Serum microRNA Levels in Diabetes Mellitus

Liposomal Ozonated Oil Ensures a Further Reduction in the Microbial Load Before Intravitreal Injection: the "OPERA" Study

INTRODUCTION

This was a prospective study to investigate the antimicrobial efficacy of a novel ophthalmic solution comprising ozonated sunflower oil in liposomes plus hypromellose in conjunction with liposomal foam (BlefOX), in patients undergoing intravitreal injection, in comparison to povidone iodine 5%.

METHODS

The study employed a paired-eye design with n = 195 patients and a total of n = 390 eyes divided into two groups. Conjunctival swabs were collected from both eyes of each patient at baseline (T0-3 days before the injection). The study group underwent home therapy, which included instilling two drops of an isotonic ophthalmic solution containing 0.5% ozonated sunflower oil in liposomes plus hypromellose (Ozodrop) four times daily and applying liposomal foam twice daily to the eye undergoing intravitreal injections. In contrast, the control group (contralateral eyes) received treatment with povidone iodine 5%. This treatment regimen was maintained for 3 days. At T1 (10 min before injection), all patients instilled one drop of a topical solution of povidone iodine 5% into the conjunctival sac of both eyes. After 30 seconds had elapsed, a conjunctival swab was obtained for each eye in both study groups.

RESULTS

The results, derived from conjunctival swabs, exhibited a significant reduction in the microbial load of the study group on both chocolate agar and blood agar (p ≤ 0.007). The study demonstrated that the combination of povidone iodine 5% + Ozodrop + BlefOX provides a greater reduction in microbial load than povidone iodine 5% alone on both chocolate agar (141 [72.31%] vs. 98 [50.26%], p < 0.0001) and blood agar (130 [66.67%] vs. 97 [49.74%], p = 0.0007). The combination of povidone iodine 5% + Ozodrop + BlefOX resulted in the killing of approximately 41% to 49% of bacteria compared to povidone iodine 5% alone on the chocolate agar and blood agar, respectively.

CONCLUSIONS

Liposomal ozonated oil treatment, coupled with liposomal foam, in patients undergoing intravitreal injection led to a substantial reduction in conjunctival microbial load compared to eyes treated solely with povidone iodine 5%.

In-silico identification and functional characterization of common genes associated with type 2 diabetes and hypertension

Type 2 diabetes (T2D) and hypertension are global public health concerns and major metabolic disorders in humans. Experimental evidence indicates considerable hereditary influences on the etiology of T2D and hypertension, but the molecular basis of these diseases is still limited. Thus, the current study analyzed 185 (132 T2D and 53 hypertension) GWAS catalog datasets and identified 83 common genes linked to T2D and hypertension pathogenesis. These genes were further examined using various bioinformatics approaches to elucidate their molecular mechanisms underlying the pathophysiology of T2D and hypertension. Gene ontology (GO) analysis revealed the biological, cellular, and molecular functions of these genes, which were also linked to different T2D and hypertension pathways. Specifically, seven genes were found to be crucial for T2D, and nine were directly associated with hypertension. Protein-protein interaction (PPI) analysis identified 28 candidate genes and seven hub genes through 11 topological methods. Among 231 miRNAs, seven were significant in interacting with the hub genes, and nine transcription factors (TFs) out of 36 were linked to these hub genes. Additionally, two of the seven hub genes were downregulated by 43 FDA-approved drugs. These findings elucidate the molecular processes underlying T2D and hypertension, suggesting that targeting these genes could lead to future drug development and therapeutic strategies to treat T2D and hypertension.

Comparison of diabetic retinopathy screening between hospital-based multidisciplinary and general practice-based settings: insights from a regional study in Italy

PURPOSE

To compare diabetic retinopathy screening among patients with type 1 or type 2 diabetes under care in two distinct setups: hospital-based multidisciplinary and general practice-based.

MATERIALS AND METHODS

In this retrospective observational case series, we collected data from a total of 133 diabetic patients: subjects from the hospital-based multidisciplinary setting were referred by the diabetologist and screened by an ophthalmologist using the Optomed Aurora IQ fundus camera. These patients were compared with those who underwent DR screening arranged through a general practice-based setting.

RESULTS

The proportion of patients treated with insulin was higher in the hospital-based multidisciplinary group, both considering the totality patients and those affected by type 2 diabetes (71.6% vs. 32.2%; p < 0.001, and 58.8% vs. 31.0%; p = 0.004 respectively). Patients from the hospital-based multidisciplinary group had a longer mean diabetes duration (19.6 vs 14.9 years, p < 0.001), underwent DR screening more frequently in the previous three years (2.9 vs 1.4, p < 0.001), the mean time between two DR screenings was shorter (14.6 vs 77.9 weeks, p < 0.001), and DR was detected more frequently (32,4% vs 13.5%; p = 0.011).

CONCLUSION

We were able to demonstrate that patients screened in the multidisciplinary center, which had characteristics predisposing to a higher risk of DR, were more likely to be diagnosed with DR on time, with a higher mean number of DR screenings and a shorted interval between diabetic and ophthalmological assessments.

Long-Term Impact of Diabetic Retinopathy on Response to Anti-VEGF Treatment in Neovascular AMD

Purpose

To explore the long-term effect of diabetic retinopathy on response to anti-vascular endothelial growth factor (VEGF) treatment in age-related macular degeneration-associated type 1 macular neovascularization (MNV) using optical coherence tomography angiography (OCTA).

Methods

A total of 45 eyes with exudative neovascular age-related macular degeneration (nAMD) with type 1 MNV were included in the analysis. Among them, 24 eyes of 24 patients had no history of diabetes mellitus (DM) in their anamnesis and were assigned to the Not Diabetic group; 21 eyes of 21 patients had mild diabetic retinopathy and were included in the Diabetic group. We considered the following outcome measures: (1) best-corrected visual acuity changes; (2) central macular thickness; (3) MNV lesion area; and (4) MNV flow area. The OCTA acquisitions were performed at the following time points: (1) baseline visit, which corresponded to the day before the first injection; (2) post-loading phase (LP), which was scheduled at 1 month after the last LP injection; and (3) 12-month follow-up visit.

Results

All morphofunctional parameters showed a significant improvement after the LP and at the 12-month follow-up visit. Specifically, both the Diabetic group and the Not Diabetic group displayed a significant reduction of MNV lesion areas at both the post-LP assessment (P = 0.026 and P = 0.016, respectively) and the 12-month follow-up (P = 0.039 and P = 0.025, respectively). Similarly, the MNV flow area was significantly decreased in both the Diabetic group and the Not Diabetic group at the post-LP assessment (P < 0.001 and P = 0.012, respectively) and at the 12-month follow-up (P = 0.01 and P = 0.035, respectively) compared to baseline. A smaller reduction in the MNV lesion area was observed in the Diabetic group at both the post-LP evaluation (P = 0.015) and the 12-month follow-up (P = 0.032). No other significant differences were found between the groups for the other parameters (P > 0.05).

Conclusions

Our results indicated that the Diabetic group exhibited a smaller reduction in MNV lesion area after 12 months of anti-VEGF treatment. This highlights the importance of considering diabetic retinopathy as a potential modifier of treatment outcomes in nAMD management, with DM serving as a crucial risk factor during anti-angiogenic treatment.

Immediate effect of anti-VEGF injections on optic nerve head: Correlation between intraocular pressure and anatomical peripapillary changes

PURPOSE

This study was designed to investigate retinal nerve fiber layer (RNFL) and radial peripapillary capillaries (RPC) changes on optical coherence tomography (OCT) angiography and OCT thickness alterations associated with acutely increased intraocular pressure after intravitreal injections.

METHODS

This observational clinical study was conducted on 35 eyes (35 patients) with treatment-naïve age-related macular degeneration (AMD) and type 1 or type 2 MNV were enrolled. All patients underwent anti-vascular endothelial grow factor (VEGF) intravitreal injections with 0.05-mL aflibercept (2 mg) between January 2022 and October 2022. Peripapillary OCT angiography perfusion density, retinal nerve fiber layer thickness, and intraocular pressure (IOP) were measured before and immediately after intravitreal injections. In particular, the analysis was performed at the following visits: (T0) 5 to 15 min before the injection of aflibercept; (T1) 2 to 5 min after the injection of aflibercept. Paired t-test was used to compare pre-injection and post-injection values.

RESULTS

The mean baseline IOP (T0) value was 17.26 ± 2.4 mmHg and the immediate post-injection IOP (T1) mean value was 34.7 ± 11.50 mmHg (P < 0.01). The mean global RNFL thickness before and immediately after the injection was 100.9 ± 18.8 m and 98.6 ± 17.4 m (P = 0.001). Furthermore, the topographical RNFL analysis showed significant thickness reduction of the nasal and inferior sectors after the procedure when compared to T0 (P = 0.046 and P = 0.001). On the contrary, the mean RCP density changes at T1 did not reach statistically significant (P = 0.636). Furthermore, we found a significant negative correlation between the retinal nerve fiber layer global thickness and the IOP changes (Pearson's correlation = -0.126; P = 0.031). In particular, the nasal RNFL region showed a significant negative correlations with IOP values (Pearson's correlation = -0.198, P = 0,046).

CONCLUSIONS

We reported acute IOP changes that are associated with reduced RNFL thickness in a group of patients undergoing intravitreal injections of anti-VEGF drugs for neovascular age-related macular degeneration. Moreover, topographical sub-analysis revealed that the nasal RNFL region is most prone to IOP fluctuations. This finding may explain the sudden visual acuity change in patients immediately after injection and may sustain injuries to optic nerve head structures producing glaucomatous damage.

Outer retina and choroid as potential imaging markers for evaluation of neural impairment in early type 2 diabetic patients

PURPOSE

To quantify the presence of early structural alterations in the outer retinal layer and choroid among healthy subjects and diabetic patients with no or mild diabetic retinopathy, and to establish the correlation between the measured structural parameters and retinal sensitivity.

METHODS

In total, 31 eyes from subjects with type 2 diabetes and 29 eyes from healthy subjects were enrolled. Optical coherence tomography was used to measure outer retina layers and choroid, while microperimetry was used to characterize the changes of visual function in a 6-mm diameter area at macula. Quantitative analysis of structural and functional changes was performed between groups and the structure-function correlations were determined.

RESULTS

The thickness of myoid and ellipsoid zone, choroid and the mean retinal sensitivity were significantly smaller in diabetic group than that in controls (all P values < 0.05). Besides, thinner choroid and outer retina was associated with the decreased retinal sensitivity，especially in diabetic patients (r = 0.377, P = 0.048; r = 0.401, P = 0.034; respectively). Final multiple regression models showed the outer retinal thickness (ORT) (P = 0.033), choroidal thickness (P = 0.003) and the interaction between ORT and choroidal thickness (P = 0.001) were significant predictors to retinal sensitivity.

CONCLUSIONS

Thinning of choroid and outer retina were significantly correlated with reduced retinal sensitivity, which indicate outer retina and choroid might be potential imaging markers for evaluation of visual function related to neural impairment in type 2 diabetic patients without or in the early stage of diabetic retinopathy.

Optical coherence tomography biomarkers indicating visual enhancement in diabetic macular edema resolved through anti-VEGF therapy: OCT biomarkers in resolved DME

PURPOSE

to investigate the structural features and extended visual results in eyes affected by diabetic retinopathy (DR) and diabetic macular edema (DME) that have been successfully treated with anti-vascular endothelial growth factor (VEGF) therapy.

METHODS

Individuals (39 eyes of 39 patients) who had undergone long-term follow-up and demonstrated evidence of resolved DME after at least 2 years of follow-up following the initiation of anti-VEGF therapy were included. During the ""study visit"", structural OCT scans were examined to assess qualitative features indicative of neuroretina or retinal pigment epithelium distress. Additionally, a quantitative assessment of the inner and outer retinal thicknesses was conducted for topographical analysis.

RESULTS

The most robust qualitative association observed with BCVA at the "study visit" was linked to the presence of DRIL (p = 0.043) and the appearance of the ELM. (p = 0.045). Regarding quantitative parameters, a strong correlation was noted between the visual acuity during the "study visit" and the foveal and parafoveal thicknesses of both the inner and outer retina (p < 0.001).

CONCLUSIONS

Changes in the status of ELM, the presence of DRIL, and the thicknesses of the foveal and parafoveal regions can act as OCT biomarkers, signifying prolonged visual improvements in eyes that have experienced resolved DME after undergoing anti-VEGF therapy.

In silico identification and functional prediction of differentially expressed genes in South Asian populations associated with type 2 diabetes

Type 2 diabetes (T2D) is one of the major metabolic disorders in humans caused by hyperglycemia and insulin resistance syndrome. Although significant genetic effects on T2D pathogenesis are experimentally proved, the molecular mechanism of T2D in South Asian Populations (SAPs) is still limited. Hence, the current research analyzed two Gene Expression Omnibus (GEO) and 17 Genome-Wide Association Studies (GWAS) datasets associated with T2D in SAP to identify DEGs (differentially expressed genes). The identified DEGs were further analyzed to explore the molecular mechanism of T2D pathogenesis following a series of bioinformatics approaches. Following PPI (Protein-Protein Interaction), 867 potential DEGs and nine hub genes were identified that might play significant roles in T2D pathogenesis. Interestingly, CTNNB1 and RUNX2 hub genes were found to be unique for T2D pathogenesis in SAPs. Then, the GO (Gene Ontology) showed the potential biological, molecular, and cellular functions of the DEGs. The target genes also interacted with different pathways of T2D pathogenesis. In fact, 118 genes (including HNF1A and TCF7L2 hub genes) were directly associated with T2D pathogenesis. Indeed, eight key miRNAs among 2582 significantly interacted with the target genes. Even 64 genes were downregulated by 367 FDA-approved drugs. Interestingly, 11 genes showed a wide range (9-43) of drug specificity. Hence, the identified DEGs may guide to elucidate the molecular mechanism of T2D pathogenesis in SAPs. Therefore, integrating the research findings of the potential roles of DEGs and candidate drug-mediated downregulation of marker genes, future drugs or treatments could be developed to treat T2D in SAPs.

Prevalence and associated factors of diabetic retinopathy among people with diabetes screened using fundus photography at a community diabetic retinopathy screening program in Nepal

BACKGROUND

This study aimed to assess the prevalence and associated factors of diabetic retinopathy (DR) and vision threatening DR (VTDR) among people with diabetes screened using fundus photography in Nepal.

METHODS

This is a retrospective study among people with diabetes presented for DR screening using fundus photography from 2013 to 2019. Detailed demographics, duration of diabetes, medical history, visual acuity, and grading of DR on fundus photography were analyzed. Fundus camera used in the study were;Topcon digital fundus camera 900 CXR and digital portable fundus cameras (Nidek-10 portable non-mydriatric fundus camera; Versacam & Trade & Alpha, France), and a Zeiss portable fundus camera (Zeiss Visucout 100). Macula centred and disc centred 45 degree two images were taken from each eye. Pupil were dilated in cases where there was media haze in un-dilated cases. DR was graded using early treatment diabetic retinopathy study criteria. The images were graded by fellowship trained retina specialist. DR prevalence included any DR changes in one or both eyes.

RESULTS

Total of 25,196 patients with diabetes were enrolled. Mean age was 54.2 years with Standard Deviation (S.D):12.9 years, ranging from 6 years to 97 years. Type 1 and type 2 diabetes comprised of 451 people (1.79%) and 24,747 (98.21%) respectively. Overall, 1.8% of the images were un-gradable. DR prevalence was 19.3% (95% Confidence Interval (CI): 18.8 - 19.7%). DR prevalence in type 1 and type 2 diabetes was 15.5% (95% CI: 12.5 - 18.6%) and 19.3% (CI: 18.8 - 19.8%) respectively. Clinically significant macular edema (CSME) was found in 5.9% (95% CI: 5.6-6.2%) and VTDR in 7.9% (95% CI: 7.7-8.3%). In multivariate analysis, our study revealed strong evidence to suggest that there is meaningful association between DR and VTDR with duration of diabetes, diabetic foot, diabetic neuropathy, agriculture occupation, those under oral hypoglycaemic agents or insulin or both as compared to those under diet only, and presenting visual acuity > 0.3LogMAR.

CONCLUSION

Prevalence and associated factors for DR and VTDR were similar to other DR screening programs in the region. Emphasis on wider coverage of DR screening could help for timely detection and treatment of STDR to avoid irreversible blindness.

Polyphenols target miRNAs as a therapeutic strategy for diabetic complications

MiRNAs are a large group of non-coding RNAs which participate in different cellular pathways like inflammation and oxidation through transcriptional, post-transcriptional, and epigenetic regulation. In the post-transcriptional regulation, miRNA interacts with the 3'-UTR of mRNAs and prevents their translation. This prevention or dysregulation can be a cause of pathological conditions like diabetic complications. A huge number of studies have revealed the association between miRNAs and diabetic complications, including diabetic nephropathy, cardiomyopathy, neuropathy, retinopathy, and delayed wound healing. To address this issue, recent studies have focused on the use of polyphenols as selective and safe drugs in the treatment of diabetes complications. In this article, we will review the involvement of miRNAs in diabetic complications' occurrence or development. Finally, we will review the latest findings on targeting miRNAs by polyphenols like curcumin, resveratrol, and quercetin for diabetic complications therapy.

Lycium barbarum polysaccharides attenuates high glucose-induced diabetic retinal angiogenesis by rescuing the expression of miR-15a-5p in RF/6A cells

ETHNOPHARMACOLOGICAL RELEVANCE

Lycium barbarum L., a classical traditional Chinese Medicine, has long been used to treat ocular diseases. Lycium barbarum polysaccharides (LBP) is an effective component of Lycium barbarum L. with a wide range of pharmacological activities. This research aims to investigate the inhibition of high glucose-induced angiogenesis by LBP in RF/6A cells.

MATERIALS AND METHODS

A high-glucose-induced angiogenesis model was established using monkey retinal vascular endothelial (RF/6A) cells. Different dosages administration times of LBP and glucose concentrations were tested. Under the optimized conditions, RF/6A cells were treated with LBP for 48 h, followed by another 48-h culture in high glucose (25 mmol/L) medium. The effect and mechanism of LBP were investigated following the treatment.

RESULTS

The expression of miR-15a-5p and miR-15a-3p in RF/6A cells decreased significantly after 48 h of 25 or 50 mmol/L high glucose treatment. The expression of miR-15a-5p was higher than that of miR-15a-3p. Mimic-miR-15a-5p or 600 mg/L LBP could increase the apoptosis of cells and the total length of vascular branches. The expression of VEGFA, VEGFR2, and ANG2 proteins was reduced, while the expression of ANG1 protein was elevated. Expression of ASM mRNA and protein was also inhibited.

CONCLUSIONS

LBP attenuates diabetic retinal angiogenesis by rescuing the expression of miR-15a-5p in RF/6A cells.