金属巯蛋白在不同年龄大鼠肝脏中的表达(英文)

Age-difference in hepatic metallothionein expression in rats

目的金属硫蛋白(MT)是富含半胱氨酸的短肽,对多种重金属有高度亲和性。它对维持铜和锌的内环境稳定,防止重金属毒性和氧化应激起着重要的作用。本研究旨在探讨年龄对肝脏MT-1和MT-2的mRNA水平的影响。方法从发育(-2,1,7,14,21,28,35和60d),老龄化(28,60,180,540和800d),妊娠和哺乳大鼠肝脏中分离总RNA,并用实时定量RT-PCR法分析MT的表达。结果胎鼠(-2d)和新生鼠的MT mRNA水平高,出生7d达到高峰,随后随着年龄的增长而下降。以雄性MT-1为例,在21d断奶时其mRNA水平比-2d降低了10倍,800d时降低220倍;雄性比雌性的表达水平高。妊娠晚期MT表达减少。分娩时MT的表达反弹,但哺乳期间再次下降。结论 MT mRNA水平受一系列生理因素所影响,如发育,老龄化,性别,妊娠,哺乳和时辰。这些变化会影响人体抗衰老及对有毒物质的防御功能。

Objective This study was aimed to examine physiological variations in mRNA levels of metallothio- nein （MT） during the development, ageing, gender, pregnancy and lactation. Methods Livers from SD rats dur- ing development （ -2, 1, 7, 14, 21, 28, 35, and 60 days） and ageing （28, 60, 180, 540 and 800 days） were collected. Total RNA was isolated, and subjected to real - time RT - PCR analysis. Results The mRNA levels of MT - 1 and MT - 2 were detected in fetal livers （ - 2 days）, slightly decreased at birth, but quickly peaked at 7 days of age. MTs were then decreased thereafter. For example, MT - 1 mRNA in males decreased l0 - fold at 21 days of age, and continued to decrease to 220 - fold at 800 days, as compared to 7 days of age. MT - 2 mRNA slightly increased at 60 days of age, then keeping decreases to 800 days of age. Males had higher MT mRNAs than females. In pregnancy and lactating rats, MT mRNAs decreased at late gestation clays （GD14 and GD19）. MT mRNA levels were rebound at birth, but again decreased during lactation. Conclusion MT expres- sion is significantly altered by physiological factors, such as the development, ageing, sex, pregnancy and lacta- tion, which could impact the body defense against toxic stimuli and ageing.