Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064, USA.
J Alzheimers Dis. 2012;28(2):433-41. doi: 10.3233/JAD-2011-111307.
Neprilysin-2 (NEP2), a close homolog of neprilysin (NEP), degrades amyloid-β (Aβ) and serves an important role in clearing Aβ in vivo. We measured NEP2 and NEP mRNA levels from non-impaired (NI), mild cognitive impaired (MCI), and clinical Alzheimer's disease (AD) subjects in the mid-temporal gyrus, mid-frontal gyrus, caudate, and cerebellum. NEP2 activity levels were also determined. Our results indicate that NEP2 and NEP mRNA expression is altered in MCI subjects relative to NI subjects in AD-susceptible regions. NEP2 enzymatic activity was lowered in association with MCI and AD and was positively associated with cognitive function, independent of diagnostic category. Our finding that NEP2 expression and activity are altered in MCI is significant as these changes may potentially serve as preclinical markers for AD and reduced NEP2 activity may be associated with the development of AD.
脑啡肽酶 2（NEP2）是脑啡肽酶（NEP）的近缘同源物，可降解淀粉样蛋白-β（Aβ），并在体内清除 Aβ 中发挥重要作用。我们测量了来自非损伤（NI）、轻度认知障碍（MCI）和临床阿尔茨海默病（AD）患者的中颞叶、中额叶、尾状核和小脑的 NEP2 和 NEP mRNA 水平。还测定了 NEP2 活性水平。我们的结果表明，与非损伤对照相比，NEP2 和 NEP mRNA 表达在 AD 易感区域的 MCI 患者中发生改变。NEP2 酶活性与 MCI 和 AD 相关降低，与认知功能呈正相关，与诊断类别无关。我们发现，在 MCI 中 NEP2 的表达和活性发生改变，这是有意义的，因为这些变化可能潜在地作为 AD 的临床前标志物，而 NEP2 活性降低可能与 AD 的发展有关。
