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1

The role of copper in tumor angiogenesis ? clinical implications

100%

Nasulewicz A., Opolski A.

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EN

This review concerns a brief introduction into the basics of tumor blood vessels development as well as the regulatory mechanisms of this process. The role of copper ions in tumor angiogenesis is discussed. The new antiangiogenic therapies based on a reduction of copper levels in tumor microenvironment are reviewed.

2

Effect of converting enzyme inhibitor on copper and iron concentrations of blood plasma in calves during the neonatal period

88%

Skrzypczak W., Dratwa-Chalupnik A., Ozgo M., Michalerk K., Lepczynski A., Hejza K., Siwa J.

Folia Biologica

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2010

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vol. 58

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issue 1-2

119-124

EN

The converting enzyme catalyzes the conversion of angiotensin I to angiotensin II. Ang II is the key component of the renin-angiotensin-aldosterone (RAA) system, regulating water-electrolyte balance in newborn calves. Captopril is an inhibitor of the angiotensin-converting enzyme. The aim of this study was to examine the effect of captopril-induced reduction of convertase activity on copper and iron concentrations of blood plasma in calves. The experiment was carried out on 10 Holstein-Friesian female calves, during the first week of life. Copper and iron concentrations in blood plasma were examined before and after captopril administration (0.5, 1, 2, 4, and 6 hours after giving the inhibitor) on subsequent days of the experimental period. The results demonstrated that the copper concentration of blood plasma increased with age. On the seventh day, the copper concentration stabilised at the level observed in adult cattle. Measured before captopril administration, the iron concentration in blood plasma changed: the highest iron concentration was observed on the first day of life, which was followed by a decrease on the third day, and thereafter an increase on the seventh day. These changes may significantly influence the neonatal adaptation of newborn calves, particularly hemopoiesis efficiency. Captopril did not cause statistically significant changes in plasma copper concentration in calves. However, the reduction of angiotensin convertase activity induced by captopril administration resulted in a drop of plasma iron concentration, observed already within 1-2 hours after administration of the inhibitor, and especially within two days post partum. The results indicate that an efficient mechanism maintaining a constant concentration of selected minerals may involve changes in the reabsorption of these minerals from the system fluids to tissues.

3

DNA damage in mouse lymphocytes exposed to curcumin and copper

75%

Urbina-Cano P., Bobadilla-Morales L., Ramirez-Herrera M. A., Corona-Rivera J. R., Mendoza-Magana M. L., Troyo-Sanroman R., Corona-Rivera A.

Journal of Applied Genetics

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2006

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vol. 47

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issue 4

377-382

EN

Dietary polyphenolics, such as curcumin, have shown antioxidant and anti-inflammatory effects. Some antioxidants cause DNA strand breaks in excess of transition metal ions, such as copper. The aim of this study was to evaluate the in vitro effect of curcumin in the presence of increasing concentrations of copper to induce DNA damage in murine leukocytes by the comet assay. Balb-C mouse lymphocytes were exposed to 50 M curcumin and various concentrations of copper (10 M, 100 M and 200 M). Cellular DNA damage was detected by means of the alkaline comet assay. Our results show that 50 M curcumin in the presence of 100?200 M copper induced DNA damage in murine lymphocytes. Curcumin did not inhibit the oxidative DNA damage caused by 50 M H2O2 in mouse lymphocytes. Moreover, 50 M curcumin alone was capable of inducing DNA strand breaks under the tested conditions. The increased DNA damage by 50 M curcumin was observed in the presence of various concentrations of copper, as detected by the alkaline comet assay.

4

Protective in vivo effect of curcumin on copper genotoxicity evaluated by comet and micronucleus assays

75%

Corona-Rivera A., Urbina-Cano P., Bobadilla-Morales L., Vargas-Lares J. J., Ramirez- H. M. A., Mendoza-Magaua M. L., Troyo-Sanroman R., Diaz-Esquivel P., Corona-Rivera J. R.

Journal of Applied Genetics

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2007

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vol. 48

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issue 4

389-396

EN

Curcumin is a phytochemical with antiinflammatory, antioxidant and anticarcinogenic activities. Apparently, curcumin is not genotoxic in vivo, but in vitro copper and curcumin interactions induce genetic damage. The aim of this study was to test if in vivo copper excess induces DNA damage measured by comet and micronucleus assays in the presence of curcumin. We tested 0.2% curcumin in Balb-C mice at normal (13 ppm) and high (65, 130 and 390 ppm) copper ion concentrations. The comet and micronucleus assays were performed 48 hr after chemical application. Comet tail length in animals treated with 0.2% curcumin was not significantly different from the control. Animals exposed to copper cations (up to 390 ppm) exhibited higher oxidative DNA damage. Curcumin reduced the DNA damage induced by 390 ppm copper. We observed statistically significant increase in damage in individuals exposed to 390 ppm copper versus the control or curcumin groups, which was lowered by the presence of curcumin. Qualitative data on comets evidenced that cells from individuals exposed to 390 ppm copper had longer tails (categories 3 and 4) than in 390 ppm copper + curcumin. A statistically significant increase in frequency of micronucleated erythrocytes (MNE/10000TE) was observed only in 390 ppm copper versus the control and curcumin alone. Also cytotoxicity measured as the frequency of polychromatic erythrocytes (PE/1000TE) was attributable to 390 ppm copper. The lowest cytotoxic effect observed was attributed to curcumin. In vivo exposure to 0.2% curcumin for 48 hr did not cause genomic damage, while 390 ppm copper was genotoxic, but DNA damage induced by 390 ppm copper was diminished by curcumin. Curcumin seems to exert a genoprotective effect against DNA damage induced by high concentrations of copper cations. The comet and micronucleus assays prove to be suitable tools to detect DNA damage by copper in the presence of curcumin.

5

The geochemical profile of bottom sediments in the Domiaza (Oder river estuary, northwest Poland)

51%

Piotrowski S., Laba-Mydlowska E.

Oceanological and Hydrobiological Studies

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2003

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issue 4

79-115

EN

The Domiaza is a fragment of the Oder river estuary situated north of Szczecin. This area is exposed to complex hydrological processes and strong anthropogenic pressure. Key physical and chemical parameters of the Domiaza sediments (fraction < 2mm), e.g., dry residue (Ds), ignition loss (Iz), CaCO3 and organic carbon content, show high coefficients of variation (over 60%). Similar variation is typical of the heavy metal concentrations (Cu, Zn, Pb, Co, Cd and Hg) and the organic carbon content in the fraction smaller than 0.20 mm. The spatial distribution of the examined parameters in the Domiaza sediments results from the dynamics of this environment, especially the heavy watercraft traffic and the continuous dredging of the Szczecin-Swinoujscie water lane. Concentrations of Cd, Cu, Zn, Pb and Co found in the Domiaza sediments are higher than those found in the geochemical background of Poland, while concentrations of mercury are comparable. Moreover, the concentrations of Cu, Zn, Pb and Cd found in the Domiaza sediments are higher than the average concentrations of these metals in adjacent areas (Oder River, Dabie Lake, Szczecin Lagoon), but the concentrations of Hg and Co are comparable or lower depending on the area of reference. A survey of heavy metals concentrations conducted in 1999 detected higher than average concentrations of Cu, Zn, Pb, and particularly Co (twice) and Hg (over thirty times), and lower concentrations of Cd in comparison with the average levels of 1996. The reason for these differences was the selective inflow of heavy metals to the Domiaza area after the disastrous flood of 1997.

6

Alzheimer's beta-amyloid peptide as a source of neurotoxic free radicals: the role of structural effects

51%

Pogocki D.

Acta Neurobiologiae Experimentalis

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2003

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vol. 63

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issue 2

131-145

EN

This mini review gives a brief overview over the oxidation mechanism of methionine (Met), relevant for processes which may lead to the oxidation of amyloid beta-peptide (betaAP), involved in the pathogenesis of Alzheimer?s disease. The Cu II-catalysed oxidation of C-terminal Met 35 in AP depends on the secondary structure of the peptide. That seems to be the key to the known propensities of this peptide to form reactive oxygen species and free radicals. The pro-oxidant character of betaAP is not associated with its -beta sheet insoluble form. On the contrary, the alpha-helically organised structure is responsible for betaAP redox-related cytotoxicity.

Refine search results

The role of copper in tumor angiogenesis ? clinical implications

Effect of converting enzyme inhibitor on copper and iron concentrations of blood plasma in calves during the neonatal period

DNA damage in mouse lymphocytes exposed to curcumin and copper

Protective in vivo effect of curcumin on copper genotoxicity evaluated by comet and micronucleus assays

The geochemical profile of bottom sediments in the Domiaza (Oder river estuary, northwest Poland)

Alzheimer's beta-amyloid peptide as a source of neurotoxic free radicals: the role of structural effects