Role of vitamin A in the healing process of alkali caused corneal injury of adult male albino rat: Histological and immunohistochemical study

Abstract

Background and Aim: Alkali burn of the cornea is considered as the most dangerous injury to the eye. It causes corneal infection, ulceration, perforation, neovascularization (NV) and opacification. Vitamin A is necessary for the normal growth and differentiation of epithelium; it is expected to promote the mechanical repair of corneal epithelial defects The present study is planned to investigate the effect of vitamin A eyegel on wound healing of the corneal alkali burn in rats. Materials and Methods: A total of thirty male albino rats were used. Rats were divided randomly into four groups: Group I, the control group; included three rats, received distilled water. Each of group II, III, IV included 9 rats: their central corneas of the right eyes were injured by contacting them with filter paper saturated with 0.01 m NaOH for 45 seconds. Group II, the non-treated group, injured and received distilled water. Group III, the antibiotic treated group, received antibiotic eye drops (lincomycin hydrochloride eye drops) 3 times per day for 3 days. Group IV, vitamin A treated group, received the same course of antibiotic and vitamin A eye gel (Hypotear gel 1000 IU/g) three times per day. for 3 days. The eyeball was taken out, rapidly fixed and processed for light microscopic, immunohistochemical and morphometric studies. Specimens were taken after 24, 48 and 72 hr. post-injury for tissue preparation and study of structural changes and immuno-histochemical analysis using Ki67 (detection of cellular proliferation) and transforming growth factor -beta (TGF-β) which is one of the most critical growth factors in establishing the pathologic lesion after corneal alkali burn. Results: Hematoxylin and eosin stained sections showed rapid healing of corneal ulcer in vitamin A treated group, with absence of neo-vasculariztion and inflammatory cellular infiltration. Immunohistochemical results showed that the use of vitamin A enhance cell proliferation (detected with Ki67) and decrease the expression of TGF-β which is one of the most critical growth factors in establishing the pathological lesion after corneal alkali burn. Conclusions: Vitamin A eye gel helped rapid healing of corneal alkali burn. This effect may be due to its anti-inflammatory effect and stimulation of cell proliferation.

Effect of Platelet Rich Plasma on Corneal Alkali Burn Ulcer in Rabbits

“…Degeneration of Descemet's membrane and endothelial cells (Figure .7). In our study, according to (Jassim et al,, 2020;Zheng et al,2019;Abdelwahab et al, 2017;Khaksar et al, 2013;Ye et al,, 2006;Klang et al, 1999), we used sodium hydroxide as alkaline chemical to induce corneal ulcer model in rabbits as the direct contact of NAOH may cause severe irritation to the skin, mucous membranes and eye. However, some authors used alcohol for ulcer induction (Acosta et al, (2014).…”