Laboratori de Química Farmacèutica, Unitat Associada al CSIC, Facultat de Farmàcia, and Institut de Biomedicina, Universitat de Barcelona, Barcelona, Spain.
Neurodegener Dis. 2012;10(1-4):96-9. doi: 10.1159/000333225. Epub 2012 Jan 6.
Multifactorial diseases such as Alzheimer's disease (AD) should be more efficiently tackled by drugs which hit multiple biological targets involved in their pathogenesis. We have recently developed a new family of huprine-tacrine heterodimers, rationally designed to hit multiple targets involved upstream and downstream in the neurotoxic cascade of AD, namely β-amyloid aggregation and formation as well as acetylcholinesterase catalytic activity.
In this study, the aim was to expand the pharmacological profiling of huprine-tacrine heterodimers investigating their effect on muscarinic M(1) receptors as well as their neuroprotective effects against an oxidative insult.
Sprague-Dawley rat hippocampus homogenates were used to assess the specific binding of two selected compounds in competition with 1 nM [(3)H]pirenzepine (for M(1) receptors) or 0.8 nM [(3)H]quinuclidinyl benzilate (for M(2) receptors). For neuroprotection studies, SHSY5Y cell cultures were subjected to 250 μM hydrogen peroxide insult with or without preincubation with some huprine-tacrine heterodimers.
A low nanomolar affinity and M(1)/M(2) selectivity has been found for the selected compounds. Huprine-tacrine heterodimers are not neurotoxic to SHSY5Y cells at a range of concentrations from 1 to 0.001 μM, and some of them can protect cells from the oxidative damage produced by hydrogen peroxide at concentrations as low as 0.001 μM.
Even though it remains to be determined if these compounds act as agonists at M(1) receptors, as it is the case of the parent huprine Y, their low nanomolar M(1) affinity and neuroprotective effects expand their multitarget profile and increase their interest as disease-modifying anti-Alzheimer agents.
阿尔茨海默病（AD）等多因素疾病，应该通过作用于多个参与发病机制的生物学靶点的药物来更有效地治疗。我们最近设计并合成了一类新的 huprine-tacrine 杂二聚体，旨在作用于 AD 神经毒性级联反应中上游和下游的多个靶点，包括β-淀粉样蛋白聚集和形成以及乙酰胆碱酯酶的催化活性。
在这项研究中，我们旨在扩展 huprine-tacrine 杂二聚体的药理学特性研究，评估其对毒蕈碱 M1 受体的作用及其对氧化应激损伤的神经保护作用。
使用 Sprague-Dawley 大鼠海马匀浆，评估两种选定化合物与 1 nM [(3)H]pirenzepine（用于 M1 受体）或 0.8 nM [(3)H]quinuclidinyl benzilate（用于 M2 受体）竞争结合的特异性结合。对于神经保护研究，用 250 μM 过氧化氢处理 SHSY5Y 细胞培养物，并用或不用一些 huprine-tacrine 杂二聚体进行预孵育。
所选化合物对 M1 受体具有低纳摩尔亲和力和 M1/M2 选择性。在 1 至 0.001 μM 的浓度范围内，huprine-tacrine 杂二聚体对 SHSY5Y 细胞没有神经毒性，其中一些杂二聚体在 0.001 μM 的浓度下即可保护细胞免受过氧化氢产生的氧化损伤。
尽管这些化合物是否作为 M1 受体的激动剂（如母体 huprine Y）作用仍有待确定，但它们对 M1 受体的低纳摩尔亲和力和神经保护作用扩展了它们的多靶点特性，并增加了它们作为疾病修饰性抗阿尔茨海默药物的应用前景。
