Departamento de Ciencias Clínicas Veterinarias, Facultad de Veterinaria de Lugo, Universidad de Santiago de Compostela, 27002 Lugo, Spain.
Exp Gerontol. 2011 Jul;46(7):590-6. doi: 10.1016/j.exger.2011.02.013. Epub 2011 Mar 3.
Aging dogs naturally demonstrate cognitive impairment and neuropathology that model early Alzheimer's disease (AD). In particular, there is evidence that canine cognitive dysfunction syndrome (CDS) in aged dogs is accompanied by cortical deposition of Aβ peptides and neurodegeneration. Plasma Aβ levels have been examined in humans as putative biomarkers for AD, but to date, no similar studies have been conducted for canine dementia. The aim of the present study was to assess plasma Aβ1-42 and Aβ1-40 levels in a blind study using pet dogs that were either successfully aging or exhibiting CDS. The severity of cognitive impairment was assessed using an owner-based questionnaire. On average, young dogs presented significantly higher plasma levels of Aβ1-42 and Aβ1-40 than aged, cognitively unimpaired dogs. Notably, among aged dogs, the levels of Aβ1-42 and the Aβ42/40 ratio were significantly higher in those showing mild cognitive impairment than in either cognitively unimpaired or severely affected dogs. These results suggest that increased plasma Aβ1-42 levels and Aβ42/40 ratio could be a biomarker for canine cognitive dysfunction, which is considered an excellent natural model of early AD.
衰老的狗自然会表现出认知障碍和神经病理学，这些病理模型可模拟早期阿尔茨海默病（AD）。特别是，有证据表明，老年犬的犬认知功能障碍综合征（CDS）伴随着 Aβ 肽在皮质中的沉积和神经退行性变。人类的血浆 Aβ 水平已被作为 AD 的潜在生物标志物进行了检查，但迄今为止，尚未对犬类痴呆症进行类似的研究。本研究的目的是使用经过盲法评估的宠物狗来评估成功衰老或表现出 CDS 的狗的血浆 Aβ1-42 和 Aβ1-40 水平。认知障碍的严重程度使用基于主人的问卷进行评估。平均而言，年轻的狗的血浆 Aβ1-42 和 Aβ1-40 水平明显高于认知功能未受损的老年狗。值得注意的是，在老年狗中，轻度认知障碍的狗的 Aβ1-42 水平和 Aβ42/40 比值明显高于认知功能未受损或严重受损的狗。这些结果表明，血浆 Aβ1-42 水平和 Aβ42/40 比值的增加可能是犬认知功能障碍的生物标志物，而犬认知功能障碍被认为是早期 AD 的极好自然模型。
