Investigation of biochemical composition of adrenal gland tumors by means of FTIR.

The application of Fourier transform infrared (FTIR) microspectroscopy for the analysis of biomolecular composition of adrenal gland tumors is described. Samples were taken intraoperatively from three types of adrenal lesions: adrenal adenoma (ACA), adrenal cortical hyperplasia (ACH), both derived from adrenal cortical cells, and pheochromocytoma (Ph) derived from chromaffin cells of the adrenal medulla. The specimens were cryo-sectioned and freeze-dried. Since the investigated lesions originated from different cell types, it was predictable that they might differ in biomolecular composition. The experimental results were used to determine which absorption bands differentiate the analyzed samples the most. The main difference was observed in the lipid functional groups. The experimental results indicated that the level of lipids was higher in both the adenoma and the hyperplasia samples compared to pheochromocytomas. In contrast, the level of proteins was higher in the pheochromocytomas. Furthermore, differences within the range of nucleic acids and carbohydrates were observed in the studied adrenal gland tumor types.

Biomolecular characterization of adrenal gland tumors by means of SR-FTIR.

The adrenal glands are small endocrine organs located on the bottom pole of each kidney. Anatomically they are composed of cortical and medullar parts. Due to dysfunctional processes they can transform into the pathological lesions (in both cortex and medulla). The incidentally detected adrenal lesions have become an arising clinical problem nowadays. The crucial issue for an accurate treatment strategy is relevant diagnosis. Distinguishing between benign and malignant lesions is often difficult during the standard histological examination. Hence the alternative methods of differentiation are investigated. One of them is Fourier transform infrared spectroscopy which allows the analysis of the biomolecular composition of the studied tissue. In this paper we present the very preliminary FTIR studies for defining the biomolecular pattern of three types of adrenal lesions: adenoma (AA) and adrenal cortical hyperplasia (ACH) - both derived from adrenal cortex as well as pheochromocytoma (PCC) - from the medullar part of the gland. All studied cases were classified as benign lesions. The general observations show that cortically derived tissues are rich in lipids and they are rather protein depleted while for medullar pheochromocytoma there is the opposite relationship. Furthermore, the unequivocal differences were noticed within the "fingerprinting" range. In addition subtle shifts in absorption band positions were observed between studied cases.

Synchrotron FTIR micro-spectroscopy study of the rat hippocampal formation after pilocarpine-evoked seizures.

In the present work, synchrotron radiation Fourier transform infrared (SRFTIR) micro-spectroscopy and imaging were used for topographic and semi-quantitative biochemical analysis of rat brain tissue in cases of pilocarpine-induced epilepsy. The tissue samples were analyzed with a beam defined by small apertures and spatial resolution steps of 10 microm which allowed us to probe the selected cellular layers of hippocampal formation. Raster scanning of the samples has generated 2D chemical cartographies revealing the distribution of proteins, lipids and nucleic acids. Spectral analysis has shown changes in the saturation level of phospholipids and relative secondary structure of proteins. Special interest was put in the analysis of two areas of the hippocampal formation (sector 3 of the Ammon's horn, CA3 and dentate gyrus, DG) in which elemental abnormalities were observed during our previous studies. Statistically significant increase in the saturation level of phospholipids (increased ratio of the absorption intensities at around 2921 and 2958 cm(-1)) as well as conformational changes of proteins (beta-type structure discrepancies as shown by the increased ratio of the absorbance intensities at around 1631 and 1657 cm(-1) as well as the ratio of the absorbance at 1548 and 1657 cm(-1)) were detected in pyramidal cells of CA3 area as well as in the multiform and molecular layers of DG. The findings presented here suggest that abnormalities in the protein secondary structure and increases in the level of phospholipid saturation could be involved in mechanisms of neurodegenerative changes following the oxidative stress evoked in brain areas affected by pilocarpine-induced seizures.