Savu L, Vranckx R, Rouaze-Romet M, Maya M, Nunez E A, Tréton J, Flink I L
U.224, INSERM Faculté de Médecine Xavier Bichat, Laboratoire de Biochimie, Paris, France.
Biochim Biophys Acta. 1991 Jul 26;1097(1):19-22. doi: 10.1016/0925-4439(91)90017-4.
Thyroxine-binding globulin (TBG), the major carrier of thyroid hormones in human serum, was thought to be absent in most species, including rodents. We demonstrated recently that in fact the rat possesses a TBG gene, virtually non-expressed in young adults, but actively transcribed during post-natal development. We now find that the TBG gene is also increasingly re-expressed during senescence. Evidence is presented suggesting that physiologically decreased thyroid hormone levels, characteristic of neonates and of ageing rats, might constitute a common factor inducing up-regulation of TBG in both developmental and ageing processes. Rat TBG is to our knowledge the first biochemical 'positive' (i.e. increasing) marker of non-pathological senescence, expressed at both biosynthetic and bloodstream levels.
甲状腺素结合球蛋白（TBG）是人类血清中甲状腺激素的主要载体，过去人们认为在包括啮齿动物在内的大多数物种中都不存在。我们最近证明，事实上大鼠拥有一个TBG基因，在年轻成年大鼠中几乎不表达，但在出生后发育过程中会活跃转录。我们现在发现，TBG基因在衰老过程中也会越来越多地重新表达。有证据表明，新生儿和衰老大鼠所特有的甲状腺激素水平生理性下降，可能是在发育和衰老过程中诱导TBG上调的一个共同因素。据我们所知，大鼠TBG是第一个非病理性衰老的生化“阳性”（即增加）标志物，在生物合成和血液水平上均有表达。
