Statinlerin Nöroloji Pratiğindeki Yeri

Abstract

Statinler, 3-hidroksi–3-metilglutaril koenzim A (HMG-CoA) redüktaz inhibisyonu sayesinde karaciğerde hücre içerisinde LDL-kolesterol seviyesinde azalma sağlarlar. Bu durum karaciğer hücre yüzeyindeki LDL reseptör sayısının artmasına, dolayısıyla plazma LDL seviyelerinin düşmesine neden olur. Ayrıca statinler LDL’nin periferden absorbsiyonunu artırarak karaciğer hücrelerine ve diğer hücrelere girişini ve orada yıkımını artırarak kolesterol seviyesini azaltırlar.Statinlerin kolesterol düşürücü etkilerinin yanı sıra inflamasyon ve oksidasyon, hücre proliferasyonu, endotel fonksiyonları, koagülasyon ve trombosit sistemi üzerine de etkili olduğu gösterilmiştir.Kolesterol artışı ile koroner arter hastalığı arasında ilişki olduğu ve aynı zamanda kolesterol düşürücü tedavinin koroner arter hastalığının önlenmesi ve tedavisindeki önemi değişik çalışmalarla ortaya konmuştur. Benzer mekanizmalarla hiperkolesteroleminin inmede rol oynadığı gösterilmiştir. Bunun dışında multiple skleroz, demans gibi inme dışındaki nörolojik hastalıkların etyolojisinde hiperkolesteroleminin oynadığı rol son zamanlarda araştırılmaya başlanmıştır. Tüm bu çalışmaların sonunda statinlerin nörolojik hastalıklarda kullanımıyla ilgili daha fazla randomize, kontrollü çalışmaya ihtiyaç olduğu sonucuna varılmıştır. Role of statins in the practice of clinic neurology Statins reduce the level of LDL-cholesterol in liver cells by inhibiting 3-hydroxy 3-methylglutaryl coenzyme A (HMG-COA) reductase. This causes an increase of the number of the LDL receptors located on liver cell surfaces and thus there is a decrease in plasma LDL levels. Statins also cause an increase in the peripheral absorbtion of LDL and more LDL enters liver cells where it is destructed causing a reduction in cholesterol levels.Besides their cholesterol reducing effects, statins have been assessed as having functions in inflamation and oxidation, cell proliferation, endothelial functions, coagulation and platelet systems. Various studies have put forward a relationship between cholesterol increase and coronory artery disease. It has also been documented that cholesterol reducing therapy is important in the preventation and cure of coronory artery disease. Using similar mechanisms, it has also been shown that hypercholesterolemia also plays an important role in the evalation of stroke.Recently, studies investigating the role of hypercholesterolemia in the etiologies of neurological diseases other than stroke such as multiple sclerosis and dementia have been designed also. Results of studies concerning the usage of statins in neurological diseases have led to a conclusion that more randomised and controlled studies are needed.

Keywords

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