RNA‐seq analysis of ageing human retinal pigment epithelium: Unexpected up‐regulation of visual cycle gene transcription

Butler, Joe; Supharattanasitthi, Wasu; Yang, Yit; Paraoan, Luminita

doi:10.1111/jcmm.16569

Cited by 21 publications

(20 citation statements)

References 67 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“… 61 Our data are also important for interpreting studies of visual cycle and bisretinoid biochemistry using whole eyecup preparations of human eyes. 62 , 63 Our data do not rule out undiscovered bisretinoids as major signal sources for clinical fundus autofluorescence imaging. In fact, our data should further propel the search for such compounds.…”

Section: Discussioncontrasting

confidence: 65%

Retinal Pigment Epithelium in Human Donor Eyes Contains Higher Levels of Bisretinoids Including A2E in Periphery than Macula

Kotnala

Senthilkumari²,

Gong

et al. 2022

Invest. Ophthalmol. Vis. Sci.

View full text Add to dashboard Cite

Purpose With age, human retinal pigment epithelium (RPE) accumulates bisretinoid fluorophores that may impact cellular function and contribute to age-related macular degeneration (AMD). Bisretinoids are comprised of a central pyridinium, dihydropyridinium, or cyclohexadiene ring. The pyridinium bisretinoid A2E has been extensively studied, and its quantity in the macula has been questioned. Age-changes and distributions of other bisretinoids are not well characterized. We measured levels of three bisretinoids and oxidized A2E in macula and periphery in human donor eyes of different ages. Methods Eyes ( N = 139 donors, 61 women and 78 men, aged 40–80 years) were dissected into 8 mm diameter macular and temporal periphery punches. Using liquid chromatography – electrospray ionization – mass spectrometry (LC-ESI-MS) and an authentic synthesized standard, we quantified A2E (ng). Using LC-ESI-MS and a 50-eye-extract of A2E, we semiquantified A2E and 3 other compounds (eye extract equivalent units [EEEUs): A2-glycerophosphoethanolamine (A2GPE), dihydropyridine phosphatidyl ethanolamine (A2DHPE), and monofuranA2E (MFA2E). Results A2E quantities in ng and EEEUs were highly correlated ( r = 0.97, P < 0.001). From 262 eyes, 5 to 9-fold higher levels were observed in the peripheral retina than in the macula for all assayed compounds. A2E, A2DHPE, and MFA2E increased with age, whereas A2GPE remained unaffected. No significant right-left or male-female differences were detected. Conclusions Significantly higher levels were observed in the periphery than in the macula for all assayed compounds signifying biologic differences between these regions. Levels of oxidized A2E parallel native A2E and not the distribution of retinal illuminance. Data will assist with the interpretion of clinical trial outcomes of agents targeting bisretinoid-related pathways.

show abstract

Section: Discussioncontrasting

confidence: 65%

Retinal Pigment Epithelium in Human Donor Eyes Contains Higher Levels of Bisretinoids Including A2E in Periphery than Macula

Kotnala

Senthilkumari²,

Gong

et al. 2022

Invest. Ophthalmol. Vis. Sci.

View full text Add to dashboard Cite

show abstract

“…Notably, PRPF31 was also associated with the RLBP1 immunostained aggregates in RP11‐RPE cells. Upregulation of visual cycle genes in RPE cells has been associated with accumulation of retinoid by‐products in the aged RPE cells 35 . These results suggest that RP11‐RPE cells might develop similar features to aged RPE.…”

Section: Resultsmentioning

confidence: 75%

“…GOBP enrichment analysis identified 31 DE proteins involved in visual perception as one of the most enriched compartments (Figure 4F, Table S3) including RLBP1, RDH11 and RDH5, which are important proteins involved in the generation of the visual pigment and hence the maintenance of vision. Dysregulated expression of proteins involved in the visual cycle suggests changes in retinoid by‐products in retinal organoids, which have been associated with retinal degeneration 35 and deserve further investigations.…”

Section: Resultsmentioning

confidence: 99%

“…The mislocalisation of FUS from the nucleus to the cytoplasm has been reported previously by other studies and it has been associated with amyotrophic lateral sclerosis (ALS). 30 Nineteen proteins involved in visual perception and 18 proteins in the retinoid metabolic pathway were DE, and of these one the most upregulated protein was RLBP1, a protein up-regulated with age in RPE cells 31 and associated with a range of retinal dystrophies including nonsyndromic autosomal recessive RP 32 and Newfoundland rod-cone dystrophy 33 (Figure 3A, Table S2). RLBP1 is a soluble retinoid carrier, which plays an important role in the regeneration of 11-cis-retinol during the visual cycle.…”

Section: Quantitative Proteomics Reveals Major Pathways Affected In P...mentioning

confidence: 99%

See 1 more Smart Citation

Activation of autophagy reverses progressive and deleterious protein aggregation in PRPF31 patient‐induced pluripotent stem cell‐derived retinal pigment epithelium cells

Γεωργίου

Yang

Atkinson

et al. 2022

Clinical & Translational Med

View full text Add to dashboard Cite

Introduction Mutations in pre‐mRNA processing factor 31 (PRPF31), a core protein of the spliceosomal tri‐snRNP complex, cause autosomal‐dominant retinitis pigmentosa (adRP). It has remained an enigma why mutations in ubiquitously expressed tri‐snRNP proteins result in retina‐specific disorders, and so far, the underlying mechanism of splicing factors‐related RP is poorly understood. Methods We used the induced pluripotent stem cell (iPSC) technology to generate retinal organoids and RPE models from four patients with severe and very severe PRPF31‐adRP, unaffected individuals and a CRISPR/Cas9 isogenic control. Results To fully assess the impacts of PRPF31 mutations, quantitative proteomics analyses of retinal organoids and RPE cells were carried out showing RNA splicing, autophagy and lysosome, unfolded protein response (UPR) and visual cycle‐related pathways to be significantly affected. Strikingly, the patient‐derived RPE and retinal cells were characterised by the presence of large amounts of cytoplasmic aggregates containing the mutant PRPF31 and misfolded, ubiquitin‐conjugated proteins including key visual cycle and other RP‐linked tri‐snRNP proteins, which accumulated progressively with time. The mutant PRPF31 variant was not incorporated into splicing complexes, but reduction of PRPF31 wild‐type levels led to tri‐snRNP assembly defects in Cajal bodies of PRPF31 patient retinal cells, altered morphology of nuclear speckles and reduced formation of active spliceosomes giving rise to global splicing dysregulation. Moreover, the impaired waste disposal mechanisms further exacerbated aggregate formation, and targeting these by activating the autophagy pathway using Rapamycin reduced cytoplasmic aggregates, leading to improved cell survival. Conclusions Our data demonstrate that it is the progressive aggregate accumulation that overburdens the waste disposal machinery rather than direct PRPF31‐initiated mis‐splicing, and thus relieving the RPE cells from insoluble cytoplasmic aggregates presents a novel therapeutic strategy that can be combined with gene therapy studies to fully restore RPE and retinal cell function in PRPF31‐adRP patients.

show abstract

“…The expression of visual cycle enzymes including LRAT, BCO1, RDH10, RDH11 and RPE65 increases with age. There is also evidence that Lrat expression in the RPE is driven by retinoid by-products of the visual cycle (A2E and all- trans -retinal) which activate RAR most likely via conversion to RA [ 171 ]. The activity of LRAT in the eye is not only required for storing vitamin A but also to form the precursor for the enzyme RPE65, the isomerohydrolase that regenerates 11- cis -retinaldehyde.…”

Section: Vitamin a Storagementioning

confidence: 99%

Mechanisms of Feedback Regulation of Vitamin A Metabolism

2022

View full text Add to dashboard Cite

Vitamin A is an essential nutrient required throughout life. Through its various metabolites, vitamin A sustains fetal development, immunity, vision, and the maintenance, regulation, and repair of adult tissues. Abnormal tissue levels of the vitamin A metabolite, retinoic acid, can result in detrimental effects which can include congenital defects, immune deficiencies, proliferative defects, and toxicity. For this reason, intricate feedback mechanisms have evolved to allow tissues to generate appropriate levels of active retinoid metabolites despite variations in the level and format, or in the absorption and conversion efficiency of dietary vitamin A precursors. Here, we review basic mechanisms that govern vitamin A signaling and metabolism, and we focus on retinoic acid-controlled feedback mechanisms that contribute to vitamin A homeostasis. Several approaches to investigate mechanistic details of the vitamin A homeostatic regulation using genomic, gene editing, and chromatin capture technologies are also discussed.

show abstract

RNA‐seq analysis of ageing human retinal pigment epithelium: Unexpected up‐regulation of visual cycle gene transcription

Cited by 21 publications

References 67 publications

Retinal Pigment Epithelium in Human Donor Eyes Contains Higher Levels of Bisretinoids Including A2E in Periphery than Macula

Retinal Pigment Epithelium in Human Donor Eyes Contains Higher Levels of Bisretinoids Including A2E in Periphery than Macula

Activation of autophagy reverses progressive and deleterious protein aggregation in PRPF31 patient‐induced pluripotent stem cell‐derived retinal pigment epithelium cells

Mechanisms of Feedback Regulation of Vitamin A Metabolism

Contact Info

Product

Resources

About