- 學位論文
龍眼花水萃物改善內皮細胞損傷效果之探討
Longan (Dimocarpus longan Lour.) Flower Water Extract Ameliorates Endothelial Cell Dysfunction
摘要
糖尿病病患體內因長期維持高血糖的情況，容易形成較多的高階醣化終產物 (Advanced glycation end products, AGEs)，而 AGEs目前被認為是造成糖尿病併發症如心血管疾病、腎病變的重要原因。據先前研究顯示高糖及AGEs均會增加氧化壓力的生成引起發炎反應，造成內皮細胞功能失調，並且增加單核球對內皮細胞的黏附作用。本實驗以人類臍靜脈內皮細胞 (HUVECs) 為模型，分為兩個部分探討龍眼花水萃物對高糖及高階醣化終產物誘發的內皮細胞損傷的影響。首先，我們利用高糖處理 HUVECs，發現高糖可誘發 HUVECs之單核球黏附作用增加，而此作用乃透過增加細胞黏附分子ICAM-1及VACM-1蛋白的表現量及減少eNOS的磷酸化而造成，加入龍眼花水萃物則可改善此些現象。第二部分以 AGEs誘導 HUVECs 內皮細胞損傷，實驗中發現AGEs 會降低細胞之存活率並增加 ICAM-1 表現量，而加入龍眼花水萃物共同處理後能顯著降低 ICAM-1 表現量增加之效果，但對細胞存活率則無影響。以上結果顯示龍眼花水萃物具有改善高糖及AGEs 引起之內皮細胞損傷之潛力。
並列摘要
High blood glucose level and advanced glycation end products (AGEs) have been regarded as important factors in the pathogenesis of diabetic complications such as cardiovascular disease and nephropathy. High blood glucose and AGEs not only increase generation of ROS which cause inflammation and endothelial dysfunction, but increase monocyte adherent to endothelial cells. In this study, high glucose (HG) and AGEs induced endothelial dysfunction models were used to investigate the improving effect of longan flower water extracts (LFWE) on endothelial dysfunction. In the first part of this study, HUVECs were treated with HG. We found that HG enhanced adhesion of THP-1 monocyte to HUVECs. Moreover, HG also increased the expression of cell adhesion molecule ICAM-1 and VCAM-1 protein expression and decreased the phosphorylation of endothelial cell NO synthases (eNOS). These findings could be ameliorated by LFWE. In the second part, our results show that AGEs decreased cell viability and increased the expression of ICAM-1. LFWE could improve the AGEs induced ICAM-1 expression, but there is no effect on cell death. In conclusion, we suggested LFWE may has potential to improve endothelial dysfunction induced by high glucose and AGEs.