Mote P L, Grizzle J M, Walford R L, Spindler S R
Department of Biochemistry, University of California, Riverside.
J Gerontol. 1991 May;46(3):B95-100. doi: 10.1093/geronj/46.3.b95.
The influence of age and life-span-prolonging caloric restriction on the expression of hepatic genes for xenobiotic and activated oxygen metabolism was investigated in female C3B10RF1 mice, a long-lived hybrid strain. Animals were fed either ad libitum, or diets reduced 20% or 52% in total calories but approximately unchanged in total protein, vitamins, and minerals. Cytochrome P1- and P3-450 (cyp1A1 and cyp1A2, respectively) mRNA levels decreased approximately 40% between age 4-5 months (young) and 30-31 months (old) in ad libitum fed animals (p less than or equal to .05). Caloric restriction eliminated this decrease. Manganese-superoxide dismutase mRNA decreased significantly in old ad libitum fed mice, and caloric restriction eliminated this decrease. No change in manganese-superoxide dismutase activity was detected, probably due to its low level and the large variability inherent in the assay. Catalase mRNA increased with age, but was not affected by diet. Catalase activity increased significantly with caloric restriction in young and old mice, in the absence of an increase in catalase mRNA, suggesting translational or posttranslational effects. CuZn-superoxide dismutase, glutathione peroxidase and epoxide hydrolase mRNA, and the ratio of ribosomal to total mRNA did not change with age or diet.
在长寿杂交品系雌性C3B10RF1小鼠中,研究了年龄和延长寿命的热量限制对肝脏中异生素和活性氧代谢相关基因表达的影响。动物被分为三组,分别给予自由采食饮食,或总热量减少20%或52%但总蛋白质、维生素和矿物质含量大致不变的饮食。在自由采食的动物中,4 - 5个月龄(年轻)和30 - 31个月龄(年老)之间,细胞色素P1 - 450和P3 - 450(分别为cyp1A1和cyp1A2)的mRNA水平下降了约40%(p≤0.05)。热量限制消除了这种下降。在年老的自由采食小鼠中,锰超氧化物歧化酶的mRNA显著下降,热量限制消除了这种下降。未检测到锰超氧化物歧化酶活性的变化,可能是由于其水平较低以及该检测方法固有的较大变异性。过氧化氢酶的mRNA随年龄增加,但不受饮食影响。在年轻和年老小鼠中,热量限制显著增加了过氧化氢酶活性,而此时过氧化氢酶的mRNA并未增加,这表明存在翻译或翻译后效应。铜锌超氧化物歧化酶、谷胱甘肽过氧化物酶和环氧化物水解酶的mRNA以及核糖体与总mRNA的比例均未随年龄或饮食而变化。