The impact of aging on the brain in humans: A comprehensive review

Öz

Abstract The human brain is an approximately three-pound organ and serves as the ultimate command center of the human body through the sensory, motor and autonomic nervous systems. Aging is a complex process involving many molecular and metabolic events. There are many theories that try to explain this process. These theories cannot be considered in isolation and are interconnected. During the aging process, functional decline occurs in many organs. In this process, the brain is subjected to changes at histological, physiological and molecular levels. The main morphological changes seen with aging include brain volume loss, gray and white matter atrophy, cortical thinning, loss of gyrification and ventricular enlargement. The cellular, morphological and functional changes that occur in the brain with aging have been reported to be caused by molecular changes, especially in neurons and glia cells. Brain aging is known to be the greatest risk factor for various neurodegenerative diseases, including Alzheimer's and Parkinson's diseases, which are known to be a major public health problem. Therefore, it is important to understand the mechanism of brain aging. This review focuses on the histological, physiological, and molecular changes that occur in the brain during the aging process. Key words: Aging, Brain, Alzheimer's disease, Parkinson's disease

Anahtar Kelimeler

• Aging
• Brain
• Alzheimer's disease
• Parkinson's disease

İnsanlarda yaşlanmanın beyin üzerindeki etkisi: Kapsamlı bir inceleme

Öz

Özet İnsan beyni yaklaşık olarak üç kiloluk bir organdır ve duyusal, motor ve otonom sinir sistemleri aracılığıyla insan vücudunun en üst düzey komuta merkezi olarak hizmet etmektedir. Yaşlanma birçok moleküler ve metabolik olayın içerisinde bulunduğu kompleks bir süreçtir. Bu süreci açıklamaya çalışan birçok teori bulunmaktadır. Bu teoriler tek başına düşünülemez ve birbiriyle bağlantılıdır. Yaşlanma sürecinde, birçok organda fonksiyonel gerileme meydana gelmektedir. Bu süreçte beyinde histolojik, fizyolojik ve moleküler düzeyde değişime maruz kalmaktadır. Yaşlanmayla birlikte görülen başlıca morfolojik değişiklikler arasında beyin hacmi kaybı, gri ve beyaz madde atrofisi, kortikal incelme, girifikasyon kaybı ve ventriküler genişleme yer almaktadır. Yaşlanmayla beyinde meydana gelen hücresel, morfolojik ve fonksiyonel değişikliklere özellikle nöron ve glia hücrelerinde gerçekleşen moleküler değişimlerin neden olduğu bildirilmiştir. Beyin yaşlanmasının, büyük bir halk sağlığı sorunu olduğu bilinen Alzheimer ve Parkinson hastalıkları da dahil olmak üzere çeşitli nörodejeneratif hastalıklar için en büyük risk faktörü olduğu bilinmektedir. Bu nedenle beynin yaşlanma mekanizmasının anlaşılması önemlidir. Bu derlemede yaşlanma sürecinde beyinde meydana gelen histolojik, fizyolojik ve moleküler değişiklikler üzerine odaklanmaktadır. Anahtar kelime: Yaşlanma, Beyin, Alzheimer hastalığı, Parkinson hastalığı

Anahtar Kelimeler

• Yaşlanma
• Beyin
• Alzheimer hastalığı
• Parkinson hastalığı

Kaynakça

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