A study on detoxication of dietary products of lipid peroxidation in digestive tract.

本文研究了大鼠消化道对脂质过氧化产物的解毒能力。建立了一种用高效液相色谱法定量检测动物胃和肠中过氧化产物的方法。口服给药的亚油酸氢过氧化物很容易在胃中消失。一部分被还原为羟基亚油酸或分解为醛类，然后转移到空肠，进入体内。其余的转化为酮-环氧-十八碳烯酸，留在胃粘膜上。当三亚油酸氢过氧化物口服给药时，它们在胃中消失的速度比亚油酸氢过氧化物慢。由于三亚油酸甘油酯过氧化氢在胃中被脂肪酶水解为亚油酸过氧化氢，因此认为它们也被分解为醛，然后转移到空肠并掺入体内。高脂、高蛋白、高碳水化合物饮食大鼠胃内过氧化氢三亚油酸甘油酯的消失率不受营养条件的影响。因此，脂质过氧化氢在胃中分解为醛，醛被并入体内。因此，可以得出结论，脂质过氧化的膳食产品的毒性，必须是由于其代谢产物。我已经明确了膳食醛类对大鼠的肝毒性。通过该项目，确定了甘草产物的主要成分9-氧代壬酸被掺入肝脏。然后，关于9-氧代壬酸作为体内生物信号之一的作用的另一研究正在进行中。

Detoxifying ability of digestive tract for dietary products of lipid peroxidation was investigated in rats. The method for quantitative detection of peroxidation products from the animal stomach and intestines was estimated using a HPLC equipped with an amperometer and a UV detector. Linoleic acid hydroperoxides dosed orally easily disappeared in the stomach. A part of them was reduced to hydroxy linoleic acid or decomposed to aldehydes, and then transferred to jejunum and incorporated into body. The others were changed to keto-epoxy-octadecaenoic acid and remained in the gastric membrane. When trilinolein hydroperoxides were dosed orally, they disappeared in the stomach more slowly than linoleic acid hydroperoxides. Because trilinolein hydroperoxides were hydrolyzed to linoleic acid hydroperoxides in the stomach by lipase, it was considered that they were also decomposed to aldehydes, and then transferred to jejunum and incorporated into body. The disappearing rate of trilinolein hydroperoxides in the stomach was not affected by the nutritional conditions of rats on such a diet as high-lipid, high-protein, or high-carbohydrate. Thus, lipid hydroperoxides were decomposed in the stomach to aldehydes, which were incorporated into the body. It was therefore concluded that the toxicity of dietary products of lipid peroxidation must be due to their aldehydic products. I have already been made clear the hepatotoxicity by dietary aldehydes in the rats. By this project, a major components of the aldehydic products, 9-oxononanoic acid, was determined to be incorporated into liver. Then, another study on a role of 9-oxononanoic acid as one of bio-signals in the body is in progress.