![]() |
|
|
Department of Bioresource Engineering, Faculty of Agriculture, Yamagata University, Yamagata, Japan and Course of the Science of * Bioresources, The United Graduate School of Agricultural Sciences, Iwate University, Iwate, Japan
2To whom correspondence should be addressed. E-mail: takenaka{at}tds1.tr.yamagata-u.ac.jp.
The effect of soy protein, soy isoflavones and saponins on paraquat (PQ)-induced oxidative stress was investigated in rats. Rats were fed experimental diets containing casein (CAS), soy protein (SPI), and casein with soy isoflavones and saponins (CAS + IS). The diets were supplemented or not with 0.025% paraquat (CAS + PQ, SPI + PQ, and CAS + IS + PQ). The protective effects of soy protein, soy isoflavones, and saponins on paraquat-induced oxidative stress were examined. Ingestion of soy protein generally mitigated the lung enlargement (P = 0.076), loss of body weight (P = 0.051) and oxidation of liver lipid (P = 0.043) and glutathione (P = 0.035) induced by paraquat, although soy isoflavones and saponins did not. To determine whether soy protein exerted its antioxidative effects by preventing paraquat absorption from digestive organs, rats were fed CAS or SPI diets and orally administered a 12.5 g/L paraquat solution. Plasma, urine, and fecal paraquat concentrations did not differ between the two groups, indicating that soy protein did not prevent paraquat absorption. The present study suggests that intake of soy protein itself, but not soy isoflavones and saponins, reduces paraquat-induced oxidative stress in rats, although this effect was not due to reduced absorption of paraquat from digestive organs.
KEY WORDS: rats soy protein paraquat oxidative stress isoflavone saponin
This article has been cited by other articles:
![]() |
H. E. C. Hanwell, C. D. Kay, J. W. Lampe, B. J. Holub, and A. M. Duncan Acute Fish Oil and Soy Isoflavone Supplementation Increase Postprandial Serum (n-3) Polyunsaturated Fatty Acids and Isoflavones but Do Not Affect Triacylglycerols or Biomarkers of Oxidative Stress in Overweight and Obese Hypertriglyceridemic Men J. Nutr., June 1, 2009; 139(6): 1128 - 1134. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Vega-Lopez, K.-J. Yeum, J. L Lecker, L. M Ausman, E. J Johnson, S. Devaraj, I. Jialal, and A. H Lichtenstein Plasma antioxidant capacity in response to diets high in soy or animal protein with or without isoflavones Am. J. Clinical Nutrition, January 1, 2005; 81(1): 43 - 49. [Abstract] [Full Text] [PDF] |
||||