Kolesterol düşürücü simvastatinin farklı sıçan iskelet kas dokuları üzerindeki etkilerinin moleküler düzeyde incelenmesi.


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Edebiyat Fakültesi, Biyolojik Bilimler Bölümü, Türkiye

Tezin Onay Tarihi: 2007

Tezin Dili: İngilizce

Öğrenci: Nihal Şimşek Özek

Danışman: FERİDE SEVERCAN

Özet:

In the present study Fourier Transform Infrared (FTIR) and Attenuated Total Reflectance FTIR (ATR-FTIR) Spectroscopy were used to examine the effects of simvastatin on structure, composition and function of macromolecules of three different rat skeletal muscles EDL (Extensor Digitorium Longus), DIA (Diaphragm) and SOL (Soleus) containing different amount of slow and fast twitch fibers, at molecular level. Simvastatin, a lipophilic statin, is widely used in the treatment of hypercholesterolemia and cardiovascular diseases due to its higher efficacy. However, long term usage of statins give rise to many adverse effects on different tissues and organs. Skeletal muscle accounts for around 45 % of the total body weight and has a high metabolic rate and blood flow. As a consequence, it is highly exposed to drugs within the circulation. Therefore, it is one of the target tissues of statins. The two main types of muscle fibers are type I (slow-twitch) and type II (fast-twitch) fibers; having different structural organization and metabolic features. EDL is a fast twitch muscle while SOL is slow twitch muscle. On the other hand, DIA shows intermediate properties between slow and fast twitch muscle. The results of ATR-FTIR and FTIR spectra revealed a considerable decrease in protein and lipid content of simvastatin treated skeletal muscles, indicating protein breakdown or decreased protein synthesis and increased lipolysis. Moreover changes in protein structure and conformation were observed. In simvastatin treatment, muscle membrane lipids were more ordered and the amount of unsaturated lipids was decreased possibly due to lipid peroxidation. The drug treatment caused a decrease in the content of nucleic acids, especially RNA, and hydrogen and non-hydrogen bonded phospholipids in the membrane structures of skeletal muscles. In all of the spectral parameters investigated EDL muscle was more severely affected from statin treatments while SOL was less affected from the drug treatments. Thus, FTIR and ATR-FTIR spectroscopy appear to be useful methods to evaluate the effects of statin on skeletal muscle tissues at molecular level.