Metabolomics in Retinal Diseases: An Update

Abstract

Retinal diseases are a leading cause of visual loss and blindness, affecting a significant proportion of the population worldwide and having a detrimental impact on quality of life, with consequent economic burden. The retina is highly metabolically active, and a number of retinal diseases are associated with metabolic dysfunction. To better understand the pathogenesis underlying such retinopathies, new technology has been developed to elucidate the mechanism behind retinal diseases. Metabolomics is a relatively new “omics” technology, which has developed subsequent to genomics, transcriptomics, and proteomics. This new technology can provide qualitative and quantitative information about low-molecular-weight metabolites (M.W. < 1500 Da) in a given biological system, which shed light on the physiological or pathological state of a cell or tissue sample at a particular time point. In this article we provide an extensive review of the application of metabolomics to retinal diseases, with focus on age-related macular degeneration (AMD), diabetic retinopathy (DR), retinopathy of prematurity (ROP), glaucoma, and retinitis pigmentosa (RP).

Metabolomics of various samples advancing biomarker discovery and pathogenesis elucidation for diabetic retinopathy

“…The NMR spectrum is the basis of metabolomics because of its outstanding advantages, which are listed in Table 1 . These features guarantee the extensive application of NMR in metabolomics ( 25 , 26 ), especially 1 H NMR, as 1 H atoms exist in most organic metabolites ( 27 ). Despite the many benefits, such as the extreme NMR signal intensity caused by tremendous isotopic natural abundance, the NMR spectrum exhibits common resonance overlapping that obviously hinders quantifying and identifying metabolites.…”

“…However, there are still some disadvantages, like the decreased sensitivity of sample detection caused by the amounts of solvent during separation ( 23 , 32 ). In addition, advancements in NMR spectrometer hardware concentrate on sample probe heads and superconducting magnets, like miniaturizing probes and cryogenic cooling, which have enlarged the utility of NMR ( 27 ).…”

“…For metabolomic analysis, tandem MS was used to profile the metabolites deregulated after hypoxic disposal, and the abnormal metabolites included 7α-hydroxycholesterol, 7-ketocholesterol, and others. Furthermore, there are several studies on retinal lipidomics and proteomics ( 27 , 68 , 69 ). However, as a result of the difficulty of retinal sample collection, the results of retinal omics are not easily used for diagnostic or screening purposes.…”

Acylcarnitines in Ophthalmology: Promising Emerging Biomarkers

“…Metabolomics focuses on the identification and quantification of key metabolites involved in metabolic perturbations related to certain pathophysiological states in a biological system, and it is a powerful tool for investigating the pathogenesis of a disease and the discovery of new biomarkers [3,4]. With the development of precision medicine, metabolomic analysis has been applied in ocular-derived matrices, and some interesting reviews have been recently published [5][6][7][8]. According to the literature, the metabolic profile of eye biospecimens under normal or several pathological conditions has been studied, and several metabolites have been identified to be involved in these.…”

Modulating the Kynurenine pathway or sequestering toxic 3-hydroxykynurenine protects the retina from light induced damage in Drosophila

“…Tissue health is regulated by a myriad of exogenous and endogenous factors, and deregulation of signaling and metabolic pathways have been linked to human diseases. There is increasing evidence that metabolic pathways play crucial roles in the progression of, or protection from, neurodegenerative diseases, including Parkinson’s and Alzheimer’s disease (Camandola & Mattson, 2017) or retinal diseases (Fiedorowicz, Choragiewicz et al, 2019, Li, Cai et al, 2021, Pan, Wubben et al, 2021, Wubben, Pawar et al, 2017). In particular, the Kynurenine pathway (KP) has more recently attracted much attention.…”