Chan, HHL

Fu, ZJ

Fung, FKC

Li, SY

Lo, ACY

Wong, D

Investigative Ophthalmology & Visual Science

PURPOSE: Lutein protects retinal neurons by its anti-oxidative and anti-apoptotic properties in ischemia/reperfusion (I/R) injury while its anti-inflammatory effects remain unknown. As Müller cells play a critical role in retinal inflammation, the effect of lutein on Müller cells was investigated in a murine model of I/R injury and a culture model of hypoxic damage. METHODS: Unilateral retinal I/R was induced by a blockade of internal carotid artery using the intraluminal method in mice. Ischemia was maintained for 2 hours followed by 22 hours of reperfusion, during which either lutein (0.2 mg/kg) or vehicle was administered. Flash electroretinogram (flash ERG) and glial fibrillary acidic protein (GFAP) activation were assessed. Lutein's effect on Müller cells was further evaluated in immortalized rat Müller cells (rMC-1) challenged with cobalt chloride-induced hypoxia. Levels of IL-1β, cyclooxygenase-2 (Cox-2), TNFoα and nuclear factor-NF-kappa-B (NF-κB) were examined by Western blot analysis. RESULTS: Lutein treatment minimized deterioration of b-wave/a-wave ratio and oscillatory potentials as well as inhibited upregulation of GFAP in retinal I/R injury. In cultured Müller cells, lutein treatment increased cell viability and reduced level of nuclear NF-κB, IL-1β, and Cox-2, but not TNFα after hypoxic injury. CONCLUSIONS: Reduced gliosis in I/R retina was observed with lutein treatment, which may contribute to preserved retinal function. Less production of pro-inflammatory factors from Müller cells suggested an anti-inflammatory role of lutein in retinal ischemic/hypoxic injury. Together with our previous studies, our results suggest that lutein protected the retina from ischemic/hypoxic damage by its anti-oxidative, antiapoptotic, and anti-inflammatory properties.link_to_OA_fulltex

HKU Scholars Hub

Anti-inflammatory effects of lutein in retinal ischemic/ hypoxic injury: In vivo and in vitro studies

PURPOSE. Lutein protects retinal neurons by its anti-oxidative and anti-apoptotic properties in ischemia/reperfusion (I/R) injury while its anti-inflammatory effects remain unknown. As Muller cells play a critical role in retinal inflammation, the effect of lutein on Muller cells was investigated in a murine model of I/R injury and a culture model of hypoxic damage. METHODS. Unilateral retinal I/R was induced by a blockade of internal carotid artery using the intraluminal method in mice. Ischemia was maintained for 2 hours followed by 22 hours of reperfusion, during which either lutein (0.2 mg/kg) or vehicle was administered. Flash electroretinogram (flash ERG) and glial fibrillary acidic protein (GFAP) activation were assessed. Lutein's effect on Muller cells was further evaluated in immortalized rat Muller cells (rMC-1) challenged with cobalt chloride-induced hypoxia. Levels of IL-1 beta, cyclooxygenase-2 (Cox-2), TNF alpha, and nuclear factor-NF-kappa-B (NF-kappa B) were examined by Western blot analysis. RESULTS. Lutein treatment minimized deterioration of b-wave/a-wave ratio and oscillatory potentials as well as inhibited up-regulation of GFAP in retinal I/R injury. In cultured Muller cells, lutein treatment increased cell viability and reduced level of nuclear NF-kappa B, IL-1 beta, and Cox-2, but not TNF alpha after hypoxic injury. CONCLUSIONS. Reduced gliosis in I/R retina was observed with lutein treatment, which may contribute to preserved retinal function. Less production of pro-inflammatory factors from Muller cells suggested an anti-inflammatory role of lutein in retinal ischemic/hypoxic injury. Together with our previous studies, our results suggest that lutein protected the retina from ischemic/hypoxic damage by its anti-oxidative, antiapoptotic, and anti-inflammatory properties.School of Optometr

The Hong Kong Polytechnic University Pao Yue-kong Library

Anti-inflammatory effects of lutein in retinal ischemic/hypoxic injury : in vivo and in vitro studies

Chan, HH

Title Anti-inflammatory effects of lutein in retinal ischemic injury: invivo and in vitro studiesAuthor(s) Li, SY; Fung, FKC; Chan, HH; Wong, D; Lo, ACYCitationThe 20th Biennial Meeting of the International Society for EyeResearch (ISER 2012), Berlin, Germany, 21-25 July 2012,abstract no. P173Issued Date 2012URL http://hdl.handle.net/10722/166823Rights Creative Commons: Attribution 3.0 Hong Kong LicenseP173 ANTI-INFLAMMATORY EFFECTS OF LUTEIN IN RETINAL ISCHEMIC INJURY: IN VIVO AND IN VITRO STUDIES S.-Y. Li1, F.K. Fung1, H.H. Chan2, D. Wong1,3, A.C. Lo1,3 1Eye Institute, The University of Hong Kong, 2School of Optometry, The Hong Kong Polytechnic University, 3Research Center of Heart, Brain, Hormone and Healthy Aging, The University of Hong Kong, Hong Kong, Hong Kong S.A.R. Purpose: Lutein has been shown to protect retinal neurons from damage during retinal ischemia/reperfusion (I/R), possibly through both anti-oxidative and anti-apoptotic properties. As inflammation plays a critical role in I/R injury, the anti-inflammatory effect of lutein was investigated in the present study.  Methods: Unilateral retinal I/R was induced by the blockade of internal carotid artery using intraluminal method in C57Bl/6N mice. Ischemia was maintained for 2 hours followed by 22 hours of reperfusion during which either lutein or vehicle was administered. Electroretinography (ERG) and GFAP activation were examined. An in vitro model of induced hypoxia was also used to elucidate the effects of lutein on Muller cells. Western blotting of IL-1β, Cox-2, TNFα, and NFκB were performed.  Results: Lutein treatment minimized the deterioration in ERG response and activation of GFAP in the animal model of retinal I/R injury. Decreased levels of IL-1β and Cox-2, but not TNFα, were observed in the cell culture model of hypoxia. In addition, the level of nuclear fraction of NFκB was also decreased in the lutein treatment group.  Conclusions: Retinal function was preserved with lutein treatment. Reduced production of inflammatory factors from Muller cells was noted, suggesting an anti-inflammatory role of lutein. Together with our previous study, these results suggest that lutein protects the retina from ischemic/hypoxic damage by its anti-oxidative, anti-apoptotic and anti-inflammatory properties.  COI/Financial disclosure: This research was supported by the grants from the Hong Kong Research Grants Council (GRF #HKU773210M) and the University Development Fund from The University of Hong Kong.   