses in electroretinograms and visually-driven optomotor responses in visually impaired mice, resisting the challenge posed by secondary NaIO3-induced injuries, with the long-term sustainability of its therapeutic effect. Mechanistically, ConA-MelNPs achieve a therapeutic effect by interrupting the detrimental cascade involving "RPE cell ferroptosis, lethal oxidative stress, and microglial proinflammatory activation," affording the restoration of retinal homeostasis. The synthesized ConA-MelNPs demonstrated good biosafety, with no detected ophthalmic or systemic side effects. Collectively, ConA-MelNPs are proposed as a promising therapeutic option for atrophic retinal diseases such as dAMD.

3.
Antioxidants (Basel) ; 13(6)2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38929085

RESUMEN

This study aims to investigate the role of microRNA let-7f in the dysfunction and degeneration of retinal pigment epithelium (RPE) cells through the induction of senescence and oxidative stress. Furthermore, we explore whether let-7f inhibition can protect these cells against sodium iodate (SI)-induced oxidative stress. Oxidative stress and let-7f expression are reciprocally regulated in retinal pigment epithelial cells. Overexpression of let-7f in ARPE-19 cells induced oxidative stress as demonstrated by increased reactive oxygen species (ROS) production as well as senescence. Inhibition of let-7f successfully protected RPE cells from the detrimental effects induced by SI. In addition, let-7f overexpression induced RPE cellular dysfunction by diminishing their migratory capabilities and reducing the phagocytosis of porcine photoreceptor outer segments (POS). Results were further confirmed in vivo by intravitreal injections of SI and let-7f antagomir in C57BL/6 mice. Our results provide strong evidence that let-7f is implicated in the dysfunction of RPE cells through the induction of senescence and oxidative injury. These findings may help to uncover novel and relevant processes in the pathogenesis of dry AMD.

4.
J Pers Med ; 14(5)2024 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-38793125

RESUMEN

In this longitudinal retrospective image analysis, conducted on patients diagnosed with dry age-related macular degeneration (AMD) and 5 years of follow-up imaging data, the study aimed to investigate the relationship between ellipsoid zone (EZ) integrity on spectral domain optical coherence tomography (SD-OCT) and visual acuity (VA). Using a machine learning-enabled feature extraction tool, quantitative EZ parameters were derived from SD-OCT images. The analysis revealed significant correlations between EZ integrity metrics and VA. Eyes with excellent VA (≥20/25 Snellen) exhibited higher EZ integrity, including less EZ attenuation, thicker ellipsoid zone-retinal pigment epithelium (EZ-RPE) thickness, and higher EZ intensity, in contrast to eyes with worse VA (≤20/40 Snellen). Additionally, eyes with geographic atrophy (GA) in the foveal region displayed compromised EZ integrity compared to those without GA. Notably, baseline EZ integrity metrics were predictive of future VA loss. These findings suggest that quantitative SD-OCT measurements of EZ integrity could potentially detect early changes in dry AMD and serve as valuable indicators for predicting future functional outcomes. Furthermore, these measurements hold promise for use in clinical trial screenings, offering insights into the progression of the disease and its impact on visual acuity. This study underscores the importance of EZ integrity assessment in understanding and managing dry AMD.

5.
Exp Eye Res ; 242: 109889, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38593971

RESUMEN

Dry age-related macular degeneration (AMD) is a prevalent clinical condition that leads to permanent damage to central vision and poses a significant threat to patients' visual health. Although the pathogenesis of dry AMD remains unclear, there is consensus on the role of retinal pigment epithelium (RPE) damage. Oxidative stress and chronic inflammation are major contributors to RPE cell damage, and the NOD-like receptor thermoprotein structural domain-associated protein 3 (NLRP3) inflammasome mediates the inflammatory response leading to apoptosis in RPE cells. Furthermore, lipofuscin accumulation results in oxidative stress, NLRP3 activation, and the development of vitelliform lesions, a hallmark of dry AMD, all of which may contribute to RPE dysfunction. The process of autophagy, involving the encapsulation, recognition, and transport of accumulated proteins and dead cells to the lysosome for degradation, is recognized as a significant pathway for cellular self-protection and homeostasis maintenance. Recently, RPE cell autophagy has been discovered to be closely linked to the development of macular degeneration, positioning autophagy as a cutting-edge research area in the realm of dry AMD. In this review, we present an overview of how lipofuscin, oxidative stress, and the NLRP3 inflammasome damage the RPE through their respective causal mechanisms. We summarized the connection between autophagy, oxidative stress, and NLRP3 inflammatory cytokines. Our findings suggest that targeting autophagy improves RPE function and sustains visual health, offering new perspectives for understanding the pathogenesis and clinical management of dry AMD.


Asunto(s)
Autofagia , Estrés Oxidativo , Epitelio Pigmentado de la Retina , Humanos , Epitelio Pigmentado de la Retina/metabolismo , Epitelio Pigmentado de la Retina/patología , Autofagia/fisiología , Estrés Oxidativo/fisiología , Inflamasomas/metabolismo , Lipofuscina/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Atrofia Geográfica/metabolismo , Atrofia Geográfica/patología
7.
Exp Eye Res ; 240: 109823, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38331017

RESUMEN

Age-related macular degeneration (AMD) is a major cause of blindness in the elderly worldwide. Multiple studies have shown that epithelial-mesenchymal transition (EMT) plays a pivotal role in the pathogenesis of AMD. Isorhamnetin (Isor) is a flavonoid compound that inhibits EMT in tumor cells. However, whether it can also attenuate EMT in the retinal pigment epithelium (RPE) is unknown. Therefore, our study was designed to probe the possible impact of Isor on EMT process in both mouse retina and ARPE-19 cells. C57BL/6 mice were utilized to establish a dry AMD model. Isor and LCZ (a mixture of luteine/ß-carotene/zinc gluconate) were administered orally for 3 months. The effects of Isor on the retina were evaluated using fundus autofluorescence, optical coherence tomography, and transmission electron microscopy. Transwell and wound healing assay were employed to assess ARPE-19 cell migration. Western blotting and immunofluorescence were used to measure the protein expressions associated with EMT, Nrf2 and AKT/GSK-3ß pathway. The findings indicated that Isor alleviated dry AMD-like pathological changes in vehicle mice retina, inhibited the migration of Ox-LDL-treated ARPE-19 cells, and repressed the EMT processes in vivo and in vitro. Furthermore, Isor activated Nrf2 pathway and deactivated AKT/GSK-3ß pathway in both vehicle mice and ARPE-19 cells. Interestingly, when Nrf2 siRNA was transfected into ARPE-19 cells, the inhibitory effect of Isor on EMT and AKT/GSK-3ß pathway was attenuated. These results suggested that Isor inhibited EMT processes via Nrf2-dependent AKT/GSK-3ß pathway and is a promising candidate for dry AMD treatment.


Asunto(s)
Proteínas Proto-Oncogénicas c-akt , Quercetina/análogos & derivados , Transducción de Señal , Humanos , Ratones , Animales , Anciano , Proteínas Proto-Oncogénicas c-akt/metabolismo , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Epitelio Pigmentado de la Retina/metabolismo , Ratones Endogámicos C57BL , Línea Celular Tumoral , Transición Epitelial-Mesenquimal
8.
Cureus ; 16(1): e51935, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38333436

RESUMEN

INTRODUCTION: To date few studies have investigated the correlation between inflammatory markers and lipoproteins in the serum of age-related macular degeneration (AMD) patients, often reporting conflicting findings. This study aimed to investigate the correlation between lipid analytes and C-reactive protein (CRP) levels in individuals diagnosed with dry AMD. METHODS: A standard clinical lipid panel (total cholesterol, triglycerides, high-density lipoprotein [HDL], and low-density lipoproteins) and CRP laboratory results were retrospectively collected from the medical records of patients with dry AMD and age- and sex-matched controls. RESULTS: The study included 90 patients with dry AMD and 270 patients without AMD. In univariate analysis, CRP showed a higher mean value in cases than in controls. After adjusting for age and sex, CRP and triglyceride levels showed significant differences between cases and controls. Pearson's correlation analysis revealed a significant negative correlation between CRP and HDL levels in the dry AMD group (n=90). Other lipid analytes showed no significant correlations with CRP. CONCLUSION: Our findings add to the growing body of evidence linking inflammation to AMD. Although it is unclear whether changes in serum CRP and triglyceride levels are the causes or effects, monitoring both analytes may be beneficial as an early disease predictor, especially in individuals with a family history of AMD. The negative correlation between CRP and HDL (i.e., inflammation and good cholesterol) may be targeted for future therapies.

9.
International Eye Science ; (12): 1032-1037, 2024.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1032343

RESUMEN

AIM: To investigate the protective effect of Jianpi Bushen Yishi Formula on dry age-related macular degeneration(dARMD)induced by sodium iodate in mice and its mechanism.METHODS: A total of 27 SPF male C57BL/6 mice were randomly divided into blank, model and traditional Chinese medicine groups, with 9 in each group, the structure and morphology of the retina were observed by Hematoxylin-Ehong(HE)staining, and the intracellular reactive oxygen species(ROS)in the retina were observed by fluorescence staining with dihydroethidium(DHE). In addition, malondialdehyde(MDA)and superoxide dismutase(SOD)expression levels in mouse retina were detected by biochemical kit, and expression levels of silent information regulator type 1(SIRT1)and peroxisome proliferator-activated receptor-γ coactivator 1-α(PGC-1α)protein in mouse retina were detected by Western blot.RESULTS: Retinal structure and morphology of the model group showed a slight or mild decrease in the number of cells in the outer nuclear layer, a localized thinning of the outer nuclear layer, an inconspicuous demarcation between the outer and outer membranes, a slight or mild swelling of retinal pigment epithelial cells, and a slight or mild disturbance in the arrangement of retinal cells; while retinal pigment epithelial cells and photoreceptor layers in the traditional Chinese medicine group were significantly improved. DHE staining fluorescence results showed that the ROS level in the model group was significantly higher than that in the blank group at 14 d after modeling(P<0.01); the ROS level in the traditional Chinese medicine group was significantly lower than that in the model group(P<0.001). ELISA showed that the SOD level of the model group was significantly lower than that of the blank group at 14 d after modeling(P<0.01), and the MDA level was significantly increased(P<0.01)in the model group compared with the blank group; the SOD level was significantly higher(P<0.01), and the MDA level was significantly lower(P<0.01)in the traditional Chinese medicine group compared with the model group. Western blot results showed that the expression of SIRT1 and PGC-1α in the model group was significantly lower compared with that in the blank group(P<0.01), and the expression of SIRT1 and PGC-1α in the traditional Chinese medicine group was significantly higher compared with that in the model group at 7 and 14 d after modeling(P<0.01).CONCLUSION: The Chinese herbal medicine, which strengthens the spleen, tonifies the kidney and benefits the eyesight, can improve the oxidative stress state of the retina induced by sodium iodate in mice and reduce the damage to the retinal tissues, which may exert the anti-oxidative stress effect through the PGC-1α/SIRT1 signaling pathway.

10.
International Eye Science ; (12): 1240-1245, 2024.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1038537

RESUMEN

Age-related macular degeneration(ARMD)is one of the leading causes of irreversible blindness in the elderly. Anti-vascular endothelial growth factor(VEGF)drugs have become the first-line treatment for neovascular ARMD, which has greatly changed the prognosis. However, dry ARMD still lacks effective treatment means, focusing on prevention. At present, several clinical treatment methods are being explored, including antioxidant therapy, complement therapy, neuroprotective therapy, gene therapy, etc. This review mainly summarizes the existing clinical trials and their progress on the treatment of dry ARMD, in order to provide future prospects for the treatment of dry ARMD. A number of clinical trials have already produced promising results for the treatment of dry ARMD, and it is believed that more and more clinical trials will be successful in the near future to provide more effective treatments for patients with dry ARMD.

11.
Biomaterials ; 305: 122429, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38150770

RESUMEN

In clinics, therapeutic proteins are commonly used to treat retinal diseases through intraocular injection, the treatment which suffers from rather low patient compliance. Topical administration (e.g. eye-drops) of large molecule drugs remains a major challenge due to the presence of various barriers in the eye. In this study, zwitterion-grafted chitosan (CS-ZW) was developed and then self-assembled with protein therapeutics including adalimumab (ADA) or catalase (CAT) for the treatment of dry age-related macular degeneration (dAMD) via topical eyedrops. Since CS-ZW can cross the mucus layer and open the tight junctions between epithelial cells, their delivered therapeutic proteins can be shuttled across the ocular barriers to reach the diseased site in the fundus. CS-ZW/ADA eyedrops delivering ADA to bind TNF-α in the fundus achieved a similar therapeutic effect to intravitreal ADA injection in a mouse dAMD model. In addition, the therapeutic effect was further improved by combining eyedrop formulations of CS-ZW/ADA and CS-ZW/CAT, the latter of which can clear reactive oxygen species (ROS) in the lesion to further assist dAMD treatment. Our work provides a simple and effective delivery vehicle that can non-invasively treat fundus diseases such as dAMD, showing potential advantages in reducing side effects associated with intraocular injection and improving patient compliance.


Asunto(s)
Oftalmopatías , Degeneración Macular , Animales , Ratones , Humanos , Soluciones Oftálmicas/uso terapéutico , Polímeros , Ojo , Degeneración Macular/tratamiento farmacológico , Sistemas de Liberación de Medicamentos
12.
Int Ophthalmol ; 43(12): 4869-4878, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37936001

RESUMEN

BACKGROUND: Age-related macular degeneration (AMD) is the leading cause of blindness in the elderly population, and Dry AMD is the most common clinical subtype. However, effective measures for the early diagnosis and treatment of dry AMD have not been proposed. In recent years, NOD-like receptors (NLRs) have received attention in the study of AMD as an important class of pattern recognition receptors. We attempted to elucidate the pathogenesis of NLRs in dry AMD from the perspective of chronic inflammation. METHODS: This study involved 13 patients with dry AMD, 10 age- and sex-matched normal population without any history of disease and 8 patients with wet AMD as controls. Using RT-qPCR, the mRNA expression levels of NLRs in peripheral blood peripheral blood mononuclear cells (PBMCs) were compared to analyze the statistical differences in the expression contents among the three populations. RESULTS: The relative RNA expression of nucleotide-binding oligomerization-like receptor protein 12 (NLRP12) with negative regulation of inflammation was significantly lower in dry AMD patients than in normal people and wet AMD patients. And NLRX1, which also has an anti-inflammatory effect, was lower in dry AMD patients than in wet AMD patients. However, NLRP3 with proinflammatory effect was significantly expressed in wet AMD. CONCLUSION: The significant decrease in NLRP12 in dry AMD may become a breakthrough in the study of dry AMD and systemic chronic inflammatory response. However, NLRP3 may have a more important role in wet AMD.


Asunto(s)
Atrofia Geográfica , Proteína con Dominio Pirina 3 de la Familia NLR , Degeneración Macular Húmeda , Anciano , Humanos , Atrofia Geográfica/diagnóstico , Inflamación , Leucocitos Mononucleares , Proteínas Mitocondriales , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Degeneración Macular Húmeda/diagnóstico , Degeneración Macular Húmeda/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo
13.
Eur J Ophthalmol ; : 11206721231204383, 2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37787166

RESUMEN

PURPOSE: To report the emergence and progress of four late-stage characteristics: incomplete retinal pigment epithelium and outer retinal atrophy (iRORA) and complete RPE and outer retinal atrophy (cRORA), drusen ooze and drusen collapse in eyes with dry age-related macular degeneration (AMD) using Spectral Domain Optical Coherence Tomography (SD-OCT). METHODS: This was a retrospective analysis of eyes with non-exudative AMD. Multimodal imaging was done at follow up visits ≤ 12 months. OCT volume scan was used to assess and identify the 4 characteristics. Univariate analysis was done for the various demographic and clinical characteristics.Patients with a mean age of 76.7 ± 10 years were followed up for 69.9 ± 20.6 months. iRORA, cRORA, drusen ooze was present in 15.6%, 15.6% and 15.6% of patients at baseline, respectively, and 25.0%, 40.6% and 53.1% of patients at the final follow-up, respectively. At baseline 9.1%, 0% and 9.1% of patients had bilateral drusen ooze, iRORA and cRORA, respectively. By the final follow-up, drusen collapse occurred in 46.9% and 18.8% patients in unilateral and bilateral eyes, respectively.For bilateral cases, the mean interval of time between emergence inthe two eyes for drusen ooze, drusen collapse, iRORA, and cRORA was 5 ± 1.4 years, 2.2 ± 2.2 years, 3.5 ± 0.7 and 1.7 ± 0.6 years, respectively. CONCLUSIONS: Late-stage OCT biomarkers are seen bilaterally at 21.9% at baseline and at 56.3% at 5.8 years follow-up. Once present in one eye, cRORA had the shortest mean interval before appearance in the other eye.

14.
Clin Exp Ophthalmol ; 51(8): 835-852, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37737509

RESUMEN

Age-related macular degeneration is a global disease with a significant societal impact. The advent of anti-vascular endothelial growth factor therapy (anti-VEGF) has revolutionised the treatment of neovascular age-related macular degeneration (nAMD). Dry age-related macular degeneration (dAMD) is being investigated for possible therapeutic options. The therapeutic categories undergoing clinical trials include complement pathway inhibitors, visual cycle modulators, reduction of toxic byproducts, antioxidative therapy, neuroprotective agents, laser therapy, surgical options, gene therapy, stem cell therapy, and miscellaneous treatments. Two intravitreal anti-complement factors (pegcetacoplan and avacincaptad pegol) have recently shown phase 3 clinical trial evidence of a reduction in the growth of geographic atrophy. In this review, we provide an update on treatment options currently undergoing clinical research trials for the management of dAMD and preventing the progression of Geographic Atrophy (GA).


Asunto(s)
Atrofia Geográfica , Degeneración Macular , Degeneración Macular Húmeda , Humanos , Atrofia Geográfica/terapia , Degeneración Macular/tratamiento farmacológico , Inhibidores de la Angiogénesis/uso terapéutico , Inyecciones Intravítreas , Degeneración Macular Húmeda/tratamiento farmacológico
15.
Photodiagnosis Photodyn Ther ; 42: 103629, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37244451

RESUMEN

BACKGROUND: Dry Age-related macular degeneration (AMD), which affects the older population, can lead to blindness when left untreated. Preventing vision loss in elderly needs early identification. Dry-AMD diagnosis is still time-consuming and very subjective, depending on the ophthalmologist. Setting up a thorough eye-screening system to find Dry-AMD is a very difficult task. METHODOLOGY: This study aims to develop a weighted majority voting (WMV) ensemble-based prediction model to diagnose Dry-AMD. The WMV approach combines the predictions from base-classifiers and chooses the class with greatest vote based on assigned weights to each classifier. A novel feature extraction method is used along the retinal pigment epithelium (RPE) layer, with the number of windows calculated for each picture playing an important part in identifying Dry-AMD/normal images using the WMV methodology. Pre-processing using hybrid-median filter followed by scale-invariant feature transform based segmentation of RPE layer and curvature flattening of retina is employed to measure exact thickness of RPE layer. RESULT: The proposed model is trained on 70% of the OCT image database (OCTID) and evaluated on remaining OCTID and SD-OCT Noor dataset. Model has achieved accuracy of 96.15% and 96.94%, respectively. The suggested algorithm's effectiveness in Dry-AMD identification is demonstrated by comparison with alternative approaches. Even though the suggested model is only trained on the OCTID, it has performed well when tested on additional dataset. CONCLUSION: The suggested architecture can be used for quick eye-screening for early identification of Dry-AMD. The recommended method may be applied in real-time since it requires fewer complexity and learning-variables.


Asunto(s)
Degeneración Macular , Fotoquimioterapia , Humanos , Anciano , Degeneración Macular/diagnóstico por imagen , Tomografía de Coherencia Óptica/métodos , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes , Retina
16.
Int J Mol Sci ; 24(7)2023 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-37047224

RESUMEN

There is a large unmet medical need to develop disease-modifying treatment options for individuals with age-related degenerative diseases of the central nervous system. The sigma-2 receptor (S2R), encoded by TMEM97, is expressed in brain and retinal cells, and regulates cell functions via its co-receptor progesterone receptor membrane component 1 (PGRMC1), and through other protein-protein interactions. Studies describing functions of S2R involve the manipulation of expression or pharmacological modulation using exogenous small-molecule ligands. These studies demonstrate that S2R modulates key pathways involved in age-related diseases including autophagy, trafficking, oxidative stress, and amyloid-ß and α-synuclein toxicity. Furthermore, S2R modulation can ameliorate functional deficits in cell-based and animal models of disease. This review summarizes the current evidence-based understanding of S2R biology and function, and its potential as a therapeutic target for age-related degenerative diseases of the central nervous system, including Alzheimer's disease, α-synucleinopathies, and dry age-related macular degeneration.


Asunto(s)
Enfermedad de Alzheimer , Enfermedad por Cuerpos de Lewy , Receptores sigma , Animales , Enfermedad de Alzheimer/tratamiento farmacológico , Receptores sigma/metabolismo , alfa-Sinucleína/metabolismo , Péptidos beta-Amiloides , Biología
17.
J Control Release ; 357: 356-370, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37028452

RESUMEN

Oxidative stress-induced retinal pigment epithelial (RPE) cell damage is a major factor in the pathogenesis of dry age-related macular degeneration (AMD). Although the therapeutic effect of mesenchymal stem cell (MSC) exosomes on dry AMD has been preliminarily discussed, the underlying mechanism has yet to be reported. Here, we demonstrate that MSC exosomes, acting as a nanodrug, can effectively reduce the incidence of dry AMD by regulating Nrf2/Keap1 signaling pathway. In the in vitro study, MSC exosomes relieved the damage of ARPE-19 cells, suppressed the activity of lactate dehydrogenase (LDH), decreased the level of reactive oxygen species (ROS) and upregulated the activity of superoxide dismutase (SOD). In the in vivo study, MSC exosomes were administered via intravitreal injection. MSC exosomes effectively protected RPE layer, photoreceptor outer segment/inner segment (OS/IS) layer and outer nuclear layer (ONL) from NaIO3-induced damage. Western blotting results showed that the ratio of Bcl-2/Bax was increased after pre-administration of MSC exosomes in both in vitro and in vivo studies. Moreover, MSC exosomes were found to upregulate the expressions of Nrf2, P-Nrf2, Keap1 and HO-1, while the antioxidant effect of MSC exosomes was blocked by ML385 (a Nrf2 inhibitor). Besides, immunofluorescence results showed that MSC exosomes upregulated the expression of P-Nrf2 in the nucleus compared to the oxidant group. These results indicate that MSC exosomes protect RPE cells from oxidative damage by regulating Nrf2/Kepa1 signaling pathway. In conclusion, MSC exosomes are promising nanotherapeutics for the treatment of dry AMD.


Asunto(s)
Exosomas , Degeneración Macular , Células Madre Mesenquimatosas , Humanos , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/farmacología , Factor 2 Relacionado con NF-E2/uso terapéutico , Exosomas/metabolismo , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Degeneración Macular/tratamiento farmacológico , Células Madre Mesenquimatosas/metabolismo , Epitelio Pigmentado de la Retina
18.
J Photochem Photobiol B ; 240: 112654, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36724628

RESUMEN

Long-term light exposure, especially in the spectrum of blue light, frequently causes excessive oxidative stress in dry age-related macular degeneration (AMD). Here, to gain insight into the underlying mechanism, we focused on mitochondrial dynamics alterations under long-term exposure to blue light in mouse and retinal cells. Six-month-old C57BL/6 mice were exposed to blue light (450 nm, 800 lx) for 2 weeks. The phenotypic changes in the retina were assayed using haematoxylin-eosin staining and transmission electron microscopy. Long-term blue light exposure significantly thinned each retinal layer in mice, induced retinal apoptosis and impaired retinal mitochondria. A retinal pigment epithelial cell line (ARPE-19) was used to verify the phototoxicity of blue light. Flow cytometry, immunofluorescence and MitoSox Red probe experiments confirmed that more total and mitochondria-specific ROS were generated in the blue light group than in the control group. Mito-Tracker Green probe showed fragmented mitochondrial morphology. The western blotting results indicated a significant increase in DRP1, OMA1, and BAX and a decrease in OPA1 and Bcl-2. In conclusion, long-term exposure to blue light damaged the retinas of mice, especially the ONL and RPE cells. There was destruction and dysfunction of mitochondria in RPE cells in vivo and in vitro. Mitochondrial dynamics were disrupted with characteristics of fusion-related obstruction after blue-light irradiation.


Asunto(s)
Degeneración Retiniana , Ratones , Animales , Degeneración Retiniana/etiología , Especies Reactivas de Oxígeno/metabolismo , Dinámicas Mitocondriales , Ratones Endogámicos C57BL , Retina/metabolismo , Estrés Oxidativo/efectos de la radiación , Luz , Epitelio Pigmentado de la Retina
19.
Autophagy ; 19(1): 92-111, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35473441

RESUMEN

In dry age-related macular degeneration (AMD), LCN2 (lipocalin 2) is upregulated. Whereas LCN2 has been implicated in AMD pathogenesis, the mechanism remains unknown. Here, we report that in retinal pigmented epithelial (RPE) cells, LCN2 regulates macroautophagy/autophagy, in addition to maintaining iron homeostasis. LCN2 binds to ATG4B to form an LCN2-ATG4B-LC3-II complex, thereby regulating ATG4B activity and LC3-II lipidation. Thus, increased LCN2 reduced autophagy flux. Moreover, RPE cells from cryba1 KO, as well as sting1 KO and Sting1Gt mutant mice (models with abnormal iron chelation), showed decreased autophagy flux and increased LCN2, indicative of CGAS- and STING1-mediated inflammasome activation. Live cell imaging of RPE cells with elevated LCN2 also showed a correlation between inflammasome activation and increased fluorescence intensity of the Liperfluo dye, indicative of oxidative stress-induced ferroptosis. Interestingly, both in human AMD patients and in mouse models with a dry AMD-like phenotype (cryba1 cKO and KO), the LCN2 homodimer variant is increased significantly compared to the monomer. Sub-retinal injection of the LCN2 homodimer secreted by RPE cells into NOD-SCID mice leads to retinal degeneration. In addition, we generated an LCN2 monoclonal antibody that neutralizes both the monomer and homodimer variants and rescued autophagy and ferroptosis activities in cryba1 cKO mice. Furthermore, the antibody rescued retinal function in cryba1 cKO mice as assessed by electroretinography. Here, we identify a molecular pathway whereby increased LCN2 elicits pathophysiology in the RPE, cells known to drive dry AMD pathology, thus providing a possible therapeutic strategy for a disease with no current treatment options.Abbreviations: ACTB: actin, beta; Ad-GFP: adenovirus-green fluorescent protein; Ad-LCN2: adenovirus-lipocalin 2; Ad-LCN2-GFP: adenovirus-LCN2-green fluorescent protein; LCN2AKT2: AKT serine/threonine kinase 2; AMBRA1: autophagy and beclin 1 regulator 1; AMD: age-related macular degeneration; ARPE19: adult retinal pigment epithelial cell line-19; Asp278: aspartate 278; ATG4B: autophagy related 4B cysteine peptidase; ATG4C: autophagy related 4C cysteine peptidase; ATG7: autophagy related 7; ATG9B: autophagy related 9B; BLOC-1: biogenesis of lysosomal organelles complex 1; BLOC1S1: biogenesis of lysosomal organelles complex 1 subunit 1; C57BL/6J: C57 black 6J; CGAS: cyclic GMP-AMP synthase; ChQ: chloroquine; cKO: conditional knockout; Cys74: cysteine 74; Dab2: DAB adaptor protein 2; Def: deferoxamine; DHE: dihydroethidium; DMSO: dimethyl sulfoxide; ERG: electroretinography; FAC: ferric ammonium citrate; Fe2+: ferrous; FTH1: ferritin heavy chain 1; GPX: glutathione peroxidase; GST: glutathione S-transferase; H2O2: hydrogen peroxide; His280: histidine 280; IFNL/IFNλ: interferon lambda; IL1B/IL-1ß: interleukin 1 beta; IS: Inner segment; ITGB1/integrin ß1: integrin subunit beta 1; KO: knockout; LC3-GST: microtubule associated protein 1 light chain 3-GST; C-terminal fusion; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; LCN2: lipocalin 2; mAb: monoclonal antibody; MDA: malondialdehyde; MMP9: matrix metallopeptidase 9; NLRP3: NLR family pyrin domain containing 3; NOD-SCID: nonobese diabetic-severe combined immunodeficiency; OS: outer segment; PBS: phosphate-buffered saline; PMEL/PMEL17: premelanosome protein; RFP: red fluorescent protein; rLCN2: recombinant LCN2; ROS: reactive oxygen species; RPE SM: retinal pigmented epithelium spent medium; RPE: retinal pigment epithelium; RSL3: RAS-selective lethal; scRNAseq: single-cell ribonucleic acid sequencing; SD-OCT: spectral domain optical coherence tomography; shRNA: small hairpin ribonucleic acid; SM: spent medium; SOD1: superoxide dismutase 1; SQSTM1/p62: sequestosome 1; STAT1: signal transducer and activator of transcription 1; STING1: stimulator of interferon response cGAMP interactor 1; TYR: tyrosinase; VCL: vinculin; WT: wild type.


Asunto(s)
Ferroptosis , Degeneración Macular , Animales , Humanos , Ratones , Anticuerpos Monoclonales , Autofagia/fisiología , Inflamasomas/metabolismo , Lipocalina 2/genética , Degeneración Macular/genética , Degeneración Macular/metabolismo , Degeneración Macular/patología , Ratones Endogámicos NOD , Ratones SCID , Nucleotidiltransferasas/metabolismo
20.
Ir J Med Sci ; 192(4): 1979-1986, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36094732

RESUMEN

BACKGROUND: To investigate clinical outcomes in patients with dry age-related macular degeneration (AMD) after intracapsular implantation of a novel EyeMax Mono macular lens. METHODS: In this study, 22 phakic eyes of 19 moderate to advanced dry AMD patients with macular disciform scar and/or macular atrophy who were followed up for ≥ 3 months after surgery were studied. A thorough pre-operative ophthalmological examination was performed, including measurement of corrected distance visual acuity in logMAR and ETDR. Following phacoemulsification, the EyeMax Mono lens was implanted intracapsularly via a 2.2-mm clear corneal incision to improve retinal image quality in all areas of the macula ≤ 10° from the central fovea. Main outcome measures included optimisation of corrected distance visual acuity and surgical safety. RESULTS: Male-to-female ratio was 13:6. Mean age at surgery was 68.37 ± 10.23 years. The mean duration of post-operative follow-up was 7.91 ± 3.42 months. The mean post-operative refractive spherical equivalent improved to + 2.31 ± 1.56 D with significant visual improvement as early as 3 months post-operatively. Post-operative corrected distance visual acuity improved significantly from 1.05 ± 0.45 to 0.72 ± 0.43 logMAR (P < 0.001), equivalent to mean ETDRS of 49.55 ± 20.05 (P < 0.001). There were no major surgical complications, either intra- or post-operatively, except in two patients who experienced intra-operative haptic rupture. CONCLUSIONS: Extended macular vision lenses appear to have a comparable safety profile as standard IOLs in the short to medium term. It could be the preferred lens for improving and preserving visual acuity in moderate to advanced dry AMD patients.


Asunto(s)
Extracción de Catarata , Lentes Intraoculares , Degeneración Macular , Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Implantación de Lentes Intraoculares/métodos , Agudeza Visual , Degeneración Macular/cirugía
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