Glioblastoma multiforme influence on the elemental homeostasis of the distant organs: the results of inter-comparison study carried out with TXRF method.

Glioblastoma (GBM) is a fast-growing and aggressive brain tumor which invades the nearby brain tissue but generally does not spread to the distant organs. Nonetheless, if untreated, GBM can result in patient death in time even less than few months from the diagnosis. The influence of the tumor progress on organs other than brain is obvious but still not well described. Therefore, we examined the elemental abnormalities appearing in selected body organs (kidney, heart, spleen, lung) in two rat models of GBM. The animals used for the study were subjected to the implantation of human GBM cell lines (U87MG and T98G) characterized by different levels of invasiveness. The elemental analysis of digested organ samples was carried out using the total reflection X-ray fluorescence (TXRF) method, independently, in three European laboratories utilizing various commercially available TXRF spectrometers. The comparison of the data obtained for animals subjected to T98G and U87MG cells implantation showed a number of elemental anomalies in the examined organs. What is more, the abnormalities were found for rats even if neoplastic tumor did not develop in their brains. The most of alterations for both experimental groups were noted in the spleen and lungs, with the direction of the found element changes in these organs being the opposite. The observed disorders of element homeostasis may result from many processes occurring in the animal body as a result of implantation of cancer cells or the development of GBM, including inflammation, anemia of chronic disease or changes in iron metabolism. Tumor induced changes in organ elemental composition detected in cooperating laboratories were usually in a good agreement. In case of elements with higher atomic numbers (Fe, Cu, Zn and Se), 88% of the results were classified as fully compliant. Some discrepancies between the laboratories were found for lighter elements (P, S, K and Ca). However, also in this case, the obtained results fulfilled the requirements of full (the results from three laboratories were in agreement) or partial agreement (the results from two laboratories were in agreement).

Ketogenic diet influence on the elemental homeostasis of internal organs is gender dependent.

The ketogenic diet (KD) is a low-carbohydrate and high-fat diet that gains increasing popularity in the treatment of numerous diseases, including epilepsy, brain cancers, type 2 diabetes and various metabolic syndromes. Although KD is effective in the treatment of mentioned medical conditions, it is unfortunately not without side effects. The most frequently occurring undesired outcomes of this diet are nutrient deficiencies, the formation of kidney stones, loss of bone mineral density, increased LDL (low-density lipoprotein) cholesterol levels and hormonal disturbances. Both the diet itself and the mentioned adverse effects can influence the elemental composition and homeostasis of internal organs. Therefore, the objective of this study was to determine the elemental abnormalities that appear in the liver, kidney, and spleen of rats subjected to long-term KD treatment. The investigation was conducted separately on males and females to determine if observed changes in the elemental composition of organs are gender-dependent. To measure the concentration of P, S, K, Ca, Fe, Cu, Zn and Se in the tissues the method of the total reflection X-ray fluorescence (TXRF) was utilized. The obtained results revealed numerous elemental abnormalities in the organs of animals fed a high-fat diet. Only some of them can be explained by the differences in the composition and intake of the ketogenic and standard diets. Furthermore, in many cases, the observed anomalies differed between male and female rats.

Vibrational spectroscopy methods for investigation of the animal models of glioblastoma multiforme.

Glioblastoma multiforme (GBM) is the most common and devastating primary brain tumor among adults. It is highly lethal disease, as only 25% of patients survive longer than 1 year and only 5% more than 5 years from the diagnosis. To search for the new, more effective methods of treatment, the understanding of mechanisms underlying the process of tumorigenesis is needed. The new light on this problem may be shed by the analysis of biochemical anomalies of tissues affected by tumor growth. Therefore, in the present work, we applied the Fourier transform infrared (FTIR) and Raman microspectroscopy to evaluate changes in the distribution and structure of biomolecules appearing in the rat brain as a result of glioblastoma development. In turn, synchrotron X-ray fluorescence microscopy was utilized to determine the elemental anomalies appearing in the nervous tissue. To achieve the assumed goals of the study animal models of GBM were used. The rats were subjected to the intracranial implantation of glioma cells with different degree of invasiveness. For spectroscopic investigation brain slices taken from the area of cancer cells administration were used. The obtained results revealed, among others, the decrease content of lipids and compounds containing carbonyl groups, compositional and structural changes of proteins as well as abnormalities in the distribution of low atomic number elements within the region of tumor.

Influence of measurement mode on the results of glioblastoma multiforme analysis with the FTIR microspectroscopy.

Fourier Transform Infrared (FTIR) microspectroscopy is well known for its effectiveness in spectral and biochemical analyses of various materials. It enables to determine the sample biochemical composition by assigning detected frequencies, characteristic for functional groups of main biological macromolecules. In analysis of tissue sections one of two measurement modes, namely transmission and transflection, is usually applied. The first one has relatively straightforward geometry, hence it is considered to be more precise and accurate. However, IR-transparent media are very fragile and expensive. Transflection does not require expensive substrates, but is more prone to disruptive influence of Mie scattering as well as electric field standing wave effect. The excessive comparison of spectra' characteristics, obtained via both measurement modes, was performed in this paper. By the means of Mann-Whitney non-parametrical U test and PCA, the comparison of results obtained with both modes and assessment of usefulness of IR spectra obtained with transmission and transflection modes to differentiate between healthy and GBM-affected tissue, were performed. The main objective of the presented research is to compare the results of FTIR analysis of unfixed biological samples performed with transflection and transmission mode. In frame of the study we demonstrated the discrepancies between results of biochemical analysis performed based on data obtained with transmission and transflection. Such observation suggests that caution should be taken in drawing conclusions from the results obtained with transflection geometry, as its more prone to disruptive effects. Despite that, IR spectra developed with both modes allowed to distinguish GBM area from healthy tissue, which proves their diagnostic potential. Especially, application of the ME-EMSC correction of spectra before PCA enhances the performance of both methods to distinguish the analysed tissue areas.

Biochemical changes of macrophages and U87MG cells occurring as a result of the exposure to iron oxide nanoparticles detected with the Raman microspectroscopy.

The core size of iron oxide nanoparticles (IONPs) is a crucial factor defining not only their magnetic properties but also toxicological profile and biocompatibility. On the other hand, particular IONPs may induce different biological response depending on the dose, exposure time, but mainly depending on the examined system. New light on this problem may be shed by the information concerning biomolecular anomalies appearing in various cell lines in response to the action of IONPs with different core diameters and this was accomplished in the present study. Using Raman microscopy we studied the abnormalities in the accumulation of proteins, lipids and organic matter within the nucleus, cytoplasm and cellular membrane of macrophages, HEK293T and U87MG cell line occurring as a result of 24-hour long exposure to PEG-coated magnetite IONPs. The examined nanoparticles had 5, 10 and 30 nm cores and were administered in doses 5 and 25 µg Fe/ml. The obtained results showed significant anomalies in biochemical composition of macrophages and the U87MG cells, but not the HEK293T cells, occurring as a result of exposure to all of the examined nanoparticles. However, IONPs with 10 nm core diminished the accumulation of biomolecules in cells only when they were administered at a larger dose. The Raman spectra recorded for the macrophages subjected to 30 nm IONPs and for the U87MG cells exposed to 5 and 10 nm showed the presence of additional bands in the wavenumber range 1700-2400 cm-1, probably resulting from the appearance of Fe adducts within cells. Our results indicate, moreover, that smaller IONPs may be effectively internalized into the U87MG cells, which points at their diagnostic/therapeutic potential in the case of glioblastoma multiforme.

Altered Elemental Distribution in Male Rat Brain Tissue as a Predictor of Glioblastoma Multiforme Growth-Studies Using SR-XRF Microscopy.

Glioblastoma multiforme (GBM) is a particularly malignant primary brain tumor. Despite enormous advances in the surgical treatment of cancer, radio- and chemotherapy, the average survival of patients suffering from this cancer does not usually exceed several months. For obvious ethical reasons, the search and testing of the new drugs and therapies of GBM cannot be carried out on humans, and for this purpose, animal models of the disease are most often used. However, to assess the efficacy and safety of the therapy basing on these models, a deep knowledge of the pathological changes associated with tumor development in the animal brain is necessary. Therefore, as part of our study, the synchrotron radiation-based X-ray fluorescence microscopy was applied for multi-elemental micro-imaging of the rat brain in which glioblastoma develops. Elemental changes occurring in animals after the implantation of two human glioma cell lines as well as the cells taken directly from a patient suffering from GBM were compared. Both the extent and intensity of elemental changes strongly correlated with the regions of glioma growth. The obtained results showed that the observation of elemental anomalies accompanying tumor development within an animal's brain might facilitate our understanding of the pathogenesis and progress of GBM and also determine potential biomarkers of its extension. The tumors appearing in a rat's brain were characterized by an increased accumulation of Fe and Se, whilst the tissue directly surrounding the tumor presented a higher accumulation of Cu. Furthermore, the results of the study allow us to consider Se as a potential elemental marker of GBM progression.

Ketogenic diet impairs neurological development of neonatal rats and affects biochemical composition of maternal brains: evidence of functional recovery in pups.

The ketogenic diet (KD) is a type of diet in which the intake of fats significantly increases at the cost of carbohydrates while maintaining an adequate amount of proteins. This kind of diet has been successfully used in clinical therapies of drug-resistant epilepsy, but there is still insufficient evidence on its safety when used in pregnancy. To assess KD effects on the course of gestation and fetal development, pregnant females were fed with: (i) KD during pregnancy and lactation periods (KD group), (ii) KD during pregnancy replaced with ND from the day 2 postpartum (KDND group) and (iii) normal diet alone (ND group). The body mass, ketone and glucose blood levels, and food intake were monitored. In brains of KD-fed females, FTIR biochemical analyses revealed increased concentrations of lipids and ketone groups containing molecules. In offspring of these females, significant reduction of the body mass and delays in neurological development were detected. However, replacement of KD with ND in these females at the beginning of lactation period led to regainment of the body mass in their pups as early as on the postnatal day 14. Moreover, the vast majority of our neurological tests detected functional recovery up to the normal level. It could be concluded that the ketogenic diet undoubtedly affects the brain of pregnant females and impairs the somatic and neurological development of their offspring. However, early postnatal withdrawal of this diet may initiate compensatory processes and considerable functional restitution of the nervous system based on still unrecognized mechanisms.

Structural changes in the neocortex as correlates of variations in EEG spectra and seizure susceptibility in rat brains with different degrees of dysplasia.

Disturbances of the early stages of neurogenesis lead to irreversible changes in the structure of the mature brain and its functional impairment, including increased excitability, which may be the basis for drug-resistant epilepsy. The range of possible clinical symptoms is as wide as the different stages of disturbed neurogenesis may be. In this study, we used a quadruple model of brain dysplasia by comparing structural and functional disorders in animals whose neurogenesis was disturbed with a single dose of 1 Gy of gamma rays at one of the four stages of neurogenesis, that is, on days 13, 15, 17, or 19 of prenatal development. When reached adulthood, the prenatally irradiated rats received EEG teletransmitter implantation. Thereafter, pilocarpine was administered and significant differences in susceptibility to seizure behavioral symptoms were detected depending on the degree of brain dysplasia. Before, during, and after the seizures significant correlations were found between the density of parvalbumin-immunopositive neurons located in the cerebral cortex and the intensity of behavioral seizure symptoms or increases in the power of particular EEG bands. Neurons expressing calretinin or NPY showed also dysplasia-related increases without, however, correlations with parameters of seizure intensity. The results point to significant roles of parvalbumin-expressing interneurons, and also to expression of NPY-an endogenous anticonvulsant and neuroprotectant reducing susceptibility to seizures and supporting neuronal survival.

The Use of Fourier Transform Infrared Microspectroscopy for the Determination of Biochemical Anomalies of the Hippocampal Formation Characteristic for the Kindling Model of Seizures.

The animal models of seizures and/or epilepsy are widely used to identify the pathomechanisms of the disease as well as to look for and test the new antiseizure therapies. The understanding of the mechanisms of action of new drugs and evaluation of their safety in animals require previous knowledge concerning the biomolecular anomalies characteristic for the particular model. Among different models of seizures, one of the most widely used is the kindling model that was also applied in our study. To examine the influence of multiple transauricular electroshocks on the biochemical composition of rat hippocampal formation, Fourier transform infrared (FT-IR) microspectrosopy was utilized. The chemical mapping of the main absorption bands and their ratios allowed us to detect significant anomalies in both the distribution and structure of main biomolecules for electrically stimulated rats. They included an increased relative content of proteins with ß-sheet conformation (an increased ratio of the absorbance at the wavenumbers of 1635 and 1658 cm-1), a decreased level of cholesterol and/or its esters and compounds containing phosphate groups (a diminished intensity of the massif of 1360-1480 cm-1 and the band at 1240 cm-1), as well as increased accumulation of carbohydrates and the compounds containing carbonyl groups (increased intensity of the bands at 1080 and 1740 cm-1, respectively). The observed biomolecular abnormalities seem to be the consequence of lipid peroxidation promoted by reactive oxygen species as well as the mobilization of glucose that resulted from the increased demand to energy during postelectroshock seizures.

The influence of IONPs core size on their biocompatibility and activity in in vitro cellular models.

Although the key factor affecting the biocompatibility of IONPs is the core size, there is a lack of regular investigation concerning the impact of the parameter on the toxicity of these nanomaterials. Therefore, such studies were carried out in this paper. Their purpose was to compare the influence of PEG-coated-magnetite NPs with the core of 5, 10 and 30 nm on six carefully selected cell lines. The proliferation rate, viability, metabolic activity, migration activity, ROS levels and cytoskeleton architecture of cells have been evaluated for specified incubation periods. These were 24 and 72-h long incubations with IONPs administered in two doses: 5 and 25 µg Fe/ml. A decrease in viability was observed after exposure to the tested NPs for all the analyzed cell lines. This effect was not connected with core diameter but depended on the exposure time to the nanomaterials. IONPs increased not only the proliferation rate of macrophages-being phagocytic cells-but also, under certain conditions stimulated tumor cell divisions. Most likely, the increase in proliferation rate of macrophages contributed to the changes in the architecture of their cytoskeleton. The growth in the level of ROS in cells had been induced mainly by the smallest NPs. This effect was observed for HEK293T cells and two cancerous lines: U87MG (at both doses tested) and T98G (only for the higher dose). This requires further study concerning both potential toxicity of such IONPs to the kidneys and assessing their therapeutic potential in the treatment of glioblastoma multiforme.

The methods of vibrational microspectroscopy reveals long-term biochemical anomalies within the region of mechanical injury within the rat brain.

Traumatic brain injury (TBI), meaning functional or structural brain damage which appear as a result of the application of the external physical force, constitutes the main cause of death and disability of individuals and a great socioeconomic problem. To search for the new therapeutic strategies for TBI, better knowledge about posttraumatic pathological changes occurring in the brain is necessary. Therefore in the present paper the Fourier transform infrared microspectroscopy and Raman microscopy were used to examine local and remote biochemical changes occurring in the rat brain as a result of focal cortex injury. The site of the injury and the dorsal part of the hippocampal formation together with the above situated cortex and white matter were the subject of the study. The topographic and quantitative biochemical analysis followed with the statistical study using principal component analysis showed significant biomolecular anomalies within the lesion site but not in the area of the dorsal hippocampal formation and in the above situated white matter and cortex. The observed intralesional anomalies included significantly decreased accumulation of lipids and their structural changes within the place of injury. Also the levels of compounds containing phosphate and carbonyl groups were lower within the lesion site comparing to the surrounding cortex. The opposite relation was, in turn, found for the bands characteristic to proteins and cholesterol/cholesterol esters.

The assessment of the usability of selected instrumental techniques for the elemental analysis of biomedical samples.

The fundamental role of major, minor and trace elements in different physiological and pathological processes occurring in living organism makes that elemental analysis of biomedical samples becomes more and more popular issue. The most often used tools for analysis of the elemental composition of biological samples include Flame and Graphite Furnace Atomic Absorption Spectroscopy (F-AAS and GF-AAS), Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Each of these techniques has many advantages and limitations that should be considered in the first stage of planning the measurement procedure. Their reliability can be checked in the validation process and the precision, trueness and detection limits of elements belong to the most frequently determined validation parameters. The main purpose of this paper was the discussion of selected instrumental techniques (F-AAS, GF-AAS, ICP-OES and ICP-MS) in term of the achieved validation parameters and the usefulness in the analysis of biological samples. The focus in the detailed literature studies was also put on the methods of preparation of the biomedical samples. What is more based on the own data the usefulness of the total reflection X-ray fluorescence spectroscopy for the elemental analysis of animal tissues was examined. The detection limits of elements, precision and trueness for the technique were determined and compared with the literature data concerning other of the discussed techniques of elemental analysis. Reassuming, the following paper is to serve as a guide and comprehensive source of information concerning the validation parameters achievable in different instrumental techniques used for the elemental analysis of biomedical samples.

Comparison of Elemental Anomalies Following Implantation of Different Cell Lines of Glioblastoma Multiforme in the Rat Brain: A Total Reflection X-ray Fluorescence Spectroscopy Study.

Glioblastoma multiforme (GBM) is a primary brain tumor with a very high degree of malignancy and is classified by WHO as a glioma IV. At present, the treatment of patients suffering from GBM is based on surgical resection of the tumor with maximal protection of surrounding tissues followed by radio- and pharmacological therapy using temozolomide as the most frequently recommended drug. This strategy, however, does not guarantee success and has devastating consequences. Testing of new substances or therapies having potential in the treatment of GBM as well as detection of their side effects cannot be done on humans. Animal models of the disease are usually used for these purposes, and one possibility is the implantation of human tumor cells into rodent brains. Such a solution was used in the present study the purpose of which was comparison of elemental anomalies appearing in the brain as a result of implantation of different glioblastoma cell lines. These were two commercially available cell lines (U87MG and T98G), as well as tumor cells taken directly from a patient diagnosed with GBM. Using total reflection X-ray fluorescence we determined the contents of P, S, K, Ca, Fe, Cu, Zn, and Se in implanted-left and intact-right brain hemispheres. The number of elemental anomalies registered for both hemispheres was positively correlated with the invasiveness of GBM cells and was the highest for animals subjected to U87MG cell implantation, which presented significant decrease of P, K, and Cu levels and an increase of Se concentration within the left hemisphere. The abnormality common for all three groups of animals subjected to glioma cell implantation was increased Fe level in the brain, which may result from higher blood supply or the presence of hemorrhaging regions. In the case of the intact hemisphere, elevated Fe concentration may also indicate higher neuronal activity caused by taking over some functions of the left hemisphere impaired as a result of tumor growth.

Intravenously administered d-mannitol-coated maghemite nanoparticles cause elemental anomalies in selected rat organs.

In this study novel d-mannitol coated maghemite nanoparticles (MIONPs) are presented in terms of their influence on elemental homeostasis of living organisms and for this purpose highly sensitive total reflection X-ray fluorescence was used. Because of the biological indifference of d-mannitol and presumed lower toxicity of maghemite, compared to the most commonly used magnetite in nanomedicine, such nanoparticles seem to be promising candidates for biomedical applications. The examined dose of MIONPs was comparable with one of the lowest doses used in medical diagnostics. However, it should be emphasized that the amount of iron injected in this form is still significant compared to its total content in organs, especially in kidneys or the heart, and may easily disrupt their elemental homeostasis. The aim of the present study was to evaluate the elemental changes occurring in selected rat organs after injecting a low dose of MIONPs. The results were compared with those obtained for previously examined PEG-coated nanoparticles with magnetite cores. In the light of our findings the elemental changes observed after exposure to MIONPs were less extensive than those following PEG-coated magnetite nanoparticle administration.

Comparison of ultrasmall IONPs and Fe salts biocompatibility and activity in multi-cellular in vitro models.

In the paper, the results of the first regular studies of ultra-small iron oxide nanoparticles (IONPs) toxicity in vitro were presented. The influence of PEG-coated NPs with 5 nm magnetite core on six different cell lines was examined. These were: human bronchial fibroblasts, human embryonic kidney cells (HEK293T), two glioblastoma multiforme (GBM) cell lines as well as GBM cells isolated from a brain tumor of patient. Additionally, mouse macrophages were included in the study. The influence of IONPs in three different doses (1, 5 and 25 µg Fe/ml) on the viability, proliferation and migration activity of cells was assessed. Moreover, quantifying the intracellular ROS production, we determined the level of oxidative stress in cells exposed to IONPs. In the paper, for the first time, the effect of Fe in the form of IONPs was compared with the analogical data obtained for iron salts solutions containing the same amount of Fe, on the similar oxidation state. Our results clearly showed that the influence of iron on the living cells strongly depends not only on the used cell line, dose and exposure time but also on the form in which this element was administered to the culture. Notably, nanoparticles can stimulate the proliferation of some cell lines, including glioblastoma multiforme. Compared to Fe salts, they have a stronger negative impact on the viability of the cells tested. Ultra-small NPs, also, more often positively affect cell motility which seem to differ them from the NPs with larger core diameters.

Efficient generation of neural-like cells from porcine ovarian putative stem cells - morphological characterization and evaluation of their electrophysiological properties.

Until recently, the mammalian ovary was considered to consist of fully differentiated tissues, but evidence for the presence of adult stem cells in this organ appeared. The differentiation potential of these cells, referred to as putative stem cells, is not well defined. Porcine ovarian putative stem cells (poPSCs) were immunomagnetically isolated from postnatal pig ovaries based on the presence of the SSEA-4 surface marker protein. First, they were cultured in the undifferentiated state. After the third passage, a novel 7-day culture method inducing their differentiation into neural-like cells by the addition of forskolin (FSK), retinoic acid (RA) and basic fibroblast growth factor (bFGF) to the culture medium was applied. After 7 days, poPSCs successfully differentiated into neural-like cells, as evidenced by neural morphology and the presence of the neuronal markers nestin, NeuN, and GFAP, as confirmed by immunofluorescence, western blot, and real-time PCR. Electrophysiological analysis of potassium and sodium channel activity (patch clamp) confirmed that they indeed differentiated into neurons. The plasticity of poPSCs offers an excellent opportunity, especially in the field of neuroscience, since they can differentiate into neurons or glial cells. Although poPSCs might not be pluripotent cells, they also escape the rigid classification framework of adult stem cells.

MRI spectroscopic and tractography studies indicate consequences of long-term ketogenic diet.

To maintain its functional abilities, the mature brain obtains energy from glucose produced in carbohydrate metabolism. When carbohydrates are eliminated from the diet, the energy comes from the oxidation of fatty acids. In this metabolic state called ketosis, ketone bodies are formed: ß-hydroxybutyric acid (bHb), acetone, and acetoacetate as alternative source of energy passing through the blood-brain barrier easily. The ketosis state can be achieved through various strategies like caloric restriction, supplementation with medium-chain triglycerides, intense physical training, or ketogenic diet (KD). Using KD, drug-resistant epilepsy has been successfully treated in children and adults. It can also exert neuroprotective influences in cases of brain damage, glioblastoma multiforme, and Alzheimer's or Parkinson's diseases. Although many possible mechanisms of KD activity have been proposed, newer hypotheses appear with the research progress, mostly characterizing the brain under pathological but not normal conditions. Since different pathological conditions may affect the mechanism of KD action differently, additional research on the normal brain appears reasonable. For this purpose, young adult rats were treated with 4-month-lasting KD. Then, MRI structural measurements, spectroscopy, and tractography were performed. The procedures revealed significant increases in the concentration of glutamine, glutamate, glutathione and NAA, accompanied by changes in the pattern of neuronal connections of the striatum and hippocampal formation. This implies a possible involvement of these structures in the functional changes occurring in the brain after KD application. Thus, the investigations on the normal brain add important details concerning mechanisms underlying KD effects without their possible modification by a pathological status.

Changes of EEG spectra in rat brains with different patterns of dysplasia in response to pilocarpine-induced seizures.

Disorders of neurogenesis at early developmental stages lead to irreversible structural and functional impairments of the brain. As further their consequences, increases in brain excitability and the development of drug-resistant epilepsy can frequently be observed in clinical cases. Mechanisms underlying these phenomena can also be examined on animal models of brain dysplasia. This study was conducted on rats with four degrees of brain dysplasia following exposure to gamma radiation on days 13, 15, 17, or 19 of prenatal development. When reached adulthood, the rats received electroencephalographic (EEG) transmitter implantation. Thereafter, pilocarpine was administered, and significant differences in susceptibility to seizures were detected depending on the degree of brain dysplasia. Before, during, and after the seizures, EEG was recorded in free moving animals. Additionally, the intensity of seizure behavioral symptoms was assessed. Strong and moderate correlations were found between the intensity of seizure behavioral symptoms, the power of particular EEG bands, and volumes of dysplastic brains and their regions. The data drew particular attention to correlations between variations in EEG spectra and changes in the midbrain and pons volumes. The results point to possible significant roles of these regions in the observed changes of susceptibility to seizures. Consequently, the frequently used experimental model was considered here not only as representing cases of cortical dysplasia but also of generalized, diffuse dysplasia of the whole brain.

FTIR microspectroscopy revealed biochemical changes in liver and kidneys as a result of exposure to low dose of iron oxide nanoparticles.

Iron oxide nanoparticles (IONPs) have biomedical and biotechnological applications in magnetic imaging, drug-delivery, magnetic separation and purification. The biocompatibility of such particles may be improved by covering them with coating. In presented paper the biochemical anomalies of liver and kidney occurring in animals exposed to d-mannitol-coated iron(III) oxide nanoparticles (M-IONPs) were examined with Fourier transform infrared (FTIR) microspectroscopy. The dose of IONPs used in the study was significantly lower than those used so far in other research. Liver and kidney tissue sections were analysed by chemical mapping of infrared absorption bands originating from proteins, lipids, compounds containing phosphate groups, cholesterol and cholesterol esters. Changes in content and/or structure of the selected biomolecules were evaluated by comparison of the results obtained for animals treated with M-IONPs with those from control group. Biochemical analysis of liver samples demonstrated a few M-IONPs induced anomalies in the organ, mostly concerning the relative content of the selected compounds. The biomolecular changes, following exposition to nanoparticles, were much more intense within the kidney tissue. Biochemical aberrations found in the organ samples indicated at increase of tissue density, anomalies in fatty acids structure as well as changes in relative content of lipids and proteins. The simultaneous accumulation of lipids, phosphate groups as well as cholesterol and cholesterol esters in kidneys of rats exposed to IONPs may indicate that the particles stimulated formation of lipid droplets within the organ.