Therapeutic Effect of Melatonin in Experimental Uveitis

Abstract

Uveitis is a common ophthalmic disorder that can be induced in hamsters by a single intravitreal injection of bacterial lipopolysaccharide (LPS). To examine the therapeutic effects of melatonin on uveitis, a pellet of melatonin was implanted subcutaneously 2 hours before the intravitreal injection of either vehicle or LPS. Both 24 hours and 8 days after the injection, inflammatory responses were evaluated in terms of i) the integrity of the blood-ocular barrier, ii) clinical signs, iii) histopathological studies, and iv) retinal function. Melatonin reduced the leakage of proteins and cells in the anterior segment of LPS-injected eyes, decreased clinical signs such as dilation of the iris and conjunctival vessels, and flare in the anterior chamber, and protected the ultrastructure of the blood-ocular barrier. A remarkable disorganization of rod outer segment membranous disks was observed in animals injected with LPS, whereas no morphological changes in photoreceptor outer segments were observed in animals treated with melatonin. Furthermore, melatonin prevented a decrease in LPS-induced electroretinographic activity. In addition, melatonin significantly abrogated the LPS-induced increase in retinal nitric-oxide synthase activity, tumor necrosis factor-␣, and nuclear factor B p50 and p65 subunit levels. These results indicate that melatonin prevents the clinical, biochemical, histological, ultrastructural, and functional consequences of experimental uveitis, likely through a nuclear factor B-dependent mechanism, and support the use of melatonin as a new therapeutic strategy for the treatment of uveitis. (Am J Pathol

Therapeutic benefit of melatonin in refractory central serous chorioretinopathy

“…16 Moreover, we showed that melatonin significantly attenuates biochemical, clinical, histological, ultrastructural, and functional alterations induced by experimental uveitis, and it preserves the BRB integrity. 49 As already mentioned, glucocorticoids induce and aggravate CSCR. The antagonism exerted by melatonin on the glucocorticoid response has been well established.…”

“…Five patients with chronic CSCR served as a control group. The mean age of control patients was 44 years old (range, [34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53], with the woman/man ratio being 1 : 4. The number of right and left eyes studied was also similar (3 right eyes and 2 left eyes).…”

Anti-inflammatory and ultrastructural effects of Turkish propolis in a rat model of endotoxin-induced uveitis

“…These effects were less marked in the group treated with both LPS and propolis. This indicated that propolis may stimulate www.fhc.viamedica.pl repair of the outer nuclear layer of the neural retina; this hypothesis will be tested in a future study of propolis in chronic uveitis [29].…”

Mammalian Telomeric DNA Suppresses Endotoxin-induced Uveitis

“…Uveitis is an ophthalmic disorder that causes vision loss in developed countries (22,23) and is characterized by acute, recurrent, or persistent ocular inflammation, the breakdown of the blood-ocular barrier, and infiltration of leukocytes (24). The underlying causes of uveitis can vary.…”