Association of tear matrix metalloproteinase 9 immunoassay with signs and symptoms of dry eye disease: A cross-sectional study using qualitative, semiquantitative, and quantitative strategies

Management of Oxidative Stress and Inflammation in Patients with Symptomatic Dry Eye Disease Treated with a Preservative-Free Ophthalmic Emulsion Combining Alpha-Lipoic Acid and High Molecular Weight Sodium Hyaluronate

INTRODUCTION

This study aimed to explore the beneficial effect of a preservative-free (PF) emulsion eyedrop combining high molecular weight sodium hyaluronate (HMW-HA) and alpha-lipoic acid on oxidative stress and ocular surface inflammation in patients with dry eye disease (DED).

METHODS

In this prospective exploratory study, patients with moderate to severe DED symptoms were treated with the study eyedrop, 4-6 times/day for 1 month. Two visits were scheduled: baseline (D0) and after 35 days (D35). The following parameters were assessed: quality of life (OSDI score); superoxide dismutase (SODase) concentration in tears; goblet cell (GC) density (impression cytology); conjunctival hyperemia (Efron scale); corneal, conjunctival, and eyelid staining (Oxford scale); and meibomian gland (MG) blockage. Data were compared between D0 and D35 in subgroups of patients with a significant abnormality of the study outcome at baseline.

RESULTS

Forty patients were involved, with a highly significant improvement of OSDI score at D35. The mean concentration of SODase significantly increased by 3.2 and 2.4 times for SODase1 and SODase2 respectively, in patients with deficient SODase at baseline. In patients with abnormal GC density at baseline, GC count increased by five times at D35. Conjunctival hyperemia and corneal staining scores significantly improved in the subpopulation of patients with a baseline grade ≥ 2. Eyelid margin staining was significantly reduced at D35 in patients with significant abnormalities at baseline. A significant reduction of MG obstruction was shown in the lower eyelid in patients with significant blockage at baseline.

CONCLUSION

The use of a PF ophthalmic emulsion combining alpha-lipoic acid and HMW-HA shows a beneficial effect on the ocular surface through the improved quality of life score. Noteworthy, patients presenting high oxidative and inflammatory conditions experienced significant improvement in oxidative stress and inflammation markers; this synergic effect is likely due to the well-known properties of alpha-lipoic acid and HMW-HA, enhancing DED management.

TRIAL REGISTRATION

ISRCTN.com identifier, 17861788.

Biodegradable 3D-Printed Conjunctival Inserts for the Treatment of Dry Eyes

PURPOSE

To fabricate 3D-printed, biodegradable conjunctival gelatin methacrylate (GelMA) inserts that can release polyvinyl alcohol (PVA) when exposed to an ocular surface enzyme.

METHOD

In this work, biodegradable conjunctival inserts were 3D-printed using a stereolithography-based technique. The release of PVA from these insert formulations (containing 10% GelMA and 5% PVA (P-Gel-5%)) was assessed along with different mathematical models of drug release. The biodegradation rates of these inserts were studied in the presence of a tear-film enzyme (matrix metalloproteinase-9; MMP9). The morphology of the inserts before and after enzymatic degradation was monitored using scanning electron microscopy.

RESULTS

The 3D-printed P-Gel-5% inserts formed a semi-interpenetrating network, which was mechanically stronger than GelMA inserts. The PVA release graphs demonstrate that at the end of 24 h, 222.7 ± 20.3 µg, 265.5 ± 27.1 µg, and 242.7 ± 30.4 µg of PVA were released when exposed to 25, 50, and 100 µg/mL of MMP9, respectively. The release profiles of the P-Gel-5% containing hydrogels in the presence of different concentrations of MMP9 showed the highest linearity with the Korsmeyer-Peppas model. The results suggest that the degradation rate over 24 h is a function of MMP9 enzyme concentration. Over 80% of P-Gel-5% inserts were degraded at the end of 8 h, 12 h, and 24 h in the presence of 100, 50, and 25 µg/mL MMP9 enzyme solutions, respectively.

CONCLUSIONS

These results demonstrate the potential for 3D printing of GelMA for use as conjunctival inserts. These inserts could be used to deliver PVA, which is a well-known therapeutic agent for dry eye disease. PVA release is influenced by multiple mechanisms, including diffusion and enzymatic degradation, which is supported by morphological studies and biodegradation results.

Efficacy of Topical 0.05% Cyclosporine A for Ocular Surface Disease Related to Topical Anti-Glaucoma Medications

Purpose: We aimed to determine the therapeutic efficacy of 0.05% topical cyclosporine A (CsA) for chronic ocular surface disease (OSD) in patients using benzalkonium chloride (BAK)-preserved antiglaucoma eye drops. Methods: A prospective, randomized, paired-eye, controlled clinical trial was conducted with participants who had been instilling at least one BAK-preserved topical antiglaucoma drug in both eyes for at least 6 months. Topical CsA was only applied in randomly selected unilateral eyes. Visual field (VF) indices, ocular surface parameters, tear meniscus height (TMH), and matrix metalloproteinase-9 (MMP-9) immunoassay were evaluated at baseline and at 2 and 4 months. Results: Seventy eyes from 35 participants were included in the study. The Schirmer I, tear breakup time, and TMH increased by 4.5 ± 8.6 mm (P < 0.01), 5.0 ± 5.3 s (P < 0.001), and 85.4 ± 159.0 μm (P < 0.01) in the treated eyes at 4 months from baseline, respectively. The ocular staining score and MMP-9 positivity in the treated eyes decreased by 2.2 ± 1.3 (P < 0.001) and 0.7 ± 0.9 points (P < 0.001), respectively, at 4 months. In untreated eyes, only TMH increased by 41.4 ± 92.1 μm (P = 0.016) from baseline to 4 months. In VF indices, the tracking failure frequency was 19.09% ± 21.62%, and the test duration was 336.0 ± 79.5 s in the treated eyes at 4 months, which were lower than 34.37% ± 23.13% (P < 0.001) and 375.9 ± 70.7 s (P < 0.05) in the nontreated eyes. Conclusion: Application of topical 0.05% CsA significantly improved the OSD parameters and the reliability indices of VF tests. This study was registered with the Clinical Research Information Service (CRIS) (number KCT0007124).

Using Network Pharmacology and Molecular Docking to Explore the Mechanism of Qiju Dihuang Pill against Dry Eye Disease

Background

Dry eye disease (DED) is a multifactorial disease of the ocular surface, which affects the quality of life and work efficiency of affected patients. The traditional Chinese medicine formula Qiju Dihuang Pill (QJDHP) has a good therapeutic effect on DED. However, the pharmacological mechanism is not clear.

Objective

To explore the mechanism of QJDHP in the treatment of DED based on network pharmacology.

Method

The active components in QJDHP were screened in Traditional Chinese Medicine Systems Pharmacology (TCMSP), and putative molecular targets of QJDHP were identified using the SwissTargetPrediction database. DED-related targets were screened by GeneCards and OMIM. We established protein-protein interaction (PPI) and core targets and corresponding active compound network by Cytoscape to identify the core targets and main compounds of QJDHP against DED. DAVID database was utilized for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. Molecular docking was used to evaluate the binding activity between key active compounds and core targets.

Results

The results of network pharmacology showed that 253 targets of QJDHP were related to DED. PPI network analysis showed the 18 core targets. The binding affinity of docking results ranged from -5.7 to -9.3 kcal/mol, indicating a good docking effect. The results of GO enrichment analysis showed that the mechanism of QJDHP in the treatment of DED mainly involved biological processes such as apoptosis, oxidative stress, response to estrogen, angiogenesis, and the regulation of transcription factors. KEGG analysis showed that QJDHP may be regulated by the TNF signaling pathway, Toll-like receptor signaling pathway, MAPK signaling pathway, and estrogen signaling pathway in the treatment of DED.

Conclusion

In this study, we demonstrated the multicomponent, multitarget, and multichannel action mechanism of QJDHP in the treatment of DED and provided a foundation for further drug development research.

Proteases and Their Potential Role as Biomarkers and Drug Targets in Dry Eye Disease and Ocular Surface Dysfunction

Dry eye disease (DED) is a multifactorial disorder that leads to ocular discomfort, visual disturbance, and tear film instability. DED is accompanied by an increase in tear osmolarity and ocular surface inflammation. The diagnosis and treatment of DED still present significant challenges. Therefore, novel biomarkers and treatments are of great interest. Proteases are present in different tissues on the ocular surface. In a healthy eye, proteases are highly regulated. However, dysregulation occurs in various pathologies, including DED. With this review, we provide an overview of the implications of different families of proteases in the development and severity of DED, along with studies involving protease inhibitors as potential therapeutic tools. Even though further research is needed, this review aims to give suggestions for identifying novel biomarkers and developing new protease inhibitors.

Reduced Tear Thrombospondin-1/Matrix Metalloproteinase-9 Ratio Can Aid in Detecting Sjögren's Syndrome Etiology in Patients with Dry Eye

Differentiating patients with Sjögren's syndrome (SS)‐associated dry eye from non‐SS dry eye is critical for monitoring and appropriate management of possible sight‐ or life‐threatening extraglandular complications associated with SS. We tested whether reduced tear levels of immunoregulatory thrombospondin (TSP)‐1, which also inhibits matrix metalloproteinase (MMP)‐9, would reflect SS pathogenesis aiding the identification of patients with SS‐dry eye. Total of 61 participants, including healthy controls (n = 20), patients with non‐SS dry eye (n = 20) and SS‐dry eye (n = 21) were enrolled prospectively. Tear TSP‐1 and MMP‐9 levels were measured using a custom magnetic bead‐based multi‐plex assay in a masked manner. Analyte concentrations were assessed further according to ocular surface and tear film parameters. Relative to median tear TSP‐1 (308 ng/ml) and MMP‐9 (1.9 ng/ml) levels in the control group, significantly higher proportion of patients with SS‐dry eye than non‐SS had lower tear TSP‐1 levels (55% vs. 29%, odds ratio [OR] = 3, 95% confidence interval [CI] = 1.64 to 5.35, p < 0.05) and higher tear MMP‐9 levels (65% vs. 24%, OR = 5.8, 95% CI = 4.46 to 19.81, p < 0.05), respectively. The tear TSP‐1/MMP‐9 ratio was significantly reduced in patients with SS‐dry eye compared to non‐SS (B = −2.36, 95% CI = −3.94 to −0.0.79, p < 0.05), regardless of tear MMP‐9 levels. Patients with a lower ratio were 2.3 times more likely to have SS (OR = 0.28, 95% CI = 0.1 to 0.75, p < 0.05). This ratio showed significant inverse correlations with clinical parameters (conjunctival and corneal staining scores). Our results denote that tear TSP‐1/MMP‐9 ratio can be useful in identifying patients with dry eye with underlying SS and used as a screening test.

The Role of Metalloproteinases and Their Tissue Inhibitors on Ocular Diseases: Focusing on Potential Mechanisms

Eye diseases are associated with visual impairment, reduced quality of life, and may even lead to vision loss. The efficacy of available treatment of eye diseases is not satisfactory. The unique environment of the eye related to anatomical and physiological barriers and constraints limits the bioavailability of existing agents. In turn, complex ethiopathogenesis of ocular disorders that used drugs generally are non-disease specific and do not act causally. Therefore, there is a need for the development of a new therapeutic and preventive approach. It seems that matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) have a significant role in the development and progression of eye diseases and could be used in the therapy of these disorders as pharmacological targets. MMPs and TIMPs play an important role in the angiogenesis, epithelial-mesenchymal transition, cell invasion, and migration, which occur in ocular diseases. In this review, we aim to describe the participation of MMPs and TIMPs in the eye diseases, such as age-related macular degeneration, cataract, diabetic retinopathy, dry eye syndrome, glaucoma, and ocular cancers, posterior capsule opacification focusing on potential mechanisms.