Anti-inflammatory effect of lycopene on endotoxin-induced uveitis in rats / Efeito anti-inflamatório do licopeno na uveíte induzida por endotoxina em ratos

ABSTRACT Purpose: We evaluated the efficacy of lycopene, a dietary carotenoid and potent antioxidant, against ocular inflammation and oxidative stress in an experimental uveitis model. Methods: Endotoxin-induced uveitis (EIU) was induced in Sprague-Dawley rats by a single subcutaneous injection of 200 μg lipopolysaccharide (LPS). Induction of EIU was preceded by daily intraperitoneal injection of 10 mg/kg lycopene for three consecutive days (Lycopene + LPS group) or equivolume vehicle (Vehicle + LPS group). A positive control group received 1 mg/kg dexamethasone pretreatment (DEX + LPS), and a negative control group received daily vehicle injection but no LPS (Vehicle Control). Twenty-four hours after LPS or final vehicle administration, eyes were enucleated, and aqueous humor was collected for measurement of the number of infiltrating cells, total protein concentration, and levels of nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and oxidative stress markers. Inflammatory response severity was compared among groups clinically and histopathologically. Results: Infiltrating cell number, total protein concentration, and NO, TNF-α, and IL-6 levels were significantly elevated in the aqueous humor of Vehicle + LPS group rats compared to Vehicle Controls. Compared to the Vehicle + LPS group, lycopene pretreatment significantly reduced aqueous humor concentrations of oxidative stress markers, NO (0.29 ± 0.1 μM vs. 0.19 ± 0.1 μM, p=0.003), TNF-α (71.0 ± 22.3 ng/ml vs. 50.1 ± 2.1 ng/ml, p=0.043), and IL-6 (121.6 ± 3.0 pg/ml vs. 111.1 ± 5.6 pg/ml, p=0.008). Inflammatory score was also reduced (2.0 ± 0.0 vs. 0.4 ± 0.5, p=0.001). Lycopene reduced the infiltrating cell count and protein concentration, but differences did not reach significance. Most lycopene effects were equivalent to dexamethasone. Conclusions: Lycopene may aid in the clinical management of uveitis by suppressing inflammation and oxidative stress.

RESUMO Objetivo: Avaliamos o efeito do licopeno, um carotenóide dietético e um potente anti-oxidante, sobre a inflamação ocular e estresse oxidativo em modelo de uveíte experimental. Métodos: Uveíte foi induzida por endotoxina (EIU) em ratos Sprague-Dawley por uma única injeção subcutânea de 200 ug de lipopolissacárido (LPS). A indução de EIU foi precedida por injeção intraperitoneal de licopeno em uma dose de 10 mg/kg (grupo LPS + Licopeno) ou veículo de mesmo volume (grupo LPS + Veículo), durante 3 dias consecutivos. O grupo controle positivo recebeu uma dose de 1 mg/kg de Dexametasona (grupo DEX + LPS) e o grupo controle negativo recebeu doses diárias de veículo mas sem LPS (grupo Controle Veículo). Vinte e quatro horas após a administração do LPS, os olhos foram enucleados, humor aquoso foi recolhido, e o número de células infiltrativas, a concentração de proteína, assim como os níveis de óxido nítrico (NO), fator de necrose tumoral α (TNF-α), interleucina-6 e marcadores de estresse oxidativo foram determinados no humor aquoso. Além disso, a resposta inflamatória foi avaliada clinicamente e histologicamente. Resultados: As células infiltrativas, concentração de proteína, o NO, TNF-α, interleucina-6 foram significativamente elevados no humor aquoso de ratos do grupo Grupo LPS + Veículo quando comparados ao Grupo Controle Veículo. O tratamento com licopeno diminuiu significativamente estes aumentos. Comparado ao Grupo LPS + Veículo, o licopeno reduziu significativamente as concentrações no humor aquoso dos marcadores de estresse oxidativo e NO (de 0,29 ± 0,1 μM para 0,19 ± 0,1 μM, p=0,003), o TNF-α (de 71,0 ± 22,3 ng/ml para 50,1 ± 2,1 ng/ml, p=0,043), interleucina-6 (de 121,6 ± 3,0 pg/ml para 111,1 ± 5,6 pg/ml, p=0,008). Do mesmo modo, o aumento do número de células infiltrativas no tecido uveal em seções histológicas foi significativamente inibido pelo licopeno, a pontuação inflamatória diminuiu de 2,0 ± 0,0 para 0,4 ± 0,5, p=0,001. Embora, não tenha sido estatisticamente significativo, o licopeno reduziu a contagem de células infiltrativas e a concentração de proteínas no humor aquoso. Conclusões: Estes resultados sugerem que o licopeno pode ter efeitos benéficos no tratamento da inflamação ocular, através dos seus efeitos anti-inflamatórios e antioxidantes.

The effect of anterior transposition of the inferior oblique muscle on eyelid configuration and function.

Purpose: To evaluate the alteration of lower lid configuration and function with anterior transposition surgery of the inferior oblique (IO) muscle. Patients and Methods: A prospective clinical trial was conducted on a consecutive series of patients underwent anterior transposition of the IO as a sole operation. All patients received a thorough ophthalmic examination 1 day before and 3 months after surgery. Output parameters were consisted of palpebral fissure, margin reflex distance 1–2, lower lid function, hertel value, and lower lid crease. The differences of the collected data were calculated for statistical significance by using the Wilcoxon test. Results: A total of 19 eyes of 16 consecutive patients were included. The median preoperative grade of IO overaction was 3.5 (ranging from 3 to 4), which decreased to 0 (ranging from 0 to 2) postoperatively (P < 0.05). No significant change was observed in all parameters 3 months postoperatively (P > 0.05). Conclusion: In this study, no significant effect on lower lid configuration and function was observed following IO anterior transposition in which the disinserted muscle was placed posterior to inferior rectus insertion.