Evaluation of Oxidative and Antioxidative Parameters in Pediatric Hematopoietic SCT Patients

Conditioning regimens preceding hematopoietic SCT (HSCT) usually consist of high-dose chemotherapy. Chemotherapy and radiation therapy are associated with increased formation of free radicals and depletion of critical plasma and tissue antioxidants. Oxidative stress and antioxidant depletion have been described during the transplantation period in HSCT patients. In a limited number of studies, it was observed that the conditioning regimen resulted in oxidative stress and antioxidant depletion in HSCT patients. The objective of this study was to look for further evidence of oxidative stress and antioxidant status in pediatric HSCT patients. In this study, blood samples were collected from 21 pediatric allo-HSCT patients before and after conditioning therapy. Erythrocyte and plasma malondialdehyde (MDA) levels, erythrocyte reduced and oxidized glutathione (GSH) levels, erythrocyte antioxidant enzymes activities, plasma α-tocopherol and β-carotene levels were determined. After high-dose chemotherapy, erythrocyte and plasma MDA levels increased. Reduced GSH levels decreased whereas oxidized GSH levels increased first and then decreased significantly compared with the values before the chemotherapy regimen. It was also observed that catalase, superoxide dismutase and GSH-S-transferase activities decreased, but there was no change in GSH peroxidase activity. On the other hand, plasma α-tocopherol levels increased, but β-carotene levels did not change.Wo

Cofactor metals and antioxidant enzymes in cisplatin-treated rats: effect of antioxidant intervention

WOS: 000369918800002PubMed ID: 25346999We explored the association between the activities of antioxidant enzymes and their metallic cofactors in rats treated with cisplatin. The antioxidant effects of aminoguanidine, and a combination of vitamins E and C were investigated. Plasma platin was significantly lower than liver and kidney. Cisplatin treatment caused significant increase in plasma Se-glutathione peroxidase activity. Activities of Se-glutathione peroxidase, glutathione S-transferase, catalase and Cu, Zn-superoxide dismutase have been found to be significantly decreased in liver and kidney compared to controls. Zn levels in these organs were diminished upon cisplatin treatment, while levels of Cu were unaffected. Interestingly, levels of iron, the cofactor of catalase, were found to be significantly increased in liver and kidney. Intervention with aminoguanidine or vitamins was generally prevented cisplatin-caused changes in the activity of enzymes and in the tissue levels of cofactor metals. These observations suggest that relation between activities of enzymes and levels of cofactor metals is multifactorial.Hacettepe University Research Center OfficeHacettepe University [04 DD 02 301 002]The authors declare that there is no conflict of interest. This study was supported by Hacettepe University Research Center Office, Grant no. 04 DD 02 301 002

Polyphenolic Constituents And Antioxidant Potential Of Geranium Stepporum Davis

The crude MeOH extract prepared from the aerial parts of G. stepporum and its EtOAc, n-BuOH, H(2)O subextracts were screened for their inhibitory activity on H(2)O(2)-induced lipid peroxidation in human red blood cells. The EtOAc subextract was found to be the most active one and its chemical composition was further analysed. Six polyphenolic secondary metabolites including quercetin (1), rutin (2), methyl gallate (3), pusilagin (4), 1,3,6-tri-O-galloyl-beta-glucospyranose (5) and 1,2,3,4,6-penta-O-galloyl-beta-glucopyranose (6) were isolated from the EtOAc extract by successive chromatographic methods (Sephadex CC, silica gel CC and P-TLC). The structures of the isolates were elucidated by 1D- and 2D-NMR and MS. This is the first report of occurrence of hydrolysable tannins in G. stepporum.Wo

Antioxidant Effects of Secondary Metabolites from Geranium psilostemon

An investigation was made of the effects on endogenous antioxidant enzyme activities and H2O2-induced lipid peroxidation inhibition in human red blood cells of the crude MeOH extract and its EtOAc, n-BuOH, and H2O sub-extracts obtained from aerial parts of Geranium psilostemon Ledeb., as well as compounds isolated from the most active EtOAc extract. Gallic acid (1), methyl gallate (2), pusilagin (3), 1,3,6-tri-O-galloyl-beta-glucopyranoside (4), 1,2,3,4,6-penta-O-galloyl-beta-glucopyranoside (5), kaempferol (6), quercetin (7), kaempferol 7-O-alpha-rhamnopyranoside (8), and quercetin 7-O-alpha-rhamnopyranoside (9) were isolated from the aerial parts of the title plant, and their structures identified from spectroscopic (UV, 1D- and 2D- NMR) and spectrometric (TOF-MS) data. All extracts and isolated compounds inhibited H2O2-induced lipid peroxidation and also enhanced the activity of superoxide dismutase (SOD) and catalase (CAT)

Antioxidant secondary metabolites from Geranium lasiopus Boiss. & Heldr.

Chromatographic studies on the EtOAc soluble portion of the MeOH extract of Geranium lasiopus led to the isolation of eight flavonoids (kaempferol (1), quercetin (2), quercetin 3-O-beta-glucopyranoside (3), quercetin 3-O-beta-galactopyranoside (4), kaempferol 3-O-alpha-rhamnopyranosyl-(1 -> 6)-beta-glucopyranoside (5), quercetin 3-O-alpha-rhamnopyranosyl-(1 -> 6)-beta-glucopyranoside (6), kaempferol 3-O-alpha-rhamnopyranosyl-(1 -> 2)-beta-glucopyranoside (7) and quercetin 3-O-alpha-rhamnopyranosyl-(1 -> 2)-beta-glucopyranoside (8)), two simple phenolic compounds (gallic acid (9) and its methyl ester (10)) and a hydrolysable tannin (pusilagin (11)). The structures of the compounds were elucidated by 1- and 2-dimensional NMR techniques (H-1, C-13, COSY, HMBC, HMQC) and ESI-TOF-MS spectrometry. Inhibitory effects on H2O2-induced lipid peroxidation in human red blood cells of the different extracts of G. lasiopus, as well as isolated compounds, were investigated. All tested compounds showed comparable or higher activity than that of ascorbic acid and trolox