An oxidized/reduced state of plasma albumin reflects malnutrition due to an insufficient diet in rats.
We examined whether protein- and food-intake restrictions modulate the oxidized/reduced state of plasma albumin in Sprague-Dawley rats. Rats were fed a 3%, 5%, 10% or 20% casein diet for 2 weeks. The plasma albumin concentration significantly decreased with decreasing protein intake. However, no significant difference in plasma albumin concentration was seen between rats fed the 5% or 10% casein diet. In rats fed the 5% casein diet, the percentage of mercaptalbumin within total plasma albumin was significantly lower and that of nonmercaptalbumin-1 was significantly higher than in rats fed the 10% casein diet. In experiments with food-intake restriction for 2 weeks, rats were fed 50% or 75% of the amount of a 20% casein diet consumed by control rats. The percentage of mercaptalbumin was significantly lower and that of nonmercaptalbumin-2 was significantly higher in rats with food-intake restriction than in control rats. When rats with malnutrition were refed with the 20% casein dietad libitum, the percentage of mercaptalbumin rapidly increased. The change in the percentage of mercaptalbumin was correlated with the plasma transthyretin concentration. These results indicate that the oxidized/reduced state of plasma albumin may be applied as a sensitive marker of nutritional status reflecting dietary pattern.
Departments of Nutrition Science, Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, 1-5 Shimogamo-hangi-cho, Sakyo, Kyoto 606-8522, Japan.
Masashi
M
Kuwahata
Departments of Nutrition Science, Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, 1-5 Shimogamo-hangi-cho, Sakyo, Kyoto 606-8522, Japan.
Mari
M
Hasegawa
Departments of Nutrition Science, Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, 1-5 Shimogamo-hangi-cho, Sakyo, Kyoto 606-8522, Japan.
Yukiko
Y
Kobayashi
Nutritional Science Institute, Morinaga Milk Industry Co., Ltd., 5-1-83 Higashihara, Zama, Kanagawa 252-8583, Japan.
Yasuaki
Y
Wada
Departments of Nutrition Science, Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, 1-5 Shimogamo-hangi-cho, Sakyo, Kyoto 606-8522, Japan.
Yasuhiro
Y
Kido
insufficient diet; malnutrition; rats; reduced albumin; transthyretin