Differences between antioxidant defense parameters and specific trace element concentrations in healthy, benign, and malignant brain tissues.

There are only a few reports examining the impact of oxidative stress in patients with benign and malignant brain tumors. In this study we investigated whether there are changes in antioxidant system (AOS) parameters and key trace elements between control, benign and malignant brain tissues. The study also aimed to examine correlations between the analyzed parameters. The study enrolled both types of brain tumors, benign tumors (BT) and malignant tumors (MT). The results were compared with control tissue (CT) without tumor infiltration collected from patients with BT. The following antioxidant parameters were determined: activities of total, manganese-containing, and copper/zinc-containing superoxide dismutase (TotSOD, MnSOD and CuZnSOD), activities of catalase, glutathione peroxidase, glutathione S-transferase, glutathione reductase and acetylcholine esterase (AChE), the concentrations of glutathione and sulfhydryl groups and of manganese (Mn), copper (Cu), zinc (Zn), and selenium (Se). BT and MT had altered activities/levels of multiple AOS parameters as compared to CT, indicating that tumor cells had an altered cell metabolism and changes in AOS represent adaptive response to increased oxidative stress. Low MnSOD and AChE and high GST activities were significant for distinguishing between MT and CT. Malignant tissue was also characterized by lower Mn and Cu concentrations relative to CT and BT. Principal Component Analysis clearly discriminated BT from CT and MT (PC1, 66.97%), while PC2 clearly discriminated CT from BT and MT (33.03%). Most correlative relationships were associated with Se in the BT group and Cu in the MT group. The results of this study reveal differences between the AOS parameters and the essential trace elements between the analyzed groups. The observed dysregulations show that oxidative stress could have an important role in disrupting brain homeostasis and its presence in the pathogenesis of benign and malignant brain tumors.

Possible zinc deficiency in the Serbian population: examination of body fluids, whole blood and solid tissues.

Studies indicate that the soil, water and consequently foodstuffs in Serbia are significantly poor in zinc (Zn), and thus, it is likely that there is a Zn deficiency in the Serbian population. This study examined the Zn status in multiple clinical samples, including body fluids (serum, cerebrospinal fluid), whole blood and Zn-rich solid tissues (thyroid and brain tissue). Differences between sex and age were also considered, and comparative analysis of Zn status with other world populations was performed. Serum samples from a large number of Serbian adults approximately had twofold lower Zn amounts when compared to other populations. A similar trend was obtained for whole blood. Males had significantly higher amounts of Zn in serum, whole blood and thyroid tissue samples than females. Higher amounts of Zn were observed in the group older than 50 years. Importantly, in thyroid and brain tissues, Zn was 10- and 20-fold lower, respectively, than reported in the literature. Our results indicate that the population in Serbia could be considered Zn deficient. Therefore, adequate oral Zn supplementation and/or foodstuff fortification should be considered to prevent the deleterious effects caused by Zn deficiency.

Reference values for trace essential elements in the whole blood and serum samples of the adult Serbian population: significance of selenium deficiency.

This study was aimed to determine reference values (RVs) for the manganese (Mn), copper (Cu), zinc (Zn), and selenium (Se) in the whole blood (B) and serum (S) samples of the Serbian population. Blood specimens were collected from healthy persons (n = 295; women/men ratio = 149/146; mean age: 42 ± 2 years). The RVs were calculated as lower limit (LL) and upper limit (UL) of the 95% confidence interval (CI) and were expressed as percentiles (P) in the range from P2.5 to P97.5. The influences of sex, age, and smoking habits on element profiles were considered. It was found that the contents of B-Cu and S-Cu were higher in women, while the contents of B-Zn and S-Zn were higher in men. Both trace elements were significantly increased in a group of persons above 40 when compared to a younger persons (≤ 40 years). According to smoking habits, increased content was found only for S-Mn in the nonsmoker's group (p < 0.05). Comparing our results to the results reported in other population groups worldwide, the Serbian population had significantly reduced content of Se in both types of samples. This finding could highlight the deficiency of Se in the investigated Serbian population and could contribute to the better understanding of the molecular basis for the increased incidence of thyroid and other diseases in which selenium plays a key role.

The human biomonitoring study in Serbia: Background levels for arsenic, cadmium, lead, thorium and uranium in the whole blood of adult Serbian population.

The purpose of this study was to establish reference values (RVs) for the occupationally- and environmentally-important toxic elements in the whole blood of adult Serbian population for the first time. Contaminated drinking water with arsenic, high share of smokers in the country, removing tetraethyl lead from the gasoline and war attack at the end of the twentieth century were some of the reasons to provide background information for arsenic (As), cadmium (Cd), lead (Pb), thorium (Th), and uranium (U) in the blood of the Serbian population. The whole blood samples were collected from the healthy respondents living in the Belgrade and surrounding areas of the capital (n = 305; w/m ratio = 154/151; mean age: 41 ±â€¯2). The concentrations of toxic metals were determined by inductively coupled plasma-mass spectrometry (ICP-MS). Reference values were estimated as the lower limit (LL) and upper limit (UL) of the 95% confidence interval (CI), together with the selected percentiles (P2.5-P97.5). The obtained geometric mean (GM) for As, Cd, Pb, Th, and U were: 0.50 ng/g, 0.32 ng/g, 20.94 ng/g, 0.30 ng/g, and 0.06 ng/g, respectively. The influences of age, sex and lifestyle on results were considered. Women have significantly higher levels of Cd and Th than men. The increased level of Th was observed in the aged group below 40 years, while smokers had significantly higher levels of Pb and double higher level of Cd in the blood than non-smokers (p < 0.05). In comparison with other population groups worldwide, the Serbian population had significantly higher levels of Th and U (up to 100 times higher). These findings could contribute to better understanding of the molecular basis for the development of various health hazards, including the increased incidence of cancer among the Serbian population which need be confirmed by clinical studies.