Current Eye Research最新文献

Purpose: To evaluate the expression differences of tear lymphotoxin-α (LT-α), total immunoglobulin E (IgE), and matrix metalloproteinase-9 (MMP-9) in seasonal/perennial allergic conjunctivitis-associated dry eye (S/PAC-DE) and their clinical relevance, probing the underlying pathogenesis of S/PAC-DE.

Methods: This study enrolled 37 S/PAC-DE patients, 23 dry eye (DE) patients, and 24 healthy controls (HC). Assessing the clinical parameters, tear LT-α, total IgE, MMP-9, and nine other inflammatory cytokines in the three groups. Correlations between tear cytokines and clinical parameters were also analyzed.

Results: Tear LT-α levels were significantly lower in S/PAC-DE compared to DE and HC groups. Tear total IgE, TNF-α, and MMP-9 levels were significantly upregulated in the S/PAC-DE group than those in the DE (all p < 0.001) and HC groups (p = 0.005, p < 0.001, and p = 0.048). In the S/PAC-DE group, total IgE was positively correlated with MMP-9 (r = 0.652, p = 0.008). Total IgE and LT-α were positively correlated in the DE group (r = 0.498, p = 0.016), while the two showed a negative correlation trend in the S/PAC-DE group (r=-0.272, p = 0.103). LT-α was positively correlated with tear film break-up time and negatively correlated with corneal fluorescein staining score in both the S/PAC-DE and DE groups.

Conclusions: In the S/PAC-DE co-morbid state, the inhibition of tear LT-α expression and the upregulation of the pro-inflammatory cytokines total IgE, TNF-α, and MMP-9 may collectively contribute to the disruption of the ocular surface epithelial barrier, further promoting and exacerbating DE. Additionally, the differences in correlation between LT-α and total IgE in the S/PAC-DE and common DE patients may be related to the distinct ocular immune microenvironments.

Purpose: This study aims to elucidate the causal relationships and shared genetic architecture between metabolic-associated diseases and risk factors-including hypertension, type 1 diabetes (T1D), type 2 diabetes (T2D), low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and body mass index (BMI)-and primary vision-threatening eye disorders, involving glaucoma, cataracts, refractive disorders, and age-related macular degeneration (AMD).

Methods: We analyzed genome-wide association study (GWAS) summary statistics from > 500 000 individuals of European ancestry in the FinnGen, UK Biobank, and MRC-IEU databases to ensure adequate sample size. Linkage disequilibrium score regression (LDSC) was applied to estimate genetic correlations, while two-sample Mendelian randomization (MR) was performed to assess causal effects. Furthermore, a bidirectional Mendelian Randomization was further conducted to examine the directionality of associations between hypertension and cataracts.

Results: This study was the first to reveal genetic correlations and causal effects of hypertension on cataracts, particularly senile cataracts. MR analysis provided evidence that hypertension is causally associated with an increased risk of cataracts, particularly senile cataract, whereas the reverse association was not supported. Additionally, LDL cholesterol was suggested as a protective factor for AMD, while HDL cholesterol was associated with an increased risk. The LDSC analysis also indicated a suggestive genetic correlation between T2D and both cataracts and glaucoma, but not for T1D.

Conclusion: This study provides comprehensive evidence of genetic correlations and potential causal relationships between metabolic-associated conditions and major eye diseases contributing to vision loss.

Purpose: The decision when to operate cataract can be difficult when there are subjective visual complaints but visual acuity is intact. Straylight measurements can help to improve surgical decision making in this group of patients. It is however unclear if pupil size can affect straylight when cataract is present. In this study we investigate the effects of pupil size on intra-ocular straylight in patients with multiple types of cataract.

Methods: A total of 85 eyes from 51 participants were measured, with an average age of 66 years. Straylight was measured before and after pharmacologic mydriasis with the Oculus C-Quant device. Cataract was graded using the LOCS III classification system. Exploratory analysis using retro-illumination slit-lamp photography was performed to divide between central and peripheral lens opacities.

Results: Mean straylight both before and after dilation was 1.57 log(s). Reliable individual effects from dilation ranged between -0.42 and +0.48 log(s). No significant differences were found between cataract subtype groups using mixed model analysis. In nuclear cataract mean straylight levels were 1.71 log(s) undilated and 1.66 log(s) dilated. Mean straylight in cortical cataract was 1.38 log(s) undilated and 1.51 log(s) dilated. Centrally and peripherally located cataracts showed a mean change after mydriasis of -0.08 and +0.07 log(s), respectively.

Conclusions: Straylight after pupil dilation showed varying degrees of change, with a tendency to increase in cortical cataract and decrease in nuclear cataract. However, in all forms of cataract both large increases and decreases can be found. These changes were found to be repeatable and reliably measured. Centrality determination from retro-illumination photography can only partly predict these changes.

Purpose: This review provides an outcome-oriented, comprehensive summary of published works on the topic of repurposing the anterior lens capsule (ALC) in various subfields of ophthalmic surgery. Covering a broad spectrum of studies ranging from pre-clinical experiments on animal models to blinded prospective clinical trials involving patients.

Materials and methods: National Institute of Health (NIH) and COCHRANE libraries were comprehensively searched for published works covering the topic of ALC utilization in corneal, retinal, and glaucoma surgical procedures. Studies covering the topic of ALC use unrelated to ophthalmic surgical trials were excluded. A total of 15 studies were included based on the search criteria. Patient follow-up was limited to 18 months. Primary and secondary post-surgical outcomes were evaluated to assess the surgical effectiveness and complication risk of ALC use compared to alternative surgical techniques.

Results: ALC is a viable ophthalmic tissue for prospective use in ophthalmic surgery. Despite the limited number of studies conducted on the topic, the results presented have shown promise. Three studies demonstrated superior post-surgical outcomes in ALC-utilizing procedures compared to other ophthalmologic interventions. Remaining studies included in this review have demonstrated potential equivalence of outcomes after ALC-utilizing surgeries to established surgical methods without presenting new limitations and complications.

Conclusions: ALC is an abundant, routinely discarded tissue during cataract surgery. It possesses unique properties of acellularity, optical transparency, and immunologic nativity to the human eye, which enables it to be an excellent donor tissue for ophthalmic surgeries ranging from corneal defect management to prolonging the longevity of anti-glaucoma filtering blebs. The use of ALC autografts in ophthalmic surgery allows for augmentation of standard procedures in phakic patients, delivering satisfactory outcomes and potentially reducing costs. Further research into ALC collection, processing, and long-term storage is needed to enable ALC allograft use in pseudophakic and aphakic patients.

Purpose: This study aims to investigate the longitudinal changes in ocular biometry in mice treated with exogenous all-trans retinoic acid (atRA) and make comparisons with the lens-induced myopia (LIM) model.

Materials and methods: Male C57BL/6J mice were administered 10 µl of atRA (1 milligram [mg]/milliliter [mL]) every other two days via peribulbar injection. The LIM group received monocular -30D lenses. Ocular biometrics were measured on Days 0, 3, 6, 10, and 15 using swept-source optical coherence tomography. Scleral thickness (ST) and retinal arc length (RAL) were measured on histological sections.

Results: Both exogenous atRA and negative lenses induced longer axial length (AL) from Day 3 and thinner retinal thickness (RT) from Day 6 (all p < 0.05). An increase in vitreous chamber depth (VCD) was noted from Day 3 in atRA-Treated (p = 0.001) eyes and from Day 6 in LIM-Treated eyes (p < 0.001). The interocular difference in lens thickness (LT) varied significantly over time (p = 0.004) in the atRA group. The LT to AL ratios (LT/AL) for atRA-Treated eyes were notably higher than those for the LIM eyes on Days 10 and 15 (all p < 0.05). The VCD to AL ratios (VCD/AL) were comparable between the two groups, with notable declines observed in the late stage (all p < 0.01). Additionally, both treatment groups showed similarly reduced ST and larger RAL than untreated eyes.

Conclusions: Mice treated with exogenous atRA demonstrated comparable longitudinal ocular biometric alterations to the LIM model, except for the relatively thicker lenses.

Purpose: Growing evidence implicates gut microbiota dysbiosis in the pathogenesis of diabetic retinopathy (DR). This study aimed to investigate the associations between dietary index for gut microbiota (DI-GM), a novel metric reflecting gut microbiota composition and diversity, and DR risk, as well as to examine the mediating role of inflammatory and oxidative stress biomarkers.

Methods: This cross-sectional study analyzed 4,003 diabetic individuals (mean age 59 years, 51.21% men) from 1999-2018 National Health and Nutrition Examination Survey. DI-GM was derived from self-reported 24-hour dietary recalls. Mediation analysis was used to investigate the role of inflammation (neutrophils, lymphocytes, and alkaline phosphatase) and oxidative stress (gamma-glutamyl transferase, uric acid, and total bilirubin) biomarkers in the effects of DI-GM on DR prevalence. Binary logistic regression analysis was adopted to explore the association of DI-GM and DR prevalence.

Results: The prevalence of DR was 19.64%. Multivariate-adjusted odds ratio (95% confidence intervals) for the association between DI-GM and DR prevalence was 0.73 (0.68-0.79). Restricted cubic spline curves showed a non-linear inverse relationship between DI-GM and DR prevalence. Subgroup analysis indicated that the association between DI-GM and DR prevalence was more pronounced in participants with a body mass index > 25 kg/m². Alkaline phosphatase and total bilirubin mediated 10.27% and 9.45% of the effects of DI-GM scores on DR prevalence.

Conclusions: Adherence to microbiota-friendly diet was associated with a lower DR prevalence, especially among individuals with overweight or obesity. Alkaline phosphatase and total bilirubin may be associated with the gut microbiota-retina interactions in DR.

Purpose: To investigate the variations in retinal thickness and choroidal thickness at different distances from the optic disk in the guinea pigs.

Methods: Twenty 3-week-old pigmented guinea pigs were randomly divided into a normal control group and a lens-induced myopia group. The normal control group received no intervention, while the lens-induced myopia group wore a -10D lens on the right eye to induce myopia and a 0D lens on the left eye as control. Refraction, axial length, corneal curvature radius, vitreous chamber depth, retinal thickness, and choroidal thickness were measured at baseline, 2 and 4 weeks. Centered on the optic disk, concentric circles with radii of 1000, 1500, 2000, and 2500 μm were drawn using Image J software (Bethesda, MD) to partition the retina and choroid.

Results: After 4 weeks, lens-induced myopia-eyes showed lower refraction (lens-induced myopia vs. normal control, -1.38 ± 0.91D vs. 2.64 ± 0.76D, p < 0.0001), retinal thickness (lens-induced myopia vs. normal control, 149.14 ± 4.64 μm vs. 159.63 ± 4.64 μm, p < 0.0001) and choroidal thickness (39.07 ± 3.30 μm vs. 45.80 ± 5.32 μm, p < 0.01), and increased axial length (lens-induced myopia vs. normal control, 8.34 ± 0.20 mm vs. 8.01 ± 0.16 mm, p < 0.0001) and vitreous chamber depth (lens-induced myopia vs. normal control, 3.87 ± 0.11 mm vs. 3.50 ± 0.11 mm, p < 0.0001) compared with the normal control group and Fellow-eye. At week 4, retinal thickness at all positions of the lens-induced myopia-eye differed from normal control and Fellow-eye, while choroidal thickness differed only at 1500 μm and 2000 µm. Thinning of retinal thickness and choroidal thickness are both at distances of 1500 μm and 2000 μm. Mean retinal thickness and choroidal thickness correlated positively with refraction, but the changes in retinal thickness and choroidal thickness at each position are not correlated with the changes in RE.

Conclusion: The structural changes in the retina and choroid during myopia progression are region-specific rather than uniform across the posterior pole.

Purpose: Uveitis is a irreversible blinding eye disease with unknown mechanism. The imbalance of Treg/Th17 caused by the interaction of genetics and environment is the core mechanism of the occurrence and development of uveitis. We aimed to confirm that intestinal immune imbalance aggravates uveitis.

Methods: The experimental autoimmune uveitis (EAU) model was established by immunizing mice with IRBP1-20. Flow cytometry was used to detect the expression of CD4 + T lymphocytes, dendritic cells and memory CD4 + T cells in the intestinal lamina propria on days 7 and 14 of induction. Fitc-dextran test was used to detect intestinal permeability, and RT-PCR was used to detect the expression of occludin and ZO-1 in intestinal epithelial cells. The ROS level in intestinal epithelial cells was detected by ROS probe, and the expression levels of NLRP3 inflammasome, caspase-1 and IL-1β in intestinal epithelial cells were detected by WB. In addition, antioxidant was administered via intraperitoneal injection to induce protection against EAU, clinical scores were used to assess disease progression. Flow cytometry was used to detect the proportion of Th17 and Treg cells in the mesenteric draining lymph nodes.

Results: In the early stages of EAU, CD4+ T cells, dendritic cells, and memory CD4+ T cells were observed in the intestinal lamina propria. Additionally, dysfunction of the intestinal epithelial barrier was characterized by increased FITC-dextran permeability and decreased occludin and ZO-1 expression, highlighting its role in the pathogenesis of EAU. Notably, we also detected elevated levels of ROS, NLRP3 inflammasome, caspase-1, and IL-1β in the intestinal epithelium of EAU mice. Antioxidant treatment in EAU mice demonstrated a protective effect by inhibiting the expression of ROS, NLRP3, caspase-1, and IL-1β in intestinal epithelial cells.

Conclusions: Activation of the intestinal ROS-NLRP3 axis leads to a disruption in the balance between Teff cells and Treg cells, contributing to the pathogenesis of uveitis.

Purpose: To determine whether conjunctival and retinal microcirculatory improvements induced by Ocufolin^® supplementation are independently regulated in mild non-proliferative diabetic retinopathy (MDR).

Methods: Eighteen MDR patients (18 eyes) received Ocufolin^® for six months. Conjunctival flow rate (Q) and vessel density (CVD) were measured using a functional slit‑lamp biomicroscope. Retinal blood flow (RBF) and vessel densities in the superficial (SVP), deep (DVP), and total retinal vascular network (RVN) were obtained using retinal function imaging and OCT angiography. Measurements were taken at baseline, 4 months, and 6 months. Mean values from both eyes were averaged and correlations between conjunctival and retinal parameters were analyzed.

Results: Q increased significantly from 91.71 ± 34.53 pl/s at baseline to 119.81 ± 40.75 pl/s at 4 months and 138.70 ± 75.37 pl/s at 6 months (p < 0.05). RBF also rose from 2.27 ± 0.71 nl/s to 2.78 ± 1.00 nl/s and 3.20 ± 0.89 nl/s (p < 0.05). Vessel densities (CVD, SVP, DVP, RVN) did not change significantly (p > 0.05). RBF and Q were correlated at baseline, but not at the fourth or sixth month. No other significant correlations were found between conjunctival (Q or CVD) and retinal (RBF or vessel density) metrics at any time point (p > 0.05).

Conclusion: As the first study to assess post‑supplementation correlations between conjunctival and retinal microcirculation in MDR, the study's findings show that Ocufolin^® improved blood flow in both tissues. These results support using conjunctival and retinal measurements as complementary biomarkers in MDR evaluation.