Ivančica Delaš

Oxidative stability and antioxidant activity of bovine, caprine, ovine and asinine milk

This study compares the oxidative stability of fat isolated from bovine, caprine, ovine and asinine milk as well as the antioxidant activity of casein and whey from these milks. Fat from bovine and asinine milk showed the highest oxidative stability. The antioxidant activity of casein and whey was examined before and after an in vitro digestion process. Whey from asinine milk showed the highest antioxidant activity. The antioxidant activity of whey and casein increased after simulated intestinal digestion. In addition, the results of this study showed that asinine whey exhibited radical scavenging activity comparable with the strong synthetic antioxidants butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT).

Carboplatin resistant human laryngeal carcinoma cells are cross resistant to curcumin due to reduced curcumin accumulation

Curcumin is a natural compound that exhibits a wide range of beneficial effects, among them the anti-tumor activity. Recently it was shown that curcumin may be efficient against drug resistant tumor cells. The goal of our investigation was to examine if human laryngeal carcinoma cells resistant to carboplatin display sensitivity to curcumin, as compared to parental cells, and if this sensitivity is altered, to determine the molecular mechanisms that are responsible for it. We found that carboplatin resistant 7T cells were also cross resistant to curcumin. After the treatment with equimolar concentration of curcumin, 7T cells exhibited lower intracellular accumulation of curcumin which coincided with reduced formation of reactive oxygen species (ROS), diminished lipid and DNA damage followed by reduced induction of apoptosis and expression of heat shock protein 70 (Hsp70), as compared to parental HEp-2 cells. However, after the treatment with equitoxic concentration of curcumin, intracellular accumulation and all the explored downstream effects were similar in both cell lines suggesting that resistance of 7T cells to curcumin was based on its reduced intracellular accumulation. Since curcumin accumulates mostly in the membranes, we explored the fatty acid composition of both cell lines, but we did not find any difference between them.

Oxidative status and the severity of clinical symptoms in patients with post-traumatic stress disorder

Background The aim of this study was to measure the parameters of oxidative stress in the blood of patients with post-traumatic stress disorder. Methods The study included 80 male war veterans who participated actively in the Homeland war in Croatia. Volunteers were divided into two groups: 50 veterans diagnosed with post-traumatic stress disorder and 30 without diagnosis. The self-assessment Hospital Anxiety and Depression Scale and the Beck Depression Inventory were used to detect the severity of depression and anxiety in the post-traumatic stress disorder patients. Catalytic concentrations of superoxide dismutase and glutathione peroxidase in erythrocytes and the concentration of malondialdehyde in serum were measured spectrophotometrically. Results Although the catalytic concentrations of erythrocyte superoxide dismutase and erythrocyte glutathione peroxidase were within the reference range for both groups, the values obtained for the post-traumatic stress disorder group were significantly lower (P < 0.001). For serum malondialdehyde concentrations, no statistically significant differences between the groups were found. Conclusions Lower catalytic concentrations of erythrocyte superoxide dismutase and erythrocyte glutathione peroxidase in patients with post-traumatic stress disorder may indicate a weaker response to oxidative stress due to impaired enzyme activity and/or decreased synthesis. Conversely, no significant changes in serum malondialdehyde concentrations suggest a compensated balance and adaptive response to (oxidative) stress.

The Lipid Composition of Subcutaneous Adipose Tissue of Brown Bears (Ursus arctos) in Croatia

The composition of adipose tissue in brown bears (Ursus arctos) is highly variable and depends on an individual’s feeding habits. Fatty acid composition of subcutaneous adipose tissue (SAT) may provide insight into brown bear feeding habits, for which data are scarce. The aim of this study was to determine the lipid composition of SAT and variations in the composition of fatty substances with regard to gender and to assess SAT relative to season and body mass (BM) of brown bears in Croatia. Seventy-six tissue samples of brown bear SAT were analyzed in this study. We found that gender, season, and BM significantly affected the lipid composition of SAT. Both females and males had higher percentages of saturated fatty acids and monounsaturated fatty acids (MUFAs) in SAT in spring than in autumn, while the percentage of polyunsaturated fatty acids (PUFAs) was higher in autumn. The prevalence of MUFAs in SAT and the greater presence of PUFAs in autumn, together with the presence of odd-chain saturated fatty acids, indicate the importance of these fatty acids in brown bear physiology. We suggest that the lipid content of adipose tissue may provide valuable information on changes in brown bear condition in response to feeding habits and the effects of supplemental feeding.