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Background: It has been demonstrated that proteasome inhibitors might be potential anticancer drugs. The copper complexes can be used as specific proteasome inhibitors in tumor cells able to induce apoptosis by the ubiquitin-proteasome pathway. The goal of our study was to test the cytotoxic and proteasome inhibitory effects of five Schiff base Cu(II) complexes - [Cu2(sal-D,L-glu)2(isoquinoline)2] . 2C2H5OH (1), [Cu(sal-5-met-L-glu)(H2O)].H2O (2), [Cu(ethanol)2(imidazole)4][Cu2(sal-D,L-glu)2(imidazole)2] (3), [Cu(sal-D,L-glu)(2-methylimidazole)] (4) on human lung carcinoma cells A549, cervix carcinoma cells HeLa and glioblastoma cells U-118MG., Material and Methods: For the cytotoxic analysis we used MTT test and for monitoring the proteasome inhibition western blot analysis., Results: We have observed different cytotoxic effects of tested complexes on human cancer cells depending on the ligand present in their structure. Cu(II) complexes 4 and 5 were the most effective against A549 cells; all complexes were cytotoxic against HeLa cells and the complex 4 was the most effective against U-118MG. Moreover, we have detected the inhibition of the proteasome activity in human cancer cells A549 by Cu(II) complexes 1, 2 and 4 at IC50 concentration., Conclusion: Results of our study suggest that isoquinoline- and imidazole-based copper complexes could be used as inhibitors of the proteasome system in cancer cells A549 (Tab. 1, Fig. 1, Ref. 26).

Objectives: The aim of this study was to investigate the relationship between thromboxane levels and oxidative stress in children with Crohn´s disease (CD), and examine the effect of natural polyphenolic compounds on thromboxane levels., Methods: This study involved 14 children suffering from CD and 15 healthy controls. Patients were receiving the polyphenolic extract Pycnogenol for 10 weeks. Plasma levels of the static and dynamic forms of thromboxane B2 as well as their metabolite 11-dehydro thromboxane B2 in urine were determined., Results: In comparison to controls, CD patients had significantly higher levels of the static and dynamic forms of thromboxane B2. Pycnogenol decreased the level of the dynamic form of thromboxane B2 after 10 weeks of administration., Conclusions: Paediatric Crohn's disease is associated with higher thromboxane levels. Our results indicate that Pycnogenol administration reduces thromboxane levels, which may positively influence some clinical symptoms of CD such as thromboembolic episodes (Tab. 3, Ref. 49).

Background: Although the iron is an essential element for the physiological functions of cells, tissues and organs, it is also an important inductor of reactive oxygen species (ROS)., Material and Methods: Three groups of human spleen with autoimmune thrombocytopenia (AITP), hereditary spherocytosis (HS) and reference samples stained by haematoxylin and eosin, Perls' reaction for nonheme Fe(III) iron and Alcian blue for glycoconjugates detection were studied., Results: Positive Perls' reaction in both AITP and HS groups was seen. Higher positivity in the HS than in AITP group was observed. HS group showed a higher amount of acidic glycoconjugates deposits than AITP group. Iron overload in HS and AITP leads to overproduction of ROS., Conclusion: We suggest that acidic glycoconjugates deposits are involved in antioxidant defence by elimination and restriction of iron as a ROS inducer (Fig. 4, Ref. 19).