School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.
Food Funct. 2011 May;2(5):251-8. doi: 10.1039/c1fo10021a. Epub 2011 Apr 21.
The formation and accumulation of advanced glycation endproducts (AGEs) is a key pathophysiological process involved in various diabetic complications such as diabetic retinopathy. In the present study, for the first time, protective effects of three microalgal strains, including their extracts and active compounds, against both endogenous and exogenous AGEs in cell-based models were investigated. Results showed that in cultured human-derived retinal pigment epithelial ARPE-19 cells, the extract of Chlorella zofingiensis and its nutritional ingredient astaxanthin exhibited significant inhibitory effects on the formation of endogenous N(ε)-carboxymethyllysine (CML), a key AGE representative, through the suppression of intracellular oxidative stress. On the other hand, extracts of Chlorella zofingiensis, Chlorella protothecoides and Nitzschia laevis as well as their nutritional ingredients, namely astaxanthin, lutein and eicosapentaenoic acid (EPA), attenuated the deleterious effects induced by exogenous AGEs, such as cell proliferation and mRNA upregulation of vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMP)-2, which are critical steps involved in the pathogenesis of diabetic retinopathy. These results suggested the positive roles of astaxanthin, lutein and EPA in controlling the development of diabetes. These microalgae, therefore, might be regarded as beneficial foods and preventive agent choices for patients with diabetic retinopathy.
糖基化终产物（AGEs）的形成和积累是各种糖尿病并发症（如糖尿病性视网膜病变）的关键病理生理过程。在本研究中，首次研究了三种微藻菌株，包括它们的提取物和活性化合物，对细胞模型中内源性和外源性 AGEs 的保护作用。结果表明，在培养的人源性视网膜色素上皮 ARPE-19 细胞中，球藻和其营养成分虾青素的提取物通过抑制细胞内氧化应激，对关键 AGE 代表物 N（ε）-羧甲基赖氨酸（CML）的形成表现出显著的抑制作用。另一方面，球藻、原甲藻和膝沟藻的提取物及其营养成分，即虾青素、叶黄素和二十碳五烯酸（EPA），减轻了外源性 AGEs 诱导的有害作用，如细胞增殖和血管内皮生长因子（VEGF）和基质金属蛋白酶（MMP）-2 的 mRNA 上调，这些都是糖尿病性视网膜病变发病机制中的关键步骤。这些结果表明虾青素、叶黄素和 EPA 在控制糖尿病发展方面发挥了积极作用。因此，这些微藻可能被视为糖尿病性视网膜病变患者的有益食品和预防剂选择。
