Çeşitli antioksidanların sıçan beyni üzerindeki etkilerinin moleküler düzeyde incelenmesi


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Türkiye

Tezin Onay Tarihi: 2003

Tezin Dili: İngilizce

Öğrenci: Sara Banu Akkaş

Danışman: FERİDE SEVERCAN

Özet:

The brain is highly susceptible to free radical damage since it is rich in polyunsaturated fatty acids and consumes very high amounts of oxygen. In this study, the effects on rat brain tissue of several antioxidants, namely lipoic acid, vitamin E and melatonin, were examined as the control studies of further research, in which their ability to protect the rat brain tissue from oxidative stress will be investigated. The tool of investigation selected was Fourier Transform Infrared Spectroscopy (FTIR) because of its ability to monitor the microenvironment of biomolecules. The examination of the melatonin treated rat brain crude membrane showed that melatonin induced a significant increase in the lipid to protein ratio of the lipid system and the frequency values of the PO2- symmetric stretching mode. The overall observations suggest that even a single dose of melatonin might induce a fluidifying effect on the lipid bilayer at body temperature and in consequence ease the interaction of antioxidants with lipid radicals. The effect of dietary administration of lipoate on rat brain caused a significant increase in the PO2- asymmetric vibrational mode frequency and increased the lipid content. The observations suggest that lipoic acid might induce a destabilizing effect on the membranous system. The effect of dietary administration of vitamin E on rat brain decreased the overall amount of lipids and the frequencies of the bands of the functional groups of the lipid bilayer. These results suggest a stabilizing effect of vitamin E on the state-of-order of the lipid bilayer.