The Glymphatic System

Year 2024, Volume: 3 Issue: 3, 102 - 110, 01.10.2024

İlknur Çöllü , Ozan Turamanlar

https://doi.org/10.59518/farabimedj.1420088

Abstract

The glymphatic system was named based on its similarity to the lymphatic system in peripheral tissue and the important role of glial aquaporin-4 channels in fluid transport. Although the lymphatic system in the human body was described towards the end of the eighteenth century, for many years the existence of a lymphatic system in the brain was ignored. Since the second half of the twentieth century, attempts have been made to explain the existence of a functional lymphatic system within the central nervous system. In recent experimental studies, the perivascular exchange movement of cerebrospinal fluid and intercellular fluid within the central nervous system was demonstrated by observing the path of a fluorescent dextrans tracer injected into the cisterna magna of the mouse, and it was suggested that this system should be called the "glymphatic" system. Recently, the mechanisms directing the glymphatic flow have been tried to be explained. The relationship of the glymphatic system with the cardiac and respiratory cycles as well as with vasodynamic changes, sleep and body posture-related changes has been demonstrated by experimental studies. In addition, in recent years, a large number of studies have been conducted on the relationship between the glymphatic system and many pathological conditions, diseases and syndromes such as subarachnoid hemorrhage, aging, small vessel disease and hypertension, Alzheimer's disease, Parkinsonism, depression and obesity and treatment options through the glymphatic system. The aim of this review is to introduce the glymphatic system, its historical development, its role in physiological and pathological mechanisms, the importance of the glymphatic system in medical imaging methods and treatment approaches.

Keywords

the glymphatic system, perivascular space, aquaporin-4, astrocyte

Glenfatik Sistem

Abstract

Glenfatik sistem, periferik dokudaki lenfatik sisteme benzerliğine ve glial aquaporin-4 kanallarının sıvı taşınmasındaki önemli rolüne dayalı olarak adlandırılmıştır. On sekizinci yüzyılın sonlarına doğru insan vücudundaki lenfatik sistem tanımlanmış olmasına rağmen uzun yıllar boyunca beyinde lenfatik sistem varlığı göz ardı edilmiştir. Yirminci yüzyılın ikinci yarısından itibaren merkezi sinir sistemi içinde fonksiyonel bir lenfatik sistemin olduğu açıklanmaya çalışılmıştır. Yakın dönemde yapılan deneysel çalışmalarda, farenin cisterna magna’sına enjekte edilen floresan desktrandan oluşan izleyicinin takip ettiği yol gözlemlenerek, merkezi sinir sistemi içinde beyin omurilik sıvısı ve hücreler arası sıvının perivasküler değişim hareketi gösterilmiş ve bu sistemin "glymphatic" yol olarak adlandırılmasını önerilmiştir. Son zamanlarda glenfatik akımı yönlendiren mekanizmalar açıklanmaya çalışılmıştır. Glenfatik sistemin kardiyak ve solunum siklus ile ilişkilsinin yanında vazodinamik değişiklikler, uyku ve vücut duruşuna bağlı değişikliklerle olan ilişkisi yapılan deneysel çalışmalarla gösterilmiştir. Bunun yanında son yıllarda subaraknoid kanama, yaşlanma, küçük damar hastalığı ve hipertansiyon, Alzheimer, Parkinsonizm, depresyon ve obezite gibi birçok patolojik durum, hastalık ve sendromlarda glenfatik sistem ile olan ilişkisi ve glenfatik sistem yoluyla tedavi seçenekleri üzerine oldukça fazla sayıda araştırma yapılmıştır. Bu derlememizin amacı, glenfatik sistemi tanıtmak, bu sistemin tarihsel gelişiminden başlayarak günümüze kadar süregelen gelişimini, fizyolojik ve patolojik mekanizmalardaki rolünü, tıbbi görüntüleme yöntemleri ve tedavi yaklaşımlarında glenfatik sistemin önemini belirtmektir.

Keywords

glenfatik sistem, perivasküler boşluk, aquaporin-4, astrosit

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