Herbal molecules in eye diseases

Lebanese Medicinal Plants with Ophthalmic Properties

Lebanon benefits from a rich biodiversity, with medicinal and aromatic plants (MAPs) representing an important part of the country's natural wealth; however, limited data are available documenting medicinal plants being employed in eye health. This review is the first to document Lebanese medicinal plants with ophthalmic characteristics and phytochemistry that might be beneficial in the development of new, accessible, and efficient ocular medications. In this study, we searched for studies on ocular therapeutic plants using known resources, including PubMed, ScienceDirect, and Google Scholar, and confirmed these plants' presence within the Lebanese flora. The efficacy of 52 species from 28 families, including two endemic species (Crepis libanotica and Salvia libanotica), has been documented. Their Latin names, regional names, ocular medical applications, the plant parts used, and preparation forms are detailed below. The largest number of species belongs to the Lamiaceae family (21%), followed by Asteraceae (14%) and Solanaceae (7%). The most commonly used plant parts are the stems, leaves, and seeds. Ocular treatments fall into several categories: inflammation, infection, irritation, dry-eye, eyewash, the prevention or delay of cataracts, and general eye problems. A significant percentage (68%) of the medicinal plants target the anterior part of the eye. Some of the reported plants can be harmful to the eyes and should be handled with caution. The Lebanese medicinal plants listed, constituting a local heritage with global importance, could be used for treating ophthalmic ailments and require special screening and preservation.

Diabetic Retinopathy - Pathophysiology to Treatment: A Review

Diabetic retinopathy (DR) is a microvascular disease affecting the eyes of diabetic patients, and is the most prevalent complication of diabetes mellitus. Vision improvement is not possible in the majority of DR patients. Several studies have indicated that microvascular changes, inflammation, oxidative stress, and retinal neurodegeneration are involved in the pathogenesis of DR. Therefore, there is an urgent need for the development of new and effective treatment for DR. Understanding the molecular mechanisms involved in the pathogenesis of disease will pave a way for better treatment and management of DR. This article has emphasized the molecular pathogenesis and treatment of DR.

Applications of Nanotechnology-mediated Herbal Nanosystems for Ophthalmic Drug

In recent years, herbal nanomedicines have gained tremendous popularity for novel drug discovery. Nanotechnology has provided several advances in the healthcare sector, emerging several novel nanocarriers that potentiate the bioavailability and therapeutic efficacy of the herbal drug. The recent advances in nanotechnology with accelerated strategies of ophthalmic nanosystems have paved a new path for overcoming the limitations associated with ocular drug delivery systems, such as low bioavailability, poor absorption, stability, and precorneal drug loss. Ophthalmic drug delivery is challenging due to anatomical and physiological barriers. Due to the presence of these barriers, the herbal drug entry into the eyes can be affected when administered by following multiple routes, i.e., topical, injectables, or systemic. However, the advancement of nanotechnology with intelligent systems enables the herbal active constituent to successfully entrap within the system, which is usually difficult to reach employing conventional herbal formulations. Herbal-loaded nanocarrier drug delivery systems demonstrated enhanced herbal drug permeation and prolonged herbal drug delivery. In this current manuscript, an extensive search is conducted for original research papers using databases Viz., PubMed, Google Scholar, Science Direct, Web of Science, etc. Further painstaking efforts are made to compile and update the novel herbal nanocarriers such as liposomes, polymeric nanoparticles, solid lipid nanoparticles, nanostructure lipid carriers, micelles, niosomes, nanoemulsions, dendrimers, etc., which are mostly used for ophthalmic drug delivery system. This article presents a comprehensive survey of diverse applications used for the preventative measures and treatment therapy of varied eye disorders. Further, this article highlights the recent findings that the innovators are exclusively working on ophthalmic nanosystems for herbal drug delivery systems. The nanocarriers are promising drug delivery systems that enable an effective and supreme therapeutic potential circumventing the limitations associated with conventional ocular drug delivery systems. The nanotechnology-based approach is useful to encapsulate the herbal bioactive and prevent them from degradation and therefore providing them for controlled and sustained release with enhanced herbal drug permeation. Extensive research is still being carried out in the field of herbal nanotechnology to design an ophthalmic nanosystem with improved biopharmaceutical properties.

The potential health benefits of dietary natural plant products in age related eye diseases

In the past decade, there has been a tremendous increase in the number of cases of age-related eye diseases such as age-related macular degeneration (AMD), cataract, diabetic retinopathy and glaucoma. These diseases are the leading causes of visual impairment and blindness all over the world and are associated with many pathological risk factors such as aging, pollution, high levels of glucose (hyperglycaemia), high metabolic rates, and light exposure. These risk factors lead to the generation of uncontrollable reactive oxygen species (ROS), which causes oxidative stress. Oxidative stress plays a crucial role in the pathogenesis of age-related eye diseases through the activation of nuclear factor kappa B (NF-κB), vascular endothelial growth factor (VEGF), and lipid peroxidation, which leads to the production of inflammatory cytokines, angiogenesis, protein and DNA damages, apoptosis that causes macular degeneration (AMD), cataract, diabetic retinopathy and glaucoma. This review provides updated information on the beneficial effects of dietary natural plant products (DPNPs) against age-related eye diseases. In this review, supplementation of DPNPs demonstrated preventive and therapeutic effects on people at risk of or with age-related eye diseases due to their capacity to scavenge free radicals, ameliorate inflammatory molecules, neutralize the oxidation reaction that occurs in photoreceptor cells, decrease vascular endothelial growth factor and the blood-retinal barrier and increase the antioxidant defence system. However, further experiments and clinical trials are required to establish the daily doses of DPNPs that will safely and effectively prevent age-related eye diseases.