Therapeutic Efficacy of Topically Applied Antioxidant Medicinal Plant Extracts in a Mouse Model of Experimental Dry Eye

Abstract

Purpose. To investigate the therapeutic effects of topical administration of antioxidant medicinal plant extracts in a mouse model of experimental dry eye (EDE). Methods. Eye drops containing balanced salt solution (BSS) or 0.001%, 0.01%, and 0.1% extracts were applied for the treatment of EDE. Tear volume, tear film break-up time (BUT), and corneal fluorescein staining scores were measured 10 days after desiccating stress. In addition, we evaluated the levels of interleukin- (IL-) 1β, tumor necrosis factor- (TNF-) α, IL-6, interferon- (IFN-) γ, and IFN-γ associated chemokines, percentage of CD4+C-X-C chemokine receptor type 3 positive (CXCR3+) T cells, goblet cell density, number of 4-hydroxy-2-nonenal (4-HNE) positive cells, and extracellular reactive oxygen species (ROS) production. Results. Compared to the EDE and BSS control groups, the mice treated with topical application of the 0.1% extract showed significant improvements in all clinical parameters, IL-1β, IL-6, TNF-α, and IFN-γ levels, percentage of CD4+CXCR3+ T cells, goblet cell density, number of 4-HNE-positive cells, and extracellular ROS production (P < 0.05). Conclusions. Topical application of 0.1% medicinal plant extracts improved clinical signs, decreased inflammation, and ameliorated oxidative stress marker and ROS production on the ocular surface of the EDE model mice.

Anti-Inflammatory and Antioxidative Effects of Camellia japonica on Human Corneal Epithelial Cells and Experimental Dry Eye: In Vivo and In Vitro Study

“…59,60 In vitro studies further revealed that lipid and mitochondrial oxidative damage causes inflammation in HCE cells. 39,61 As mentioned above, various anti-inflammatory drugs, such as topical steroids and cyclosporine, have been widely used to treat DED, and studies have shown that anti-inflammatory treatment has a beneficial effect on tear secretion, tear film stability, and ocular surface integrity. 62,63 In addition, as oxidative stress has a potent role in the pathogenesis of DED, antioxidative treatment has shown therapeutic effects against DED, proven by the improvement in various ocular surface parameters.…”

“…62,63 In addition, as oxidative stress has a potent role in the pathogenesis of DED, antioxidative treatment has shown therapeutic effects against DED, proven by the improvement in various ocular surface parameters. 61 Therefore, we further investigated the effects of CJ extract on various clinical parameters, including tear volume, tear film BUT, and corneal fluorescein staining in a mouse model of EDE. Despite continuous exposure to desiccant stress and rigorous anticholinergic treatment, 0.01% and 0.1% CJ extract-treated eyes showed an improved tear film BUT and increased tear production.…”

Herbal Extracts That Reduce Ocular Oxidative Stress May Enhance Attentive Performance in Humans

“…purpurea Makino , and Cassia tora L. increased the antioxidant enzymes heme oxygenase-1 (HO-1), peroxiredoxin-1 (Prx-1), catalase (CAT), and superoxide dismutase-2 (SOD-2) in corneal epithelial cells that protect against oxidative stress induced by blue light [5–7]. Further, previous human and animal studies [6, 7] have shown that herbal extracts are an effective treatment for symptoms of dry-eye disease. Thus, the herbal extracts reduced eye blinks during the ANT experiment by reducing oxidative stress on corneal epithelial cells.…”

“…japonica Kitagawa , Angelica dahurica Bentham et Hooker, Rehmannia glutinosa Liboschitz var. purpurea Makino , and Cassia tora L., which have antioxidant and anti-inflammatory effects that protect human corneal epithelial cells from oxidative stress [5–7]. The pad was made of polypropylene and viscos rayon.…”

“…Recently, Choi et al [6, 7] also showed that herbal extracts can reduce the symptoms of dry-eye disease (DED).…”