Therapeutic potential of valproic acid in advanced glaucoma: A pilot study

Addressing neurodegeneration in glaucoma: Mechanisms, challenges, and treatments

Glaucoma is the leading cause of irreversible blindness globally. The disease causes vision loss due to neurodegeneration of the retinal ganglion cell (RGC) projection to the brain through the optic nerve. Glaucoma is associated with sensitivity to intraocular pressure (IOP). Thus, mainstay treatments seek to manage IOP, though many patients continue to lose vision. To address neurodegeneration directly, numerous preclinical studies seek to develop protective or reparative therapies that act independently of IOP. These include growth factors, compounds targeting metabolism, anti-inflammatory and antioxidant agents, and neuromodulators. Despite success in experimental models, many of these approaches fail to translate into clinical benefits. Several factors contribute to this challenge. Firstly, the anatomic structure of the optic nerve head differs between rodents, nonhuman primates, and humans. Additionally, animal models do not replicate the complex glaucoma pathophysiology in humans. Therefore, to enhance the success of translating these findings, we propose two approaches. First, thorough evaluation of experimental targets in multiple animal models, including nonhuman primates, should precede clinical trials. Second, we advocate for combination therapy, which involves using multiple agents simultaneously, especially in the early and potentially reversible stages of the disease. These strategies aim to increase the chances of successful neuroprotective treatment for glaucoma.

What can we learn from a Chinese social media used by glaucoma patients?

PURPOSE

Our study aims to discuss glaucoma patients' needs and Internet habits using big data analysis and Natural Language Processing (NLP) based on deep learning (DL).

METHODS

In this retrospective study, we used web crawler technology to crawl glaucoma-related topic posts from the glaucoma bar of Baidu Tieba, China. According to the contents of topic posts, we classified them into posts with seeking medical advice and without seeking medical advice (social support, expressing emotions, sharing knowledge, and others). Word Cloud and frequency statistics were used to analyze the contents and visualize the keywords of topic posts. Two DL models, Bidirectional Long Short-Term Memory (Bi-LSTM) and Bidirectional Encoder Representations from Transformers (BERT), were trained to identify the posts seeking medical advice. The evaluation matrices included: accuracy, F1 value, and the area under the ROC curve (AUC).

RESULTS

A total of 10,892 topic posts were included, among them, most were seeking medical advice (N = 7071, 64.91%), and seeking advice regarding symptoms or examination (N = 4913, 45.11%) dominated the majority. The following were searching for social support (N = 2362, 21.69%), expressing emotions (N = 497, 4.56%), and sharing knowledge (N = 527, 4.84%) in sequence. The word cloud analysis results showed that ocular pressure, visual field, examination, and operation were the most frequent words. The accuracy, F1 score, and AUC were 0.891, 0.891, and 0.931 for the BERT model, 0.82, 0.821, and 0.890 for the Bi-LSTM model.

CONCLUSION

Social media can help enhance the patient-doctor relationship by providing patients' concerns and cognition about glaucoma in China. NLP can be a powerful tool to reflect patients' focus on diseases. DL models performed well in classifying Chinese medical-related texts, which could play an important role in public health monitoring.

Immunomodulatory and Antioxidant Drugs in Glaucoma Treatment

Glaucoma, a group of diseases characterized by progressive retinal ganglion cell loss, cupping of the optic disc, and a typical pattern of visual field defects, is a leading cause of severe visual impairment and blindness worldwide. Elevated intraocular pressure (IOP) is the leading risk factor for glaucoma development. However, glaucoma can also develop at normal pressure levels. An increased susceptibility of retinal ganglion cells to IOP, systemic vascular dysregulation, endothelial dysfunction, and autoimmune imbalances have been suggested as playing a role in the pathophysiology of normal-tension glaucoma. Since inflammation and oxidative stress play a role in all forms of glaucoma, the goal of this review article is to present an overview of the inflammatory and pro-oxidant mechanisms in the pathophysiology of glaucoma and to discuss immunomodulatory and antioxidant treatment approaches.

Oxidative Stress: A Suitable Therapeutic Target for Optic Nerve Diseases?

Optic nerve disorders encompass a wide spectrum of conditions characterized by the loss of retinal ganglion cells (RGCs) and subsequent degeneration of the optic nerve. The etiology of these disorders can vary significantly, but emerging research highlights the crucial role of oxidative stress, an imbalance in the redox status characterized by an excess of reactive oxygen species (ROS), in driving cell death through apoptosis, autophagy, and inflammation. This review provides an overview of ROS-related processes underlying four extensively studied optic nerve diseases: glaucoma, Leber's hereditary optic neuropathy (LHON), anterior ischemic optic neuropathy (AION), and optic neuritis (ON). Furthermore, we present preclinical findings on antioxidants, with the objective of evaluating the potential therapeutic benefits of targeting oxidative stress in the treatment of optic neuropathies.

Valproate reduces retinal ganglion cell apoptosis in rats after optic nerve crush

The retinal ganglion cells of the optic nerve have a limited capacity for self-repair after injury. Valproate is a histone deacetylase inhibitor and multitarget drug, which has been demonstrated to protect retinal neurons. In this study, we established rat models of optic nerve-crush injury and injected valproate into the vitreous cavity immediately after modeling. We evaluated changes in the ultrastructure morphology of the endoplasmic reticulum of retinal ganglion cells over time via transmission electron microscope. Immunohistochemistry and western blot assay revealed that valproate upregulated the expression of the endoplasmic reticulum stress marker glucose-regulated protein 78 and downregulated the expression of transcription factor C/EBP homologous protein, phosphorylated eukaryotic translation initiation factor 2α, and caspase-12 in the endoplasmic reticulum of retinal ganglion cells. These findings suggest that valproate reduces apoptosis of retinal ganglion cells in the rat after optic nerve-crush injury by attenuating phosphorylated eukaryotic translation initiation factor 2α-C/EBP homologous protein signaling and caspase-12 activation during endoplasmic reticulum stress. These findings represent a newly discovered mechanism that regulates how valproate protects neurons.

Glaucoma-related posts from a Chinese social media: An exploratory study.. [DOI: 10.21203/rs.3.rs-2312218/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Purpose: Our study aims to discuss glaucoma patients' needs and Internet habits using big data analysis and Natural Language Processing (NLP) based on deep learning (DL). We also developed and validated DL models to recognize social media data. Methods: In this retrospective study, we used web crawler technology to crawl glaucoma-related topic posts from the glaucoma bar of Baidu Tieba. According to the contents of topic posts, we classified them into posts with or without seeking medical advice. Word Cloud and frequency statistics were used to analyze the contents and visualize the keywords. Two DL models, Bidirectional Long Short-Term Memory (Bi-LSTM) and Bidirectional Encoder Representations from Transformers (BERT), were trained to identify the posts seeking medical advice. The evaluation matrices included: accuracy, F1 value, and the area under the ROC curve (AUC). Results: A total of 10,892 topic posts were included, among them, most were seeking medical advice (N=7071, 64.91%), and seeking advice regarding symptoms or examination (N=4913, 45.11%) dominated the majority, followed by searching for social support , expressing emotions, and sharing knowledge. The word cloud analysis showed that ocular pressure, visual field, examination, and operation were the most frequent words. The accuracy, F1 score, and AUC were 0.891, 0.891, and 0.931 for BERT model, 0.82, 0.821, and 0.890 for Bi-LSTM model. Conclusion: Social media can help enhance the patient-doctor relationship by providing patients’ concerns and cognition about glaucoma. DL models performed well in classifying Chinese medical-related texts, which could play an important role in public health monitoring.

Role of Oxidative Stress in Retinal Disease and the Early Intervention Strategies: A Review

The retina, owing to its cellular anatomy and physical location, is susceptible to generating reactive oxygen species (ROS), which are associated with several major retinal diseases. When ROS exceeds the body's natural antioxidants, the retina is in a state of oxidative stress, which is recognized as the pathogenesis of retinal diseases. The early stage of the pathogenic process is an adaptive change in which oxidative stress and endogenous defense mechanisms occur. If no treatment is applied, the retinal diseases will progress to the pathological stage with neuronal and vascular dysfunction or damage and even blindness. This review summarizes the role of oxidative stress in several common retinal diseases, including retinitis pigmentosa, age-related macular degeneration, diabetic retinopathy, glaucoma, and retinopathy of prematurity. In addition, we discuss the early intervention strategies for these diseases. An outline is provided to identify potential intervention targets for further research. Early intervention for retinal diseases is necessary and urgent and may offer hope to improve patients' quality of life through functional vision.

Beneficial effect of mindfulness based stress reduction on optic disc perfusion in primary open angle glaucoma: A randomized controlled trial

Background and aim

Glaucoma is one of the leading causes of visual impairment worldwide. Next to intraocular pressure (IOP), vascular factors play a major role in glaucoma. Mindfulness-based stress reduction (MBSR) has been shown to reduce the IOP, normalize the stress biomarkers, modulate gene expression, and also improve the quality of life. This study was aimed to assess the effect of MBSR in optic disc perfusion of patients with primary open angle glaucoma (POAG).

Experimental procedure

POAG patients with controlled IOP (<21 mmHg) were randomised in to intervention group (n = 30) and control group (n = 30). Both the groups continued their routine glaucoma medications while the intervention group practiced 45 min of MBSR every day in addition. IOP and optic disc perfusion using OCT-Angiography were recorded at baseline and at 6 weeks for both the groups.

Results

The mean age of the participants were 53.23 ± 8.4yr in intervention and 50.23 ± 7.3yr in the control group (p = 0.06). All the baseline parameters were comparable in both groups. After MBSR, in the intervention group there was a significant reduction of IOP (p=0.001), increase in circum-papillary vessel density in superior quadrant (15.8%-17.4%, p=0.02) and nasal quadrant (14.2%-16.5%, p=0.01), increase in circum papillary vascular perfusion, in superior quadrant (38.9%-41.1%, p<0.001), in temporal quadrant (42.2%-44.5%, p<0.001), in inferior quadrant (40.1%-43.8%, p<0.001), and in nasal quadrant (40.6%-42.8%, p<0.001). There was also a significant increase in Flux Index after 6weeks (0.38-0.40, p<0.001).

Conclusion

MBSR can reduce barotrauma and improve optic disc perfusion in POAG patients and serve as a useful adjunct to the standard medical therapy.

Efficacy of travoprost for the treatment of patients with glaucoma

BACKGROUND

This study will evaluate the efficacy of travoprost for patients with glaucoma systematically.

METHODS

A comprehensive literature search will be carried from following literature sources from inception to the present: Cochrane Library, MEDLINE, EMBASE, Web of Science, Google scholar, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure. We will only consider randomized controlled trials on assessing the efficacy and safety of travoprost for glaucoma for inclusion. We will use Cochrane risk of bias tool for the methodological quality assessment for each qualified study. If it is possible, we will pool the outcome data, and will perform meta-analysis.

RESULTS

This study will systematically evaluate the efficacy and safety of travoprost for glaucoma. Primary outcomes include intraocular pressure (IOP), mean IOP, and mean reduction of IOP. Secondary outcomes consist of diastolic ocular perfusion pressure, central corneal thickness, and quality of life, as measured by 36-Item Short Form Health Survey, and treatment-related adverse events included hyperemia, eye pain, and eye pruritus.

CONCLUSION

The findings of the present study will summarize the updated evidence of travoprost for patients with glaucoma.PROSPERO registration number: PROSPERO CRD42019126956.