Current Eye Research最新文献

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.

Purpose: To develop a simple concept for deriving the central corneal radius (RC) from the keratometry (K) or simulated keratometry (SimK) radius (RS) and corneal asphericity (QC), and to show the differences RC-RS based on a large dataset of measurements from a modern anterior segment tomographer.

Methods: Comparing the local slopes of surface representations with a conoid and a reference sphere at the location of a keratometry measurement (diameter KD), RC and RC-RS can be derived as a function of RS, QC and KD. The differences RC-RS were evaluated for a large dataset containing measurements from the Casia 2 tomographer made before cataract surgery.

Results: Depending on QC and KD, RC could deviate from the measured RS by up to 0.1 mm. With prolate corneas RS overestimates RC, and with oblate corneas RS underestimates RC. For example, with a typical cornea with RS = 7.7 mm and QC = -0.22 and a keratometer measuring at KD = 3 mm the central cornea is 0.0322 mm steeper (RC = 7.6678 mm) compared to keratometric measurement. Based on the dataset, the 95% confidence interval of RC-RS with KD = 3 mm was -0.0976 to +0.0265 mm.

Conclusions: For corneal representations with a conoid surface or where central corneal radius is required e.g. for paraxial calculations, the keratometric radius of curvature could easily be converted to the central radius based on corneal asphericity and the keratometric zone diameter. With large positive or negative values of QC the differences RC-RS could be clinically relevant.

Purpose: Herpes simplex keratitis (HSK) remains a major global cause of corneal blindness, with frequent viral recurrences leading to progressive corneal damage despite the use of antivirals and corticosteroids. This review aims to highlight the limitations of current therapeutic strategies and evaluate emerging prognostic and diagnostic biomarkers that may enable earlier detection, improved disease monitoring, and personalized treatment approaches in HSK.

Methods: A comprehensive review of recent literature was conducted, focusing on studies examining the pathophysiology of HSK, current treatment challenges, and the role of emerging biomarkers in viral entry, replication, inflammation, and corneal tissue remodeling. Particular emphasis was placed on evaluating the clinical utility of aptamer-based detection tools, heparanase activity assays, and matrix metalloproteinase profiles in diagnosing and predicting HSK severity and recurrence.

Results: Evidence indicates that while antivirals and corticosteroids remain essential for managing acute HSK episodes, their effectiveness is limited by high recurrence rates and the adverse effects associated with prolonged steroid use. Biomarkers such as aptamers, heparanase, and matrix metalloproteinases show strong potential as tools for early detection, monitoring viral activity, and assessing disease severity. These biomarkers correlate with key pathogenic mechanisms, suggesting their utility in therapeutic strategies.

Conclusion: Conventional HSK management is hindered by treatment-related complications. Integrating these biomarkers into clinical practice may help preserve corneal structure, and ultimately improve visual outcomes for patients with HSK.

Purpose: The purpose of this study was to compare the visual function, using standard optometric clinical procedures, between children with ADHD and healthy controls, and to examine the mediating role of psychostimulant medication. This work aims to provide clinically relevant evidence that may contribute to a better management of children with ADHD in eye care settings.

Methods: A total of 112 children aged 6 to 14 years old were divided into three different groups: 58 non-medicated ADHD children, 22 medicated ADHD children, and 32 age-matched controls. A series of visual variables commonly assessed in clinical practice (i.e. refractive error, visual performance, accommodation, and binocular system) were measured according to standard procedures.

Results: Statistically significant differences were observed for contrast sensitivity (p-value = 0.014), with the control group showing better results. Regarding accommodative and binocular parameters, only the accommodative facility showed a statistically significant (p = 0.048) tendency toward a worse ability to change accommodative focus in children with ADHD compared to controls. Psychostimulant treatment did not have any effect on visual function (p > 0.05 in all cases).

Conclusions: From all the variables assessed, only accommodation facility and contrast sensitivity appear to differ from the control group, and these appear to be independent of psychostimulant treatment in children with ADHD.

Purpose: To investigate innate and adaptive immune responses in allergic conjunctivitis induced by simultaneous sensitization with Orchard grass and Alternaria antigens.

Materials and methods: An experimental allergic conjunctivitis (EAC) mouse model was developed by instilling mixed antigen solutions of Orchard grass and Alternaria antigens after sensitization via intraperitoneal administration of a mixed antigen solution. BALB/cj mice were divided into four groups based on sensitization and number of antigen eye drop instillations: (1) A1 group (single instillation without intraperitoneal administration), (2) S1 group (single instillation with intraperitoneal administration), (3) M1 group (three instillations with intraperitoneal administration), (4) C group (negative control with receiving neither instillation nor intraperitoneal administration). Clinical observations and histological examinations for eosinophils were performed, and eosinophil density in the conjunctival tissue was quantified. Gene expression levels of thymic stromal lymphopoietin (TSLP), interleukins (IL-4, IL-5, IL-13, IL-16, and IL-33), and CCL11/eotaxin-1 in the conjunctiva were evaluated using real-time reverse transcriptase polymerase chain reaction.

Results: The clinical symptoms of allergic conjunctivitis were observed in the A1, S1, and M1 groups. Eosinophil density at 1 h after the last instillation was significantly higher in the A1, S1, and M1 groups compared to the C group (p < 0.01), with the M1 group showing higher density than the S1 group (p < 0.01). Conjunctival TSLP messenger RNA (mRNA) expression levels were increased in the sensitized (S1 and M1) groups compared to the C group (p < 0.01 and p < 0.05, respectively), with the M1 group exhibiting higher expression than the S1 group (p < 0.01). Additionally, mRNA expression levels of IL-16 and CCL11 in the M1 group were significantly higher than those in the A1 group.

Conclusions: Allergic conjunctivitis induced by Orchard grass and Alternaria antigens is characterized by early eosinophil infiltration, and TSLP upregulation exacerbates the allergic inflammation in the conjunctiva.

Purpose: To analyze proteoglycans and other extracellular matrix macromolecules from normal (NL) and keratoconus (KC) human corneas.

Methods: Corneas from eye banks (NL) and penetrating keratoplasty (KC) were obtained. Halves of the corneas were fixed and prepared for immunofluorescence using confocal microscopy; the other halves were subjected to macromolecule extraction with GuHCl for protein quantification, macromolecule identification by polyacrylamide gel electrophoresis with sodium dodecyl sulfate (SDS-PAGE) and western blotting, and quantification by enzyme-linked immunosorbent assay (ELISA).

Results: In the study population (N = 8 for NL and N = 12 for KC), there was no difference in sex, laterality, wet weight, or preservation time, but only in age. Western blotting detected keratan sulfate (KS), decorin, and lumican in both groups, with structural differences in decorin in the KC group. The mean protein concentration by corneal wet weight was significantly lower in the KC group. The mean concentrations of decorin, lumican, and KS did not show any difference between the groups when normalized by wet weight but showed a higher concentration in the KC group when normalized by μg of extracted protein. Immunofluorescence analysis revealed a similar macromolecular distribution among the groups.

Conclusions: In corneas with KC, non-collagenous proteins decreased without affecting decorin, lumican, or KS levels, which were relatively increased. In addition, decorin was highly glycosylated.

Purpose: Dry eye disease (DED) is a prevalent ocular surface condition characterized by tear film instability and inflammation, significantly impacting patients' quality of life. While the Schirmer test remains a key diagnostic tool, Schirmer strips are increasingly used for tear fluid collection in metabolomics studies aimed at, e.g. identifying biomarkers for DED. However, both pre-analytical and analytical variables inherent to Schirmer strip use can compromise data integrity and hamper reproducibility.

Methods: For this review, the PubMed database and Google Scholar were searched for published human studies in English relevant to pre-analytical and analytical aspects of tear metabolomics, especially from dry eye patients, when tear samples were collected with Schirmer strips.

Results: This article discusses the critical pre-analytical factors, including variability in Schirmer strip materials, tear sampling techniques, storage conditions, and potential contamination, that influence metabolomic data quality. Analytical considerations are also examined, with particular focus on volume-adjusted extraction protocols that address tear volume variability.

Conclusion: We conclude that standardized guidelines for Schirmer strip use, covering material selection, sampling protocols, storage, and extraction, are urgently needed to advance tear metabolomics as a reliable clinical and research tool. Future research should focus on validating these recommendations in multi-center studies, exploring inter-individual variability, and developing innovative analytical workflows to optimize metabolite recovery and quantification. Such efforts will enhance the translational potential of tear metabolomics, paving the way for biomarker discovery and improved management of DED.