Biophysical investigation of the effects of antioxidants on normal and diabetic rat bone tissues at molecular level

Boyar, Handan
In the first part of this study, the effect of diabetes mellitus on the long bones (femur and tibia) of the streptozocin induced diabetic rats and the effect of selenium (Se) treatment on these bones are investigated at molecular level by Fourier transform infrared (FTIR) spectroscopy, light and electron microscopy. In the second part of this study, the effect of selenium and vitamin E deficiency or selenium toxicity on rat bones have been studied by FTIR spectroscopy. The results of the first part of the present study revealed that the changes observed in the mineral and matrix phases of diabetic bones, briefly, the increase in the mineral crystal size, the decrease in the acid phosphate and carbonate content, the increase in the ratio of pyridinoline [Pyr] cross-links to dihydroxylysinonorleucine [DHLNL] cross-links present in collagen I of the bone tissue as well as the increase in the lipid to protein ratio of the matrix are quite similar to those seen in osteoporotic patients and animal models and confirms the evidence of diabetic osteoporosis. Histologic studies carried out with light and electron microscopy supported these findings. FTIR spectroscopic analysis revealed that sodium selenite treatment had some restoring effects on the deviated properties of the microstructure of diabetic bones. The results of the second part of this study revealed that the deficiency of selenium led to increase in the crystal size of the bone minerals, decreases in acid phosphate and labile carbonate content and increase in the Pyr to DHLNL ratio as in the case of diabetic bones. These results can be indicative of the importance of selenium in glucose metabolism.The results of Se excess group are similar to those of Se deficient group except that toxic amount of selenium led to increase in the relative amount of acid phosphate. This can affect the pH of the mineral environment


The effect of diabetes on rat skeletal muscle tissues at molecular level
Bozkurt, Özlem; Severcan, Feride; Department of Biology (2006)
In the present study Fourier Transform Infrared Spectroscopy was used to examine the effects of streptozotocin-induced diabetes mellitus on the structural components of slow- and fast-twitch rat skeletal muscles, at molecular level. Diabetes mellitus is a chronic disorder of carbohydrate, fat and protein metabolism, which is characterized by hyperglycemia caused by a defective or deficient insulin secretory response. The effect of diabetes is seen on a variety of tissues leading to important secondary compl...
interaction of the non steroidal anti-inflammatory drug celecoxib with pure and cholesterol-containing model membranes
Sade, Aslı; Banerjee, Sreeparna; Department of Biology (2009)
The interactions of the non steroidal anti-inflammatory drug celecoxib with pure and cholesterol containing distearoyl phosphatidylcholine multilamellar vesicles were studied using Fourier transform infrared spectroscopy, differential scanning calorimetry and turbidity technique at 440 nm. The results reveal that celecoxib exerts opposing effects on membrane order in a concentration dependent manner while cholesterol disorders and orders the membrane in the gel and liquid crystalline phase, respectively. Te...
Interactions of cholesterol reducing agent simvastatin with charged phospholipid model membranes
Sarıışık, Ediz; Severcan, Feride; Department of Biology (2010)
Interactions of cholesterol reducing agent simvastatin with charged model membranes were investigated. Effects of cholestrol reducing agent simvastatin on the phase transition behaviour and physical properties of the anionic dipalmitoyl phosphatidylglycerol (DPPG) multilamellar liposome were studied as a function of temperature and simvastatin concentration. Moreover the effect of acyl chain length on the simvastatin model membrane interactions was monitored using dipalmitoyl phosphatidylglycerol (DPPG) and...
Molecular investigation of ptz-induced epileptic activities in rat brain cell membranes and the effects of vigabatrin
Görgülü Türker, Sevgi; Severcan, Feride; Department of Biology (2009)
The epilepsies are a heterogenous group of symptom complexes, whose common features is the recurrence of seizures. There is no certain therapy for epilepsy. In order to promote new advances for the prevention of epilepsy the molecular mechanism of epileptic activities should be clarified. In the present study the goal is to obtain information for molecular mechanism of epilepsy. To achieve this, molecular alterations from pentylenetetrazol (PTZ)-induced epileptic activities on rat brain tissue and cell memb...
DynaDom: structure-based prediction of T cell receptor inter-domain and T cell receptor-peptide-MHC (class I) association angles
Hoffmann, Thomas; Marıon, Antoıne; Antes, Iris (Springer Science and Business Media LLC, 2017-02-02)
Background: T cell receptor (TCR) molecules are involved in the adaptive immune response as they distinguish between self- and foreign-peptides, presented in major histocompatibility complex molecules (pMHC). Former studies showed that the association angles of the TCR variable domains (Va/V beta) can differ significantly and change upon binding to the pMHC complex. These changes can be described as a rotation of the domains around a general Center of Rotation, characterized by the interaction of two highly...
Citation Formats
H. Boyar, “Biophysical investigation of the effects of antioxidants on normal and diabetic rat bone tissues at molecular level,” Ph.D. - Doctoral Program, Middle East Technical University, 2004.