Involvement of α-, γ- and δ-Tocopherol Isomers fromPumpkin (Cucurbita pepo L.) Seed Oil or Oil Mixtures inthe Biphasic DPPH˙ Disappearance Kinetics.

The antioxidant activity of three types of pumpkin seed oil or oil mixtures (cold- -pressed, produced from roasted seed paste and salad) produced in the northern part of Croatia and the kinetics of their behaviour as free radical scavengers were investigated using DPPH˙. In addition, the involvement of oil tocopherol isomers (α-, γ- and δ-) in different steps of DPPH˙ disappearance and their impact on the rate of reaction were analysed. The kinetics of DPPH˙ disappearance is a two-step process. In the first step, rapid disappearance of DPPH˙ occurs during the first 11 min of the reaction, depending on the oil type, followed by a slower decline in the second step. To describe DPPH˙ disappearance kinetics, six mathematical models (mono- and biphasic) were tested. Our findings showed that γ- and δ-tocopherols affected DPPH˙ disappearance during the first step, and α-tocopherol in the second step of the reaction. Moreover, α-tocopherol demonstrated 30 times higher antioxidant activity than γ- and δ-tocopherols. The results indicated the biphasic double-exponential behaviour of DPPH˙ disappearance in oil samples, due to the complexity of reactions that involve different tocopherol isomers and proceed through different chemical pathways.

Influence of cadmium on metallothionein expression and products of lipid peroxidation in the organs of hares (Lepus europaeus Pallas).

Cadmium occurs naturally in the environment and as an anthropogenic pollutant. Exposure to low concentrations of cadmium is inevitable and may produce toxic effects. Another important aspect of cadmium toxicity is its interaction, often antagonistic, with essential elements such as selenium. The aim of this study was to highlight the risks of long-term exposure to low cadmium concentrations, using a scientific and chemical approach and hares (Lepus europaeus Pallas) as model organisms in a field study. Two study areas were monitored. Levels of cadmium and selenium were quantified in the organs of hares, the expression of metallothioneins I + II and the products of lipid peroxidation were determined. The median cadmium concentrations (wet weight) in the muscle, liver, kidney and brain of hares from an exposed group ranged from 0.033 to 0.037, 0.763 to 1.054, 3.090 to 16.594 and 0.016 to 0.087 µg g(-1), respectively; whereas, the median selenium concentrations (wet weight) ranged from 0.100 to 0.108, 0.153 to 0.332, 0.677 to 0.701 and 0.078 to 0.116 µg g(-1), respectively. Expression of the metallothioneins I + II proteins was observed in tissues. Lipid peroxidation (LPO) levels, measured as malondialdehyde (MDA) equivalents, increased with the cadmium concentration. Further research on long-term exposure to low concentrations of cadmium in the environment is needed.

Metallothioneins I/II expression in rat strains with genetically different susceptibility to experimental autoimmune encephalomyelitis.

OBJECTIVES: Compared to the Dark Agouti (DA), the Albino Oxford (AO) rat strain exhibits lower susceptibility to the induction of experimental autoimmune encephalomyelitis (EAE). Here, we investigated the potential contribution of the heavy metal-binding proteins metallothioneins (MTs) I/II to these effects. METHODS: Rats were immunized with bovine brain homogenate emulsified in complete Freund's adjuvant or only with complete Freund's adjuvant. The expression patterns of MTs mRNA and proteins and tissue concentrations of Zn2+ and Cu2+ were estimated in the brain and in the liver on days 7 and 12 after immunization, by real-time PCR, immunohistochemistry and inductively coupled plasma spectrometry, respectively. Additionally, the hepatic transforming growth factor beta and nuclear factor kappa B immunoreactivities were tested. RESULTS: Clinical signs of EAE were not induced in AO rats, but they upregulated the expression of MT I/II proteins in the brain (hippocampus and cerebellum) and in the liver, similarly as DA rats. The transcriptional activation of MT-I occurred, however, only in DA rats, which accumulated also more zinc in the brain and in the liver. In contrast, intact AO rats had greater hepatic MT-I mRNA immunoreactivity and more Cu2+ in the hippocampus. Besides, in immunized AO rats a high upregulation of transforming growth factor beta and nuclear factor kappa B immunoreactivities was found in several hepatic structures (vascular endothelium, Kupffer cells and hepatocytes). CONCLUSIONS: Our data show that AO and DA rats differ in constitutive and inductive MT-I gene expression in the brain and in the liver, as well as in the hepatic cytokine profile, suggesting that these mechanisms may contribute to the discrepancy in the susceptibility to EAE.

Hepatic expression of metallothionein I/II, glycoprotein 96, IL-6, and TGF- ß in rat strains with different susceptibilities to experimental autoimmune encephalomyelitis.

In a search of peripheral factors that could be responsible for the discrepancy in susceptibility to EAE in Albino Oxford (AO) and Dark Agouti (DA) rats, we estimated the expression of metallothioneins I/II (MT), heat shock protein-gp96, interleukin (IL)-6, and transforming growth factor (TGF)- ß in the livers of these animals. Rats were immunized with bovine brain homogenate (BBH) emulsified in complete Freund adjuvant (CFA) or only with CFA. Western blot and immunohistochemical analyses were done on day 12 after the immunization, as well as in intact rats. The data have shown that during the first attack of EAE only the EAE prone-DA rats markedly upregulated the hepatic MTs, gp96, IL-6, and TGF- ß . In contrast, AO rats had a significantly higher expression of MT I/II, IL-6, and TGF- ß in intact liver (P < 0,001), suggesting that the greater constitutive expression of these proteins contributed to the resistance of EAE. Besides, since previously we found that AO rats reacted on immunization by an early upregulation of TGF- ß on several hepatic structures (vascular endothelium, Kupffer cells, and hepatocytes), the data suggest that the specific hepatic microenvironment might contribute also to the faster recovery of these rats from EAE.

Effects of mercury on glutathione and glutathione-dependent enzymes in hares (Lepus europaeus Pallas).

The aim of this study was to analyze and evaluate risks of long-term exposure to mercury in hares (Lepus europaeus Pallas), with a chemical-analytical approach evaluating median mass fraction of toxic mercury in the hares organs (liver, kidney, muscle and brain). To obtain better insight into possible effects of mercury, the study included screening of the oxidative status after long term exposure to low concentrations of mercury. Hares organs were analyzed for total mercury concentration by AAS. Glutathione and glutathione-dependent enzymes status was also investigated. The median mercury concentrations (wet weight) in the liver, kidney, muscle and brain of the hares ranged from 0.058-0.189, 0.138-0.406, 0.013-0.046 and 0.022-0.102 µg/g respectively. Concentration of the glutathione (GSH), glutathione-peroxidase (GPx), and glutathione-reductase (GR) activity increased with the mercury concentration. However, glutathione S-transferase (GST) and superoxide-dismutase (SOD) activity decreased with the mercury concentration. The results of this study show the impact of environmentally absorbed mercury on the antioxidant status of the examined hares. Further research on long-term exposure to low concentrations of mercury is needed.

Mathematical prediction of imidacloprid persistence in two Croatian soils with different texture, organic matter content and acidity under laboratory conditions.

In the present laboratory study, persistence of imidacloprid (IMI) as a function of initial insecticide concentration and soil properties in two Croatian soils (Krk sandy clay and Istria clay soils) was studied and described mathematically. Upon fitting the obtained experimental data for the higher concentration level (5 mg/kg) to mathematical models, statistical parameters (R (2), scaled root mean squared error and χ (2) error) indicated that the single first-order kinetics model provided the best prediction of IMI degradation in the Krk sandy clay soil, while in the Istria clay soil biphasic degradation was observed. At the lower concentration level (0.5 mg/kg), the biphasic models Gustafson and Holden models as well as the first-order double exponential model fitted the best experimental data in both soils. The disappearance time (DT50) values estimated by the single first-order double exponential model (from 50 to 132 days) proved that IMI can be categorized as a moderately persistent pesticide. In the Krk sandy clay soil, resulting DT50 values tended to increase with an increase of initial IMI concentration, while in the Istria clay soil, IMI persistence did not depend on the concentration. Organic matter of both experimental soils provided an accelerating effect on the degradation rate. The logistic model demonstrated that the effect of microbial activity was not the most important parameter for the biodegradation of IMI in the Istria clay soil, where IMI degradation could be dominated by chemical processes, such as chemical hydrolysis. The results pointed that mathematical modeling could be considered as the most convenient tool for predicting IMI persistence and contributes to the establishment of adequate monitoring of IMI residues in contaminated soil. Furthermore, IMI usage should be strictly controlled, especially in soils with low organic matter content where the risk of soil and groundwater contamination is much higher due to its longer persistence and consequent leaching and/or moving from soil surface prior to its degradation.

Effects of temperature on sorption-desorption processes of imidacloprid in soils of Croatian coastal regions.

Sorption-desorption behavior of imidacloprid in six soils collected from five coastal regions in Croatia at 20, 30 and 40°C was investigated using batch equilibrium technique. Isothermal data were applied to Freundlich, Langmuir and Temkin equations, and the thermodynamic parameters ΔH°, ΔG°, ΔS° were calculated. The sorption isotherm curves were non-linear and may be classified as L-type, suggesting a relatively high sorption capacity for imidacloprid. Our results showed that the K( sor ) ( F ) values decreased for all the tested soils as the temperature increased, indicating that the temperature strongly influences the sorption. Values of ΔG° were negative (-4.65 to -2.00 kJ/mol) indicating that at all experimental temperatures the interactions of imidacloprid with soils were spontaneous processes. The negative and small ΔH° values (-19.79 to -8.89 kJ/mol) were in the range of weak forces, such as H-bonds, consistent with interactions and partitioning of the imidacloprid molecules into soil organic matter. The ΔS° values followed the range of -57.12 to -14.51 J/molK, suggesting that imidacloprid molecules lose entropy during transition from the solution phase to soil surface. It was found that imidacloprid desorption from soil was concentration and temperature-dependent, i.e. at lower imidacloprid concentrations and temperature, lower desorption percentage occurred. Desorption studies revealed that hysteretic behavior under different temperature treatments existed, and it was more pronounced at 20°C in the soils with higher OC content. The study results emphasize the importance of thermodynamic parameters in controlling soil pesticide mobility in different geographical locations, seasons and greenhouse conditions.

Effect of olive oil on brain's lipid and calcium content after partial hepatectomy in mice.

The aim of this study was to investigate the influence of olive oil (00) enriched diet on the lipid content of mice brain during the early phase of liver regeneration and to test a relationship of these changes with calcium content. C57BI mice were fed over 21 days with diet enriched with olive oil, containing predominantly oleic acid (18:1n-9). The animals were one-third partially hepatectomised (pHx) under aether anaesthesia. Total lipids were extracted from tissue samples with a chloroform-methanol (2:1, v/v) mixture according to Folch et al. Mineral concentration was determined by inductively coupled plasma atomic emission spectroscopy (ICP-AES) after microwave brain tissue digestion. The diet containing 00 increased both total lipid content and the calcium concentration in brain during the early phase of liver regeneration (12hrs post pHx), suggesting that monounsaturated oleic acid might interact with some metal-dependent activities that control changes in the brain during liver regeneration.

Characterisation of Monovarietal Olive Oils Obtained from Croatian cvs. Drobnica and Buza during the Ripening Period.

The aim of this study was the monitoring of the chemical composition of olive oil at different ripening stages to determine the appropriate harvesting time during any given crop season in the northern Adriatic region. For this purpose, from September to November, two Croatian olive cultivars (Drobnica and Buza) were taken from two different olive orchards and for the respective olive oils, prepared on a laboratory scale, the major saponifiable, unsaponifiable and phenolic compounds were determined. Based on the chemical analyses performed, the optimal harvesting time has been set in October for both cultivars. Buza had a higher oleic acid, but lower total sterols, squalene and total alkanols. Compared to the local cultivars, the studied cultivars had a high total phenolic content and antioxidant activity. The antioxidant activity and concentrations of total phenols correlated with α-tocopherol in oil samples taken during the ripening progress. Finally, trace minerals detected in Buza and Drobnica oil differed, which can be an indicator of oxidative stability and authenticity of oils.

Oxidative stress in mice: effects of dietary corn oil and iron.

The aim of this study was to analyze the effect of high dietary Fe on liver antioxidant status in mice fed a corn-oil-enriched diet. Male Balb/c mice were fed for 3 wk with a standard diet enriched with 5% by weight of corn oil with adequate Fe (FCO diet) or supplemented with 1% carbonyl Fe (FCOFe diet). The control group was fed a standard diet. The high-Fe diet induced a twofold increase of hepatic Fe level. However, an increase of thymic Fe level has been induced solely by dietary fat. The hepatic copper (Cu) level slightly decreased in the FCO diet. In the spleen, the high-Fe diet-induced increase of Fe level was negatively correlated with the Cu level. The antioxidant status was influenced by both dietary fat and Fe. Mice fed corn-oil-enriched diets had a higher concentration of thiobarbituric acid-reactive substances (TBARS), with a greater increase in the FCOFe diet. Fatty acid analysis showed decreased n-3 and n-6/n-3 ratio, particularly in the FCOFe diet. Hepatic Cu/Zn superoxide dismutase (CuZn-SOD) activity was decreased in FCO diet, and Fe supplementation caused a further decrease in the enzyme activity. These results suggest that feeding with corn oil-enriched diet increases oxidative damage by decreasing antioxidant enzyme defense. The high-Fe diet additionally affects the antioxidant defense system, further increasing the tissue's susceptibility to lipid peroxidation. Additionally, both corn-oil- and Fe-enriched diets have increased the Cu requirement in mice.

Liver fatty acid and element changes after partial hepatectomy in mice fed olive oil- and corn oil-enriched diets.

The purpose of this study was to explore the effect of dietary fats on the hepatic fatty acid profile of mice liver after partial hepatectomy and to observe a correlation with changes in element content. Male Balb/C mice were divided into three groups: the control animals fed a standard diet (FSD), the FOO group fed a diet enriched with 5% olive oil, and the FCO group fed a diet enriched with 5% corn oil. Hepatic fatty acid and element content were analyzed within each group in intact animals and on d 1, 2, and 7 after partial hepatectomy. During the regenerative process, proportions of 18:1n-9 and 18:3n-6 substantially increased in the FSD diet, correlating with the Zn level. On the other hand, 20:4n-6 and 22:6n-3 decreased on d 1 and 2. Consequently, a significant increase in the n-6: n-3 ratio was found in these animals. In the FOO diet, a decreased polyunsaturated fatty acid/monounsaturated fatty acid (PUFA/MUFA) ratio was related to a significant decrease in PUFA content, mainly the result of decreased 20:3n-6 and 20:4n-6. The proportion of 18:1n-9 was highly increased when compared with other diets and remained high during the regeneration. Furthermore, the n-6: n-3 ratio was increased on d 2 and 7. Zn increased on d 1 and 2, and Fe increased on d 2. Feeding with corn oil generally induced an increase in the PUFA n-6 series, compared with other diets. The PUFA n-3 series decreased and the 18:1n-9 increased on d 1, compared to intact animals. Consequently, the n-6: n-3 ratio was elevated during the regeneration. Zn increased on d 1 and 2, whereas Fe remained unchanged until d 7, when it decreased. Decreased 20:4n-6 on d 1 and 2, as well as Cu on d 7, and increased Zn in the first 2 d were common to all three diets. These findings suggest that some significant signals transmitted during the regenerative process have induced alterations in the fatty acid composition and changes in the liver element content, which can be modified by the diet.

Metallothionein expression and tissue metal kinetics after partial hepatectomy in mice.

To better elucidate previous results showing that partial hepatectomy noticeably changes the tissue content of zinc, calcium, magnesium, and iron(II) ions in regenerating the liver, thymus, and spleen, we report on the correlation of these metal tissue kinetics in these organs with the expression of metallothionein-I+II (MT-I+II) proteins and MT-I mRNA in early postoperative period (1, 2, 6, 12, and 24 h) after one-third hepatectomy (pHx). The results showed that 2 h after pHx the regenerating liver accumulated Zn2+, Ca2+, Mg2+, and Fe2+ ions while decreasing the concentration of all these metals in the spleen and of Zn2+ in the thymus. On the 24th h, a new high accumulation of Zn2+ and Ca2+ was seen in the regenerating liver and of Zn2+, Ca2+, and Fe2+ in the spleen. Simultaneously, MT-I mRNA increased in the liver and spleen. In hepatocytes and on several spleen and thymus mononuclear lymphatic cells, the increased expression of MT proteins was found mainly in the cytoplasm and nuclei. The areas expressing MTs in regenerating liver inversely correlated with those containing apoptotic cells, suggesting that these proteins participate in tissue restoration through reduction or increase of metal ions after injury to the liver.

Preexposure to Olive Oil Polyphenols Extract Increases Oxidative Load and Improves Liver Mass Restoration after Hepatectomy in Mice via Stress-Sensitive Genes.

Polyphenols can act as oxidants in some conditions, inducing redox-sensitive genes. We investigated the effect of preexposure to the olive oil polyphenols extract (PFE) on time-dependent changes in the hepatic oxidative state in a model of liver regeneration-a process in which oxidative stress associated with the metabolic overload accounts for the early events that contribute to the onset of liver self-repair. Liver regeneration was induced by one-third hepatectomy in mice. Prior to hepatectomy, mice were intraperitoneally given either PFE (50 mg/kg body weight) or saline for seven consecutive days, while respective controls received vehicle alone. Redox state-regulating enzymes and thiol proteins along with the mRNA levels of Nrf2 gene and its targets γ-glutamylcysteine synthetase and heme oxygenase-1 were determined at different time intervals after hepatectomy. The liver mass restoration was calculated to assess hepatic regeneration. The resulting data demonstrate the effectiveness of preexposure to PFE in stimulating liver regeneration in a model of a small tissue loss which may be ascribed to the transient increase in oxidant load during the first hours after hepatectomy and associated induction of stress response gene-profiles under the control of Nrf2.

Chronic iron overload induces gender-dependent changes in iron homeostasis, lipid peroxidation and clinical course of experimental autoimmune encephalomyelitis.

To analyze iron- and gender-dependent mechanisms possibly involved in pathogenesis of multiple sclerosis (MS) in this study we evaluated the effects of iron overload (IO) on iron status and lipid peroxidation processes (LPO) in tissues of female and male DA rats during chronic relapsing experimental autoimmune encephalomyelitis, a well-established MS animal model. Rats were treated by iron sucrose (75mg/kg bw/day) or with saline solution during two weeks before the sensitization with bovine brain homogenate in complete Freund's adjuvant. Clinical signs of EAE were monitored during 29 days. Serum and tissues of CNS and liver were sampled before immunization and at day 13th post immunization (during acute phase of EAE). The determination of ferritin, iron, malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE) and evaluation of histopathology were performed by ELISA, ICP spectrometry and immunohistochemistry. Results showed that IO in female EAE rats accelerated the onset of disease. In contrast, in male rats it accelerated the progression of disease and increased the mortality rate. During acute phase of EAE female IO rats sequestered more Fe in the liver, spinal cord and in the brain and produced more ferritin than male EAE rats. Male rats, however, reacted on IO by higher production of MDA or 4-HNE in the neural tissues and showed greater signs of plaque formation and gliosis in spinal cord. The data point to sexual dimorphism in mechanisms that regulate peripheral and brain iron homeostasis and imply that men and women during MS might be differentially vulnerable to exogenous iron overload.

Metal tissue kinetics in regenerating liver, thymus, spleen, and submandibular gland after partial hepatectomy in mice.

Liver regeneration after partial hepatectomy (pHx) is a well-defined process, which involves the concerted action of extra- and intracellular factors resulting in induction of cell replication and its inhibition at the time when the entire liver mass is restored. Concomitantly, the breakdown of previously maintained tolerance and the exposure of self-antigens lead to the activation of preimmune and immune repertoires, which participate in surveillance against aberrant cells and the re-establishment of previous morphostasis. Because, in these events, important biological function might have tissue minerals that are affecting the structural integrity and enzyme activities, transduction signals, transcription and replication factors during cell proliferation and apoptosis, as well as the development and maintenance of immune functions and cytokine production, in this study we analyzed tissue dynamics of zinc, iron, magnesium, and calcium in the liver, thymus, spleen, and submandibular gland in intact and pHx mice on the 1st, 2nd, 7th, and 15th d after one-third pHx, using microwave digestion and inductivity coupled plasma spectrometry. The data showed that pHx induces significant and interconnected changes in all of the estimated metals not only in the regenerating liver but also in the lymphatic tissues and submandibular gland, indicating their importance for the control of growth processes.

Accumulated Metals and Metallothionein Expression in Organs of Hares (Lepus europaeus Pallas) Within Natural Gas Fields of Podravina, Croatia.

Environmental impact of natural gas facility near Molve (Podravina, Croatia) was assessed using hares (Lepus europaeus Pallas) as biomonitors. Elevated levels of heavy metals in the environment lead to their accumulation in different tissues of hares. The authors have tested accumulation and distribution of several metals in hare liver, kidney, and muscle tissues. The accumulation of copper in hare liver and kidneys with concomitant decrease of zinc was observed in animals from Podravina region as opposed to the control group of animals (Island Krk, Croatia). Secondly, the expression of metallothioneins was assessed because of their crucial role in metal homeostasis. Observed elevation of metallothionein expression in tested organs emphasizes the possible prolonged negative effects of heavy metals in the surroundings as well as a state of oxidative stress in animals. Further monitoring of the area is necessary for better control of hydrocarbon processing to diminish the possible negative environmental effects.

Gas chromatographic determination of fatty acids contained in different lipid classes after their separation by solid-phase extraction.

A quick and successful procedure is presented for the separation of polar lipids, monoacylglycerols (MAGs), diacylglycerols and triacylglycerols (TAGs) and for fatty acid determination in the above-mentioned lipid fractions by gas chromatographic analysis, which was acceptable for physiological and nutrition studies. In the analysis of edible oils and biological tissue samples, lipid classes were separated and purified by solid-phase extraction (SPE) using an aminopropylsilica column. Fatty acids in the sn-2 position in edible oil TAGs were determined after previous 1,3-specific lipase hydrolysis and separation of 2-MAGs by SPE using an aminopropylsilica column. A preliminary study of the solid-phase extraction separation of lipid classes with stock standard solutions using styrene-divinylbenzene-methacrylate copolymer (Nexus), octadecylsilica (C18) and aminopropylsilica (NH2) was carried out and it was shown that NH2 was the best sorbent for the above-mentioned purpose.

Metallothioneins and trace elements dyshomeostasis induced by exposure to gasoline vapor in mice.

To investigate the effects of air pollution related with the gasoline/petrochemical industry the expression of metallothionein I (MT-I) mRNA and tissue metals were analyzed in organs of mice, exposed to gasoline (G) vapor in laboratory conditions. Control groups consisted of intact mice and of those exposed in the metabolic chamber to fresh air. The data obtained by RT-PCR and inductively coupled plasma spectrometry have shown that exposure to G vapor leads to upregulation of MT-I mRNA in organs that receive a strong respiratory and olfactory input or participate in gasoline degradation and elimination (lungs, brain, kidney and liver). Besides, in the brain and in the lungs, kidney and liver a decreased tissue content of Zn²âº or Cu²âº and Mg²âº was found (p<0.001). Some of these changes were obtained also in mice closed in the metabolic chamber, pointing to the involvement of stress-induced mechanisms in the transcriptional regulation of MTs.

Metallothionein I+II expression as an early sign of chronic relapsing experimental autoimmune encephalomyelitis in rats.

Metallothioneins (MTs) are small, cysteine-rich proteins which have been implicated in various forms of stress providing cytoprotective action against oxidative injury, DNA damage and apoptosis. Owing to their high affinity for physiological metals, such as zinc and copper MTs are also critical components of regulatory proteins involved in cell growth and multiplication, as well as in the maintenance of immune homeostasis. To elucidate the role of MTs in the pathomechanisms of autoimmune CNS disorders we estimated the expression of MT I+II proteins and the content of free Zn ions in the brain, spinal cord and in the liver early in the course of chronic relapsing experimental autoimmune encephalomyelitis (CR-EAE) pathogenesis, i.e. before the onset of any clinical symptoms. Disease was induced in the genetically susceptible Dark Agouti (DA) rats by subcutaneous injection of bovine brain homogenate in CFA. Control animals were treated with CFA alone. The data, obtained by immuno-histochemistry and in situ fluorescent labeling of free zinc ions, have shown that in the presymptomatic phase of CR-EAE (on the seventh postimmunization day) MTs I+II were markedly upregulated in the cells that form blood-brain and blood-cerebrospinal fluid barriers, as well as in the cerebellar parenchyma and hippocampal dentate gyri. Furthermore, we found that the liver also becomes a site of extensive MTs I+II synthesis shortly after immunization. Simultaneously, tissue content of free zinc ions increased at the sites of MTs induction, reflecting their antioxidative activity. The data, described in this paper point to regulatory and neuroprotective role of MTs in the pathogenesis of CR-EAE.

Kinetics of tissue iron in experimental autoimmune encephalomyelitis in rats.

To elucidate the role of iron in the pathomechanisms of autoimmune CNS disorders, we estimated the tissue concentrations of Fe(2+) in the brain, spinal cord, and liver in the chronic relapsing form of experimental autoimmune encephalomyelitis (EAE). The disease was induced in Dark Agouti (DA) strain of rats, by subcutaneous injection of bovine brain homogenate in complete Freund's adjuvant (CFA). Control rats consisted of unsensitized rats and of rats treated with CFA or saline. The data obtained by clinical assessment and by inductively coupled plasma spectrometry have shown that the attacks of disease (on the 12th and 22nd post-immunization day) were followed by high accumulation of iron in the liver. Additionally, during the second attack of disease, the decreased concentration of Fe(2+) was found in cervical spinal cord. The data point to regulatory effects of iron and hepatic trace elements regulating mechanisms in the pathogenesis of EAE.