松果腺在衰老过程中的地位与褪黑素的作用

目的论述松果腺及褪黑素与机体衰老的因果关系 ,进而提出衰老的松果腺学说。方法 1 本学说提出的背景 ;2 松果腺学说的实验依据 ;3 褪黑素的机能调节作用与抗衰老机理。结果与结论 1 松果腺学说的内容 :衰老源于松果腺形态和功能的变化 ,然后扩展到全身组织细胞 ,呈现多种退行性体征。补充外源性褪黑素或移植松果腺 ,可以延缓老化 ,增长动物寿命。 2 松果腺和褪黑素是年龄变化的函数。随着松果腺钙化 ,褪黑素合成与分泌减少 ,生物节律变得不稳定 ,适应内外环境能力降低。褪黑素在生物界分布极为广泛 ,它作为进化保留分子使机体与环境保持协调统一。褪黑素可在多方面发挥作用 ,通过矫正生物钟功能、调节神经内分泌活动、清除自由基、增强免疫、抗应激、保护遗传物质和促进衰老相关基因表达等 ,起到抗衰老作用。 3 最后阐述松果腺学说的理论意义和应用前景。

Role of the pineal gland and the effects of melatonin in aging processes

Objective To reveal the role of the pineal gland and the actions of melatonin (MT)in the senile process, and then the pineal hypothesis of aging was suggested by us. Methods (1) Background for advancing this new hypothesis; (2) Gerontological, physiological and morphological experiments of the pineal gland backing up the new hypothesis; (3) The anti aging action of MT. Results and Conclusions (1) The main point of pineal hypothesis: Aging is pineal failure, and administering exogenous MT may keep homeostasis with age and. prolong the life span. (2) Experimental evidences: Pineal and MT changes are a function of age in animals and human beings as well. Growing pineal calcification and reducing biosynthesis of MT with age, circadian rhythms become increasingly unsteady. Then, a series of retrograde changes expands to the whole body, which may be defined as aging. MT administrated or pineal grafted was able to prolong the lifespan of rodent. MT is widely distributed over lots of living organisms. MT plays its anti aging role in the following points: correcting biological clock to synchronize with the environment, scavenging free radical, modulating neuroendocrine, anti stress, improving immunity, preventing nuclear DNA damage and so forth. MT may be useful for the treatment of diseases related to premature aging, and for stimulation c fos gene expression in suprachiasmatic nuclear. 3. The significance and foreground of pineal hypothesis of aging was eludicated.