Changing vision: a review of pharmacogenetic studies for treatment response in age-related macular degeneration patients

The impact of NF-κB on inflammatory and angiogenic processes in age-related macular degeneration

Age-related macular degeneration (AMD) is a prominent cause of vision loss, characterized by two different types, dry (atrophic) and wet (neovascular). Dry AMD is distinguished by the progressive deterioration of retinal cells, which ultimately causes a decline in vision. In contrast, wet AMD is defined by the abnormal development of blood vessels underneath the retina, leading to a sudden and severe vision impairment. The course of AMD is primarily driven by chronic inflammation and pathological angiogenesis, in which the NF-κB signaling pathway plays a crucial role. The activation of NF-κB results in the generation of pro-inflammatory cytokines, chemokines, and angiogenic factors like VEGF, which contribute to inflammation and the formation of new blood vessels in AMD. This review analyzes the intricate relationship between NF-κB signaling, inflammation, and angiogenesis in AMD and assesses the possibility of using NF-κB as a target for therapy. The evaluation involves a comprehensive examination of preclinical and clinical evidence that substantiates the effectiveness of NF-κB inhibitors in treating AMD by diminishing inflammation and pathological angiogenesis.

Genetic Aspects of Age-Related Macular Degeneration and Their Therapeutic Potential

Age-related macular degeneration (AMD) is a complex and multifactorial disease, resulting from the interaction of environmental and genetic factors. The continuous discovery of associations between genetic polymorphisms and AMD gives reason for the pivotal role attributed to the genetic component to its development. In that light, genetic tests and polygenic scores have been created to predict the risk of development and response to therapy. Still, none of them have yet been validated. Furthermore, there is no evidence from a clinical trial that the determination of the individual genetic structure can improve treatment outcomes. In this comprehensive review, we summarize the polymorphisms of the main pathogenetic ways involved in AMD development to identify which of them constitutes a potential therapeutic target. As complement overactivation plays a major role, the modulation of targeted complement proteins seems to be a promising therapeutic approach. Herein, we summarize the complement-modulating molecules now undergoing clinical trials, enlightening those in an advanced phase of trial. Gene therapy is a potential innovative one-time treatment, and its relevance is quickly evolving in the field of retinal diseases. We describe the state of the art of gene therapies now undergoing clinical trials both in the field of complement-suppressors and that of anti-VEGF.

Artificial Intelligence Algorithms for Analysis of Geographic Atrophy: A Review and Evaluation

Purpose

The purpose of this study was to summarize and evaluate artificial intelligence (AI) algorithms used in geographic atrophy (GA) diagnostic processes (e.g. isolating lesions or disease progression).

Methods

The search strategy and selection of publications were both conducted in accordance with the Preferred of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed and Web of Science were used to extract literary data. The algorithms were summarized by objective, performance, and scope of coverage of GA diagnosis (e.g. lesion automation and GA progression).

Results

Twenty-seven studies were identified for this review. A total of 18 publications focused on lesion segmentation only, 2 were designed to detect and classify GA, 2 were designed to predict future overall GA progression, 3 focused on prediction of future spatial GA progression, and 2 focused on prediction of visual function in GA. GA-related algorithms reported sensitivities from 0.47 to 0.98, specificities from 0.73 to 0.99, accuracies from 0.42 to 0.995, and Dice coefficients from 0.66 to 0.89.

Conclusions

Current GA-AI publications have a predominant focus on lesion segmentation and a minor focus on classification and progression analysis. AI could be applied to other facets of GA diagnoses, such as understanding the role of hyperfluorescent areas in GA. Using AI for GA has several advantages, including improved diagnostic accuracy and faster processing speeds.

Translational Relevance

AI can be used to quantify GA lesions and therefore allows one to impute visual function and quality-of-life. However, there is a need for the development of reliable and objective models and software to predict the rate of GA progression and to quantify improvements due to interventions.

DICER1 in the Pathogenesis of Age-related Macular Degeneration (AMD) - Alu RNA Accumulation versus miRNA Dysregulation

DICER1 deficiency in the retinal pigment epithelium (RPE) was associated with the accumulation of Alu transcripts and implicated in geographic atrophy (GA), a form of age-related macular degeneration (AMD), an eye disease leading to blindness in millions of people. Although the exact mechanism of this association is not fully known, the activation of the NLRP3 inflammasome, maturation of caspase-1 and disruption in mitochondrial homeostasis in RPE cells were shown as critical for it. DICER1 deficiency results in dysregulation of miRNAs and changes in the expression of many genes important for RPE homeostasis, which may also contribute to AMD. DICER1 deficiency can change the functions of the miR-183/96/182 cluster that regulates photoreceptors and their synaptic transmission. Aging, the main AMD risk factor, is associated with decreased expression of DICER1 and changes in its diurnal pattern that are not synchronized with circadian regulation in the retina. The initial insult inducing DICER1 deficiency in AMD may be oxidative stress, another major risk factor of AMD, but further studies on the role of deficient DICER1 in AMD pathogenesis and its therapeutic potential are needed.

Pharmacological Advances in the Treatment of Age-related Macular Degeneration

Age-related macular degeneration is an acquired degenerative disease that is responsible for severe loss of vision in elderly people. There are two types: dry age-related macular degeneration and wet age-related macular degeneration. Its treatment has been improved and tries to be tailored in the future. The aim of this review is to summarize the pharmacological advances in the treatment of age-related macular degeneration. Regarding dry AMD, there is no effective treatment to reduce its progression. However, some molecules such as lampalizumab and eculizumab were under investigation, although they have shown low efficacy. Herein, in an attempt to prevent dry AMD progression, the most important studies suggested increasing the antioxidants intake and quitting the smoke habit. On the other hand, wet AMD has more developed treatment. Nowadays, the gold standard treatment is anti-VEGF injections. However, more effective molecules are currently under investigation. There are different molecules under research for dry AMD and wet AMD. This fact could help us treat our patients with more effective and lasting drugs but more clinical trials and safety studies are required in order to achieve an optimal treatment.

Thymoquinone protects human retinal pigment epithelial cells against hydrogen peroxide induced oxidative stress and apoptosis

Oxidative stress in retinal pigment epithelium (RPE) cells may contribute to the progression of age-related macular degeneration. Thymoquinone (TQ), an active component derived from Nigella sativa, possesses antioxidative effect. However, the role of TQ in RPE cells under oxidative stress condition remains unclear. The present study aimed to examine the protective effect of TQ against hydrogen peroxide (H₂ O₂ )-induced oxidative stress in human RPE cells. Our results showed that TQ improved the cell viability and apoptosis in H₂ O₂ -induced ARPE cells. We also found that the levels of reactive oxygen species and malondialdehyde induced by H₂ O₂ were reduced after the pretreatment of TQ. In addition, the inhibitory effect of H₂ O₂ on the glutathione (GSH) level and superoxide dismutase activity was markedly attenuated by TQ pretreatment. Moreover, TQ enhanced the activation of Nrf2/heme oxygenase 1 (HO-1) signaling pathway in H₂ O₂ -induced ARPE cells. Knockdown of Nrf2 abolished the protective effect of TQ on H₂ O₂ -induced oxidative damage. These results suggested that TQ protected ARPE cells from H₂ O₂ -induced oxidative stress and apoptosis via the Nrf2/HO-1 signaling pathway.