혈당강하 효과가 있다고 알려진 해당근 추출물을 이용하여 AGEs 생성 저해에 따른 초기 동맥경화증에 대한 효과에 대하여 검토하였다. 먼저 해당근 추출물이 AGEs에 의하여 생성이 촉진된 ROS를 제거하는 효과가 있는지를 확인하기 위하여 항산화 활성을 측정하였다. 총 플라보노이드 함량을 측정한 결과 해당근의 메탄올 추출물은 $128.1{pm}2.0;{mu}g$ quercetin equivalents(QE)/mg DM,총 폴리페놀 함량은 $345.2{pm}5.7;{mu}g$ gallic acid equivalents(GAE)/mg DM으로 나타났다. 환원력 측정을 위한 FRAP assay는 $2.19{pm}0.1;mM$ $FeSO_4{cdot}7H_2O$/mg DM으로 $25.5{pm}0.3$ $FeSO_4{cdot}7H_2O$/mg DM 인 ascorbic acid에 비해 약 9% 정도의 환원력을 가지고 있었으며, 전자공여능의 경우 $DPPHSC_{50}$값이 $34.2{pm}0.1;{mu}g$ DM/mL로 대조군인 ascorbic acid의 $6.8{pm}0.1;{mu}g$ DM/mL과 비교하여 약 20% 정도의 높은 항산화력을 갖고 있었다. 또한, HPLC 분석을 통해 해당근 생물 100 g을 기준으로 240 mg의 EGCG와 50 mg의 kaempferol을 함유하는 것으로 나타났다. AGEs에 의해 유도된 HUVEC의 ROS 생성 저해 효과는 해당근 추출물 100, $500;{mu}g/mL$ 처리 시 각각 63, 77%로 나타났다. 또한, monocyte adherent assay에서 해당근 추출물은 $100;{mu}g/mL$ 처리시 정상을 0%로 하였을 때 AGEs에 의해 유도된 단핵구 부착을 33%, $500;{mu}g/mL$ 처리시 약 75% 정도로 농도 의존적으로 부착을 저해하는 것을 관찰할 수 있었으며, 유도되지 않은 HUVEC의 저항은 $113{Omega}{cdot}cm^2$ 에서 glycer-AGEs 처리 시 $88{Omega}{cdot}cm^2$로 낮아진 것을 해당근 추출물을 $100;{mu}g/mL$ 처리 시 약 $102{Omega}{cdot}cm^2$, $500;{mu}g/mL$ 처리시 약 $106{Omega}{cdot}cm^2$로 저항의 감소를 억제하는 것을 관찰할 수 있었다.
Rosa rugosa has traditionally been used as a folk remedy for diabetes. The objective of this study was therefore to demonstrate the inhibition of endothelial dysfunction activities through antioxidants and the anti-glycation of Rosa rugosa roots. Dried roots of Rosa rugosa were boiled in methanol for three hours, evaporated and lyophilized with a freeze-dryer. The methanolic extract of Rosa rugosa roots (RRE) was tested for antioxidant activities by measuring total polyphenol (TP) content, flavonoid content, 1,1-diphenyl-2-picrylhydrazyl free radical-scavenging activity (DPPH) assay, and ferric-reducing antioxidant power (FRAP) assay. The total TP content, flavonoid content, FRAP value, and $DPPHSC_{50}$ are $345.2;{mu}g$ gallic acid equivalents/mg dry matter (DM), $128.1;{mu}g$ quercetin equivalents/mg DM, 2.2 mM $FeSO_4$/mg DM and $34.2;{mu}g$ DM/mL, respectively. Treatment of RRE significantly lowered fluorescent formation due to advanced glycation reaction. In addition, reactive oxygen species (ROS) scavenging assay, monocyte adherent assay and transendothelial electrical resistance (TEER) assay were performed to investigate the possibility that RRE improves endothelial dysfunction-induced diabetic complications. The adhesion of THP-1 to treated HUVEC with RRE ($100;{mu}g/mL$; 33% and $500;{mu}g/mL$; 75%) was significantly reduced compared to HUVEC stimulated by glyceraldehydes-AGEs (advanced glycation end product). The TEER value ($88;{Omega}{cdot}cm^2$) of stimulated HUVEC by glyceraldehydes-AGEs was reduced compared to non-stimulation ($113;{Omega}{cdot}cm^2$). However, normalization with RRE increased endothelial permeability in a dose-dependent manner ($100;{mu}g/mL$; $102;{Omega}{cdot}cm^2$ and $500;{mu}g/mL$; $106;{Omega}{cdot}cm^2$). Thus, these results suggest that Rosa rugosa roots could be a novel candidate for the prevention of diabetic complications through antioxidants and inhibition of advanced glycation end product formation.
