Inhibition of Ultraviolet B-Induced Expression of the Proinflammatory Cytokines TNF-α and VEGF in the Cornea by Fucoxanthin Treatment in a Rat Model

Abstract

Ultraviolet B (UVB) irradiation is the most common cause of radiation damage to the eyeball and is a risk factor for human corneal damage. We determined the protective effect of fucoxanthin, which is a carotenoid found in common edible seaweed, on ocular tissues against oxidative UVB-induced corneal injury. The experimental rats were intravenously injected with fucoxanthin at doses of 0.5, 5 mg/kg body weight/day or with a vehicle before UVB irradiation. Lissamine green for corneal surface staining showed that UVB irradiation caused serious damage on the corneal surface, including severe epithelial exfoliation and deteriorated epithelial smoothness. Histopathological lesion examination revealed that levels of proinflammatory cytokines, including tumor necrosis factor-α (TNF-α) and vascular endothelial growth factor (VEGF), significantly increased. However, pretreatment with fucoxanthin inhibited UVB radiation-induced corneal disorders including evident preservation of corneal surface smoothness, downregulation of proinflammatory cytokine expression, and decrease of infiltrated polymorphonuclear leukocytes from UVB-induced damage. Moreover, significant preservation of the epithelial integrity and inhibition of stromal swelling were also observed after UVB irradiation in fucoxanthin-treated groups. Pretreatment with fucoxanthin may protect against UVB radiation-induced corneal disorders by inhibiting expression of proinflammatory factors, TNF-α, and VEGF and by blocking polymorphonuclear leukocyte infiltration.

A Murine Model of Acute Allergic Conjunctivitis Induced by Continuous Exposure to Particulate Matter 2.5

“…On day 19, the mice were anesthetized with 2.5% Avertin (Sigma-Aldrich, St. Louis, MO, USA) at 400 mg/kg by intraperitoneal injection for tear ferning tests and ocular surface photography. The photographs were assessed later for ocular surface indexes, including smoothness, 28 opacity, 29 topography, and lissamine green stain 30 following the criteria used in previous publications. The mice were then killed to collect eyes with their periocular tissues for further analyses.…”

Fucoxanthin Alleviates Oxidative Stress through Akt/Sirt1/FoxO3α Signaling to Inhibit HG-Induced Renal Fibrosis in GMCs

“…Although relatively fewer studies of Fx on DN, several studies have reported bioactivities of Fx about inflammation inhibition and antioxidant properties, indicating its potential anti-diabetic role. In rat models, pretreatment with Fx inhibited UV-B radiation induced corneal disorders including evident preservation of corneal surface smoothness, downregulation of proinflammatory cytokine expression, and decrease of infiltrated polymorphonuclear leukocytes from UV-B induced damage [31]. The combination of Fx and rosmarinic acid improved antioxidant and anti-inflammatory profiles through the down-regulation of inflammasome components, such as NLRP3 and ASC, and increased Nrf2 and HO-1 antioxidant genes expression in HaCaT Keratinocytes [32].…”

Inhibition of microRNA‐129‐5p expression ameliorates ultraviolet ray‐induced corneal epithelial cell injury via upregulation of EGFR

“…After fixing the head, the left eye was covered. In a room devoid of light, the right eye of each mouse was exposed to wavelength of 310 nm using an ultraviolet lamp, and the intensity was 550 µW/cm 2 , lasting for 3 min for five consecutive days (Chen et al, ). After 36 hr of induction, the model was examined under a slit lamp and scored according to Dicky's grading criteria for edematous corneal turbid (Dickey, Cassidy, & Bouchard, ; the same below) and the model induction was judged for successful establishment.…”