The Effect of Ascorbic acid on Endotoxin-induced Fibrosis

Lee, Sung Chul; Kwon, Oh Woong

Abstract

Ascorbic acid, which is toxic to retinal pigment epithelial cells in vitro, can stimulate fibrotic tissue formation. This study investigated the influence of ascorbic acid on endotoxin-induced fibrosis. Experimental vitreal fibrosis was induced in the rabbit by injecting endotoxin with or without ascorbic acid into the vitreous, and compared the degree of fibrosis. Inflammation induced by 1 microgram of endotoxin first appeared on day 1, remained on day 3. On day 7, organized membrane was developed. The striking decrease in ascorbic acid occurred after the intravitreal injection of endotoxin. In a series of experiment in which ascorbic acid were used, endotoxin produced less inflammatory response compared to the control. Rabbits which were injected 1 microgram of endotoxin (with or without ascorbic acid) had shown significant vitreal fibrosis. Even though the high conentration of ascorbic acid can provide extacellular protection for the ocular tissues during ocular inflammation, It was not effective in preventing the formation of membrane.