Danenberg H D, Haring R, Fisher A, Pittel Z, Gurwitz D, Heldman E
Department of Organic and Medicinal Chemistry, Israel Institute for Biological Research, Ness-Ziona, Israel.
Life Sci. 1996;59(19):1651-7. doi: 10.1016/0024-3205(96)00496-1.
Dehydroepiandrosterone (DHEA), the major secretory product of the human adrenal cortex, significantly declines with advanced age. We have previously demonstrated that DHEA prevents the reduction in non-amyloidogenic APP processing, following prolonged stimulation of the muscarinic receptor, in PC12 cells that express the ml acetylcholine-receptor. The present study examined whether this effect may be mediated via modulation of APP metabolism. It was found that DHEA treatment increases the content of membrane-associated APP holoprotein by 24%, and the accumulation of secreted APP in the medium by 63%. No increase in viable cell number nor in nonspecific protein production was observed in DHEA-treated cells. Thus, DHEA seems to increase specifically both APP synthesis and secretion. We propose that the age-associated decline in DHEA levels may be related to the pathological APP metabolism observed in Alzheimer's disease.
脱氢表雄酮(DHEA)是人类肾上腺皮质的主要分泌产物,其水平会随着年龄的增长而显著下降。我们之前已经证明,在表达m1乙酰胆碱受体的PC12细胞中,长时间刺激毒蕈碱受体后,DHEA可防止非淀粉样前体蛋白(APP)加工过程的减少。本研究探讨了这种作用是否可能通过调节APP代谢来介导。结果发现,DHEA处理可使膜相关APP全蛋白的含量增加24%,并使培养基中分泌型APP的积累增加63%。在DHEA处理的细胞中,未观察到活细胞数量或非特异性蛋白质产生的增加。因此,DHEA似乎特异性地增加了APP的合成和分泌。我们推测,DHEA水平与年龄相关的下降可能与阿尔茨海默病中观察到的病理性APP代谢有关。