Aretheus’un Tanımladığı Demans, Bugünkü Hali ile Alzheimer Hastalığının İnsan ve Köpeklerde Çift Yönlü Benzerlikleri

Year 2025, Volume: 6 Issue: 2, 102 - 115, 30.09.2025

Hasan Erdoğan , Tahsin Barış Değer , Songül Erdoğan , Serdar Paşa , Cansu Balıkçı , İlayda Tendar , Ayşe İdil Kizilkanat , Pelin Dinç , Kerem Ural

Abstract

Alzheimer hastalığı (AH), insanlarda olduğu gibi hayvan modellerinde de karmaşık nörodejeneratif süreçlerle kendini gösterir. Hastalığın temel patolojik özellikleri arasında amiloid beta (Aβ) birikimi, tau protein hiperfosforilasyonu, sinaptik işlev bozukluğu ve bilişsel disfonksiyon yer alır. İnsan AH’sini anlamak için geliştirilen hayvan modelleri, bu patolojilerin mekanizmalarını ve hastalığın ilerleyişini incelemek için değerli araçlar sunmaktadır. Transgenik fare modelleri, genetik modifikasyonlar yoluyla Aβ birikimi ve tau protein değişikliklerini taklit ederek hastalığın moleküler ve hücresel düzeyde incelenmesini sağlar. Bu modeller, özellikle erken evre patolojik değişiklikleri ve ilaç geliştirme süreçlerini araştırmada kritik rol oynamaktadır. Doğal yaşlanma süreçlerine bağlı olarak bilişsel bozukluklar gösteren köpekler ve kediler, insan Alzheimer patolojisini daha yakından taklit eden önemli modellerdir. Özellikle yaşlı köpeklerde, beyinde Aβ plak oluşumu, sinaptik kayıplar ve nörodejenerasyon gibi değişiklikler gözlemlenir. Köpeklerin bilişsel işlevleri üzerinde yapılan davranışsal testler, insanlarda görülen öğrenme ve hafıza bozukluklarını değerlendirmek için kullanılabilir. Kedilerde de benzer nöropatolojik süreçler rapor edilmiştir, ancak bu alandaki çalışmalar daha sınırlıdır. Hayvan modelleri, insan ve hayvanlar arasında bazı fizyolojik farklılıklar bulunsa da, Alzheimer hastalığının biyolojik temellerini anlamak ve tedavi stratejileri geliştirmek için önemli bilgiler sunar. Ancak, türler arası farklılıklar göz önünde bulundurularak bu modeller dikkatle seçilmeli ve yorumlanmalıdır. Bu modeller, Alzheimer’ın karmaşık doğasını çözümlemeye katkıda bulunurken, yeni terapötik yaklaşımların geliştirilmesine yönelik klinik araştırmalara sağlam bir temel oluşturmaktadır.

Keywords

Alzheimer , amiloid beta , bilişsel disfonksiyon , hayvan modelleri , tau protein

Dementia as Described by Aretheus, Its Current Form and the Bilateral Similarities of Alzheimer's Disease in Humans and Dogs

Abstract

Alzheimer's disease (AD) manifests itself with complex neurodegenerative processes in animal models as well as in humans. The basic pathological features of the disease include amyloid beta (Aβ) accumulation, tau protein hyperphosphorylation, synaptic dysfunction, and cognitive dysfunction. Animal models developed to understand human AD provide valuable tools to study the mechanisms of these pathologies and the progression of the disease. Transgenic mouse models mimic Aβ accumulation and tau protein changes through genetic modifications, allowing the disease to be studied at the molecular and cellular levels. These models play a critical role in investigating early-stage pathological changes and drug development processes. Dogs and cats, which exhibit cognitive impairment due to natural aging processes, are important models that more closely mimic human AD pathology. Changes such as Aβ plaque formation, synaptic losses, and neurodegeneration are observed in the brain, especially in older dogs. Behavioral tests performed on the cognitive functions of dogs can be used to evaluate learning and memory impairments seen in humans. Similar neuropathological processes have been reported in cats, but studies in this area are more limited.
Animal models provide important information for understanding the biological basis of Alzheimer's disease and developing treatment strategies, despite some physiological differences between humans and animals. However, these models should be carefully selected and interpreted, considering species differences. These models contribute to unraveling the complex nature of Alzheimer's disease and provide a solid basis for clinical research to develop new therapeutic approaches.

Keywords

Alzheimer , amyloid beta , animal models , cognitive dysfunction , tau protein

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