Despite possessing limited protein-coding potential, long non-coding RNAs (lncRNAs) have been implicated in a myriad of pathologic conditions. Most well documented in cancer, one prominent intergenic ...lncRNA known as MALAT1 is notorious for its role in impacting epigenetic mechanisms. In this study, we established a novel epigenetic paradigm for MALAT in diabetic retinopathy (DR) by employing siRNA-mediated MALAT1 knockdown in human retinal endothelial cells (HRECs), a Malat1 knockout animal model, vitreous humor from diabetic patients, pharmacological inhibitors for histone and DNA methylation, RNA immunoprecipitation, western blotting, and a unique DNA methylation array to determine glucose-related alterations in MALAT1. Our findings indicated that MALAT1 is capable of impacting the expressions of inflammatory transcripts through its association with components of the PRC2 complex in diabetes. Furthermore, the vitreous humors from diabetic patients revealed increased expressions of MALAT1, TNF-α, and IL-6. Intriguingly, our DNA methylation array demonstrated that transient high glucose exposure in HRECs does not contribute to significant methylation alterations at CpG sites across the MALAT1 gene. However, global inhibition of DNA methyltransferases induced significant increases in MALAT1 and associated inflammatory transcripts in HRECs. Our findings collectively demonstrate the importance of MALAT1 in inflammation and epigenetic regulation in DR.
Suboptimal diabetic eye disease screening is a major cause of preventable vision loss. Screening barriers include mydriasis and the need for dedicated screening appointments. The Clearsight trial ...assessed whether nonmydriatic ultra-widefield (NM UWF) screening on the day of a diabetes clinic visit improved detection of clinically important eye disease versus usual screening.
This single-center, randomized, parallel-group controlled trial was conducted at St. Joseph's Health Care, London, Ontario, Canada. Adults with diabetes due for screening were randomized to same-day, on-site screening (NM UWF imaging) on the day of a scheduled diabetes clinic visit or usual screening (encouraged to arrange optometrist screening). The primary outcome was detection of actionable eye disease (AED), defined as the need for an ophthalmology referral or increased ocular surveillance. The primary analysis (modified intention-to-screen) compared the proportions of AED between groups within 1 year of enrollment.
Of 740 participants randomized between 7 March 2016 and 17 April 2019, 335 on-site screening and 323 usual screening participants met criteria for the primary analysis. More AED was detected in the on-site screening group than in the usual screening group (50 of 335 14.9% vs. 22 of 323 6.8%; adjusted odds ratio 2.51; 95% CI 1.49-4.36). The number needed to screen by on-site screening in order to detect 1 additional patient with AED was 13 (95% CI 8-29).
Same-day, on-site screening by NM UWF imaging increased the detection of clinically important diabetic eye disease versus usual screening. Integration of NM UWF imaging into routine diabetes clinic visits improved screening adherence and has the potential to prevent vision loss.
To assess the efficacy and safety of intravitreal inserts releasing 0.2 μg/day (low dose) or 0.5 μg/day (high dose) fluocinolone acetonide (FA) in patients with diabetic macular edema (DME).
Two ...parallel, prospective, randomized, sham injection-controlled, double-masked, multicenter clinical trials.
Subjects with persistent DME despite at least 1 macular laser treatment were randomized 1:2:2 to sham injection (n = 185), low-dose insert (n = 375), or high-dose insert (n = 393).
Subjects received study drug or sham injection at baseline and after 6 weeks were eligible for rescue laser. Based on retreatment criteria, additional study drug or sham injections could be given after 1 year.
The primary outcome was the percentage of patients with improvement from baseline best-corrected visual acuity (BCVA) in Early Treatment Diabetic Retinopathy Trial (ETDRS) letter score of 15 or more at month 24. Secondary outcomes included other parameters of visual function and foveal thickness (FTH).
The percentage of patients with improvement from baseline ETDRS letter score of 15 or more at month 24 was 28.7 and 28.6 in the low- and high-dose insert groups, respectively, compared with 16.2 in the sham group (P = 0.002 for each). Benefit occurred for both doses compared with sham at 3 weeks and all subsequent time points. The mean improvement in BCVA letter score between baseline and month 24 was 4.4 and 5.4 in the low- and high-dose groups, respectively, compared with 1.7 in the sham group (P = 0.02 and P = 0.016). At all time points compared with sham, there was significantly more improvement in FTH. Subjects requiring cataract surgery were more frequent in the insert groups, and their visual benefit was similar to that of subjects who were pseudophakic at baseline. Glaucoma requiring incisional surgery occurred in 3.7%, 7.6%, and 0.5% of the low-dose, high-dose, and sham groups, respectively.
Both low- and high-dose FA inserts significantly improved BCVA in patients with DME over 2 years, and the risk-to-benefit ratio was superior for the low-dose insert. This is the first pharmacologic treatment that can be administered by an outpatient injection to provide substantial benefit in patients with DME for at least 2 years.
With increasing incidence of diabetes worldwide, there is an ever-expanding number of patients with chronic diabetic complications such as diabetic retinopathy (DR), one of the leading causes of ...blindness in the working age population. Early screening for the onset and severity of DR is essential for timely intervention. With recent advancements in genomic technologies, epigenetic alterations in DR are beginning to unravel. Long non-coding RNAs (lncRNAs), which are key epigenetic mediators, have demonstrated implications in several (DR) related processes. Based on the previous research, we have developed a serum-based, multi-panel PCR test using 9 lncRNAs (
,
,
,
,
,
,
,
, and
) to identify and validate whether this panel could be used as a diagnostic and prognostic tool for DR. We initially used a cell culture model (human retinal endothelial cells) and confirmed that 25 mM glucose induces upregulations of
,
,
,
, and
, and downregulation of
compared to 5 mM glucose controls. Then as an initial proof-of-concept, we tested vitreous humor and serum samples from a small cohort of non-diabetic (N=10) and diabetic patients with proliferative retinopathy (PDR, N=11) and measured the levels of the 9 lncRNAs. Differential expressions of lncRNAs were found in the vitreous and serum of patients and showed significant correlations. We expanded our approach and assessed the same lncRNAs using samples from a larger cohort of diabetic (n= 59; M/F:44/15) and non-diabetic patients (n= 11; M/F:4/7). Significant increased lncRNA expressions of
,
,
,
,
,
and
were observed in the serum of diabetic patients (with varying stages of DR) compared to non-diabetics. No significant correlations were demonstrated between lncRNA expressions and creatinine or glycated hemoglobin (HbA1C) levels. Using ROC and further analyses, we identified distinct lncRNA phenotype combinations, which may be used to identify patients with DR. Data from this study indicate that a panel of serum lncRNAs may be used for a potential screening test for DR. Further large-scale studies are needed to validate this notion.
To assess the efficacy of intravitreal aflibercept in treating visual loss and structural changes in patients with pigment epithelial detachments (PED) secondary to neovascular age-related macular ...degeneration (nAMD).
Prospective, exploratory, open-label study (ClinicalTrials.gov Identifier: NCT02142296). Participants with PED secondary to nAMD were enrolled and received intravitreal aflibercept injection on a monthly basis for 3 months, followed by injections on a bimonthly basis for another 9 months. Best-corrected visual acuity (BCVA), ophthalmic examinations, optical coherence tomography (OCT) imaging, and fluorescein angiography were performed based on a predetermined schedule.
Thirty-six participants (37 eyes) were enrolled. At the end of study, 74.3% eyes demonstrated PED height reduction of 25% or more and 34.3% demonstrated complete resolution. The average reduction in retinal thickness was 128.4 μm. Participant eyes who had at least a 25% reduction in PED height at month 4 were labelled as “responders” (73.0%, n = 27), and those who had less than 25% reduction in PED height were labelled as “partial-responders” (27.0%, n = 10). Responders demonstrated more significant reduction in PED height than partial-responders (p <0.0001). The average gain in BCVA was 10.1 Early Treatment Diabetic Retinopathy Study (ETDRS) letters. Responders demonstrated more gain in BCVA than partial-responders (p = 0.0018). Among the responders, 57.7% demonstrated disease recurrences with increase in PED height during bimonthly dosing.
Intravitreal aflibercept injection for patients with PEDs secondary to nAMD has high response rate with few adverse events. Responders demonstrated BCVA gains, as well as structural improvements. However, high recurrence rate was found on bimonthly maintenance dosing.
Évaluer l'efficacité de l'administration intravitréenne d'aflibercept dans le traitement de la perte de vision et des modifications structurales imputables aux décollements de l’épithélium pigmentaire (DÉP) secondaires à la DMLA (dégénérescence maculaire liée à l’âge) néovasculaire.
Il s'agit d'une étude prospective et exploratoire sans insu (numéro d'identification sur le site clinicaltrials.gov: NCT02142296). Les participants qui présentaient des DÉP secondaires à la DMLA néovasculaire ont été admis à l’étude et ont reçu une injection intravitréenne d'aflibercept une fois par mois pendant 3 mois, suivie d'une injection tous les 2 mois pendant 9 mois supplémentaires. La meilleure acuité visuelle corrigée (MAVC), les examens ophtalmologiques, l'imagerie OCT (optical coherence tomography) et l'angiographie fluorescéinique ont été réalisés selon un calendrier préétabli.
Ont été admis 36 participants (37 yeux). À la fin de l’étude, 74,3 % des yeux avaient bénéficié d'une réduction de l’épaisseur des DÉP d'au moins 25 %, tandis que 34,3 % des yeux ont profité d'une résolution complète du problème. La réduction moyenne de l’épaisseur rétinienne se chiffrait à 128,4 μm. On a qualifié de « répondants » les sujets dont les yeux ont manifesté une réduction d'au moins 25 % de l’épaisseur des DÉP au mois 4 (73,0 %; n = 27); la « réponse partielle » qualifiait les sujets qui ont bénéficié d'une réduction de moins de 25 % de l’épaisseur des DÉP (27,0 %; n = 10). Les répondants ont bénéficié d'une réduction plus significative de l’épaisseur des DÉP que les sujets qui n'ont manifesté qu'une réponse partielle (p < 0,0001). L'amélioration moyenne de la MAVC se chiffrait à 10,1 lettres sur l’échelle ETDRS (Early Treatment Diabetic Retinopathy Study). L'augmentation de la MAVC des répondants était plus importante que celle des sujets qui n'ont eu qu'une réponse partielle (p = 0,0018). Parmi les répondants, 57,7 % ont subi des récurrences de leur maladie se traduisant par un épaississement des DÉP pendant le traitement d'entretien administré tous les 2 mois.
L'injection intravitréenne d'aflibercept dans le traitement des DÉP secondaires à la DMLA néovasculaire procure un taux de réponse élevé et entraîne peu d'effets indésirables. Les répondants ont bénéficié d'une amélioration de leur MAVC et de la structure épithéliale. Cela dit, on a enregistré un taux de récurrence élevé pendant le traitement d'entretien administré tous les 2 mois.
Introduction
VKH disease is a chronic, bilateral, granulomatous panuveitis with potential involvement of neurological, auditory and integumentary systems. On the other hand, APMPPE is believed to be ...an immune-driven chorioretinal vascular disease characterized by multifocal, flat, grey-white placoid lesions at the level of the RPE. We describe a case with overlapping figures of both conditions.
Case description
A 19-year-old female presented with unilateral blurry vision and was found to have clinical and IVFA findings consistent with APMPPE. Her OCT study demonstrated typical VKH findings with large areas of serous neurosensory retinal detachment and intra-retinal cystoid spaces with enclosed membranous structures. She was closely followed but was not treated with high dose corticosteroid. Spontaneous and complete resolution of her symptoms and clinical, IVFA and OCT findings were achieved by day 25.
Discussion
This is the first reported case of spontaneously resolving, unilateral VKH disease in the absence of high dose corticosteroid treatment with overlapping features of APMPPE.
Conclusions
The imaging and clinical findings of both VKH disease and APMPPE raise the notion that VKH disease and APMPPE could be an overlapping spectrum of inflammatory processes, rather than distinct disease entities.
Purpose. To characterize the economic and quality of life burden of diabetic macular edema (DME) in Canadian patients. Patients and Methods. 145 patients with DME were followed for 6 months with ...monthly telephone interviews and medical chart reviews at months 0, 3, and 6. Visual acuity in the worst-seeing eye was assessed at months 0 and 6. DME-related healthcare costs were determined over 6 months, and vision-related (National Eye Institute Visual Functioning Questionnaire) and generic (EQ-5D) quality of life was assessed at months 0, 3, and 6. Results. Mean age of patients was 63.7 years: 52% were male and 72% had bilateral DME. At baseline, visual acuity was categorized as normal/mild loss for 63.4% of patients, moderate loss for 10.4%, and severe loss/nearly blind for 26.2%. Mean 6-month DME-related costs/patient were as follows: all patients ( n = 135 ), $2,092; normal/mild loss ( n = 88 ), $1,776; moderate loss ( n = 13 ), $1,845; and severe loss/nearly blind ( n = 34 ), $3,007. Composite scores for vision-related quality of life declined with increasing visual acuity loss; generic quality of life scores were highest for moderate loss and lowest for severe loss/nearly blind. Conclusions. DME-related costs in the Canadian healthcare system are substantial. Costs increased and vision-related quality of life declined with increasing visual acuity severity.
Aims/hypothesis
The pathophysiology of diabetic retinopathy is linked to hyperglycaemia and its effect on retinal microvascular tissues. The resulting endothelial injury changes the endothelial cell ...phenotype to acquire mesenchymal properties (i.e. endothelial–mesenchymal transition EndMT). Such changes can be regulated by epigenetic mechanisms, including long non-coding RNAs (lncRNAs). lncRNA H19 may influence EndMT through TGF-β. We investigated the role of H19 in regulating EndMT during diabetic retinopathy.
Methods
H19 was overexpressed or silenced in human retinal endothelial cells exposed to various glucose levels. The cells were examined for H19, endothelial and mesenchymal markers. We then expanded the study to retinal tissues in a mouse model of diabetic retinopathy and also examined vitreous humour samples from individuals with proliferative diabetic retinopathy.
Results
Expression of H19 was downregulated in high glucose conditions (25 mmol/l). H19 overexpression prevented glucose-induced EndMT. Such changes appear to involve TGF-β through a Smad-independent mechanism. Diabetes caused downregulation of retinal H19. Using
H19
knockout mice, we demonstrated similar EndMT in the retina. Examination of vitreous humour from individuals with proliferative diabetic retinopathy also reinforced the downregulation of H19 in diabetes.
Conclusions/interpretation
We therefore concluded that H19 regulates EndMT in diabetic retinopathy through specific mechanisms.
Data availability
The results from our previous microarray can be found online using the GEO accession number GSE122189.
Oncofetal Fibronectin in Diabetic Retinopathy Khan, Zia A; Cukiernik, Mark; Gonder, John R ...
Investigative ophthalmology & visual science,
01/2004, Letnik:
45, Številka:
1
Journal Article
Recenzirano
Imbalance between extracellular matrix protein synthesis and degradation is a key feature of diabetic retinopathy. Fibronectin, a predominant constituent of the extracellular matrix, has been shown ...to undergo alternative splicing to produce embryonic isoforms in various pathologic conditions, such as fibrotic diseases and tumorigenesis. Two such isoforms, oncofetal fibronectin variants that are characterized by the inclusion of the oncofetal domains A and B, were the focus of the present study.
The expression of oncofetal fibronectin variants was determined in human vitreous samples obtained from patients undergoing vitrectomy for proliferative diabetic retinopathy and nondiabetes-associated ocular conditions such as macular hole. In addition, an animal model of chronic diabetes and cultured endothelial cells was used to elucidate the mechanistic basis for this aberrant expression of oncofetal fibronectin.
Expression of fibronectin containing the oncofetal domain B was upregulated in the vitreous of patients with diabetic retinopathy.
Use of a well-established animal model of chronic diabetic complications and cultured endothelial cells showed that diabetes-induced upregulation of oncofetal fibronectin is, in part, dependent on hyperglycemia-induced transforming growth factor-beta1 and endothelin-1. Furthermore, the data suggest that oncofetal fibronectin is involved in endothelial cell proliferation.
IntroductionSuboptimal screening for diabetic eye disease is a major cause of preventable vision loss. Screening barriers include mydriasis and the extra time patients need to attend dedicated eye ...screening appointments. In the Clearsight trial, we are testing whether screening by non-mydriatic ultra-wide field (NM UWF) imaging on the day patients attend their diabetes outpatient clinic visit improves detection of clinically important eye disease compared with usual screening.Methods and analysisPatients with diabetes due for a screening eye exam by the 2013 Canadian Diabetes Association (CDA) practice guidelines are being randomised to on-site screening by NM UWF imaging on the day of their clinic visit or to usual screening where, per CDA guidelines, they are encouraged to arrange an exam by an optometrist. The primary outcome is actionable eye disease (AED) based on a need for referral to ophthalmology and/or increased ocular surveillance. The primary analysis will use an intention-to-screen approach that compares the proportions of detected AED between on-site and usual screening groups under a superiority hypothesis in favour of on-site screening. With 740 randomised participants, the study will have 80% power to detect ≥5% absolute increase in the AED rate among on-site screening versus usual screening participants. This difference translates into a number-needed-to-screen by on-site screening of 20 to detect 1 additional person with AED.Ethics and disseminationThe protocol was approved by the institutional review board of Western University. The findings of the trial will be disseminated directly to participants and through peer-reviewed publications and conference presentations.Trial registration numberClinicalTrials.Gov NCT02579837 (registered 16 October 2015).Protocol issue date18 November 2015.
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