Antioxidant Effects of Spinach (Spinacia oleracea L.) Supplementation in Hyperlipidemic Rats.
Increased consumption of fresh vegetables that are high in polyphenols has been associated with a reduced risk of oxidative stress-induced disease. The present study aimed to evaluate the antioxidant effects of spinach in vitro and in vivo in hyperlipidemic rats. For measurement of in vitro antioxidant activity, spinach was subjected to hot water extraction (WE) or ethanol extraction (EE) and examined for total polyphenol content (TPC), oxygen radical absorbance capacity (ORAC), cellular antioxidant activity (CAA), and antigenotoxic activity. The in vivo antioxidant activity of spinach was assessed using blood and liver lipid profiles and antioxidant status in rats fed a high fat-cholesterol diet (HFCD) for 6 weeks. The TPC of WE and EE were shown as 1.5±0.0 and 0.5±0.0 mg GAE/g, respectively. Increasing the concentration of the extracts resulted in increased ORAC value, CAA, and antigenotoxic activity for all extracts tested. HFCD-fed rats displayed hyperlipidemia and increased oxidative stress, as indicated by a significant rise in blood and liver lipid profiles, an increase in plasma conjugated diene concentration, an increase in liver thiobarbituric acid reactive substances (TBARS) level, and a significant decrease in manganese superoxide dismutase (Mn-SOD) activity compared with rats fed normal diet. However, administration of 5% spinach showed a beneficial effect in HFCD rats, as indicated by decreased liver TBARS level and DNA damage in leukocyte and increased plasma conjugated dienes and Mn-SOD activity. Thus, the antioxidant activity of spinach may be an effective way to ameliorate high fat and cholesterol diet-induced oxidative stress.
Department of Food and Nutrition, Sunchon National University, Jeonnam 540-950, Korea.
Sang-Heui
SH
Ko
Department of Food and Nutritional Science, Kyungnam University, Gyeongnam 631-701, Korea.
Jae-Hee
JH
Park
Department of Food and Nutritional Science, Kyungnam University, Gyeongnam 631-701, Korea.
So-Yun
SY
Kim
Department of Food and Nutritional Science, Kyungnam University, Gyeongnam 631-701, Korea.
Seon Woo
SW
Lee
Department of Food and Nutrition, Sunchon National University, Jeonnam 540-950, Korea.
Soon-Sil
SS
Chun
Department of Food and Nutritional Science, Kyungnam University, Gyeongnam 631-701, Korea.
Eunju
E
Park
comet assay; hyperlipidemic rat; liver TBARS; spinach; tail DNA