Lipid peroxidation of rat myocardial tissue following daunomycin administration

Effects of TBEP on the induction of oxidative stress and endocrine disruption in Tm3 Leydig cells

The flame retardant tris (2-butoxyethyl) phosphate (TBEP) is a frequently detected contaminant in the environment. In the cultured TM3 cells (originated from ATCC), effects of TBEP on the induction of oxidative stress and endocrine disruption were evaluated. It was observed that exposure to 100 μg/mL TBEP for 24 h significantly reduced the viability of TM3 cells. The mRNA levels of genes related to oxidative stress including Sod, Gpx1, Cat, and Gsta1 were changed in a dose-dependent and/or time-dependent manner after exposure to 30 and 100 μg/mL TBEP for 6, 12, or 24 h. Moreover, notable decrease in glutathione (GSH) contents and increases in oxidized glutathione (GSSG) contents as well as the antioxidant enzyme activities like superoxide dismutase, catalase, glutathione peroxidase, and glutathione S-transferase were found in the group treated with 100 μg/mL TBEP for 24 h, indicating that TBEP induced oxidative stress in TM3 Leydig cells. In addition, the expression of genes related to testosterone (T) synthesis including cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), cytochrome P450 17α-hydroxysteroid dehydrogenase (P450-17α), and 17β-hydroxysteroid dehydrogenase (17β-HSD) and T levels in medium were remarkably declined by the treatment of 100 μg/mL TBEP for 24 h. And TBEP could inhibit the expression of P450-17α and 17β-HSD and T levels up-regulated by hCG in TM3 cells. Taken together, these findings indicated that TBEP can induce oxidative stress and alter steroidogenesis in TM3 cells. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1276-1286, 2016.

Polymorphism of Biotransformation Genes and Risk of Relapse in Childhood Acute Leukemia

Leukemia is a hematological malignancy that involves bone marrow. Polymorphism of biotransformation genes plays an important role in primary childhood leukemia and affects the incidence and character of acute leukemia relapse. A biochip designed to assess some polymorphisms of biotransformation genes was used to determine the frequency of the polymorphic variants ofCYP1A1, CYP2D6, GSTT1, GSTM1, MTHFR, MTRR, NQO1, CYP2C9, CYP2C19andNAT2in 332 children with acute lymphoblastic leukemia (ALL) and 71 children with acute myeloblastic leukemia (AML). TheCYP1A1 *1/*2A, GSTT1non null andGSTM1non null genotypes were more frequent in patients with primary leukemia than in relapse. Analysis of theNAT2genotype frequency revealed a characteristic genotype for each type of leukemia, which prevailed in patients with relapse: the genotype341C/-, 481T/-, 590G/G, 857G/Gprevailed in ALL patients with relapse, and the genotype341T/T, 481C/C, 590A/- in AML patients with relapse when compared with patients having primary ALL or AML, respectively. Thus, the polymorphisms ofCYP1A1, GSTT1, GSTM1andNAT2genes can be considered as markers for risk of relapse in childhood acute leukemia and can be used for the prognosis and individualization of standard therapy.

High dose intravenous immunoglobulin g pretreatment: effect on lipid peroxidation and reperfusion injury to the liver

The aim of this study was to examine the effect of intravenous immunoglobulin G (IVIG) compared with that of gadolinium chloride (GdCl3) in the inhibition of Kupffer cell activation on lipid peroxidation after severe total hepatic ischemia/reperfusion (I/R). Male Wistar rats ( n = 40) were randomly divided into four equal groups: a sham-operation group, a control I/R group, and two I/R groups pretreated with either IVIG or GdCl3 intravenously. Following 60 minutes of total hepatic ischemia and 120 minutes of reperfusion, the rats were sacrificed and liver and blood samples collected. Additional animals ( n = 80) were followed up for survival rate determination. Results showed that I/R decreased the survival rate to 10%, increased the levels of aspartate (AST) and alanine (ALT) transaminase and lactate dehydrogenase (LDH) in serum to 2487, 2189, and 4236 IU/L, respectively, and increased malondialdehyde (MDA) levels in liver to 1.552 nmol/g compared with 1.114 nmol/g in the sham operation group. Pretreatment with GdCl3 increased the survival rate to 50% and decreased the levels of AST, ALT, and LDH in serum to 1496, 1298, and 3245 IU/l, respectively. Pretreatment with IVIG increased the survival rate to 60% and decreased the levels of AST, ALT, and LDH in serum to 449, 367, and 1456 IU/l, respectively, and the levels of MDA in liver to 1.153 and 1.148 nmol/g for GdCl3 and IVIG respectively. Histologic examination showed protection of liver parenchyma in the animals treated with GdCl3 or IVIG.

Role of exogenous melatonin in reducing the nephrotoxic effect of daunorubicin and doxorubicin in the rat

The aim of these studies was to examine the nephroprotective effect of melatonin following the anthracycline administration [daunorubicin (DNR); doxorubicin (DOX)] in rats. Application of these drugs in chemotherapy is limited because of their cardiotoxicity and nephrotoxicity. Rats of the Buffalo strain were divided into groups according to the cytostatic drug used, its dose and sequence of administration [DNR or DOX single (i.v.) dose of 10 mg/kg b.w., i.e. acute intoxication and 3 mg/kg b.w. (i.v.) weekly for 3 wk, subchronic intoxication]. Melatonin was administered subcutaneously before and after every injection of a cytostatic drug at a dose of 10 mg/kg b.w. The severity of renal alterations was examined both biochemically [levels of lipid peroxidation markers, malonyldialdehyde (MDA) and 4-hydroxyalkenals (4-HDA)], or histologically. A statistically significant decrease in renal damage was noted after melatonin administration to acutely or subchronically intoxicated DNR-treated and DOX-treated rats. Biochemical assays revealed significant decreases in MDA and 4-HDA levels following application of melatonin during subchronic DNR or DOX intoxication. In summary, melatonin was found to exert a protective effect on the kidney, which was particularly evident after subchronic DOX and DNR intoxication, using both histological or biochemical methods.

Effect of glutathione S-transferases on the survival of patients with acute myeloid leukaemia

The objective of the study was to investigate the effect of genetic polymorphisms in glutathione S-transferases (GST) on the survival of acute myeloid leukaemia patients receiving adriamycin induction therapy. A total of 89 patients were included in the study. Patients who carried at least one GSTM1 allele had trend towards a better survival (mortality rate ratio (RR) 0.588; 95% CI 0.334-1.036) than GSTM1*0/0 patients. However, at low accumulated adriamycin dose, GSTM1*0/0 cases had a better survival than people expressing the gene (RR=6.1; 95% CI=1.2-11.0). The GSTT1 and GSTP1 genotype did not influence the survival in any of the groups.

Role of exogenous melatonin in reducing the cardiotoxic effect of daunorubicin and doxorubicin in the rat

The aim of the studies was to examine the cardioprotective effect of melatonin during the anthracycline administration (daunorubicin, doxorubicin) in rats. Application of these drugs in chemotherapy is limited because of their cardiotoxicity. Rats of Buffalo strain were divided into groups according to the cytostatic drug used, its dose and sequence of administration (single intravenous [i.v.] dose of 10 mg/kg b.w., i.e., acute intoxication; 3 mg/kg b.w. weekly for 3 weeks, subchronic intoxication). Melatonin was administered subcutaneously before and after every injection of a cytostatic drug at a dose of 10 mg/kg b.w. The degree of cardiac muscle cell alterations was examined either histologically (Mean Total Score technique and the Billingham scale), or biochemically (levels of lipid peroxidation markers, malonyldialdehyde, and 4-hydroxyalkenals). Statistically significant decrease in cardiac muscle cell damage was noted with an aid of the Billingham scale after melatonin administration in acutely intoxicated doxorubicin-treated rats (p < 0.001). The similar phenomenon was observed using the Mean Total Score technique in case of acute daunorubicin or doxorubicin (p < 0.01 and p < 0.001, respectively) intoxications. A significant reduction in cardiac muscle cell lesions was detected either by the Billingham scale or by the Mean Total Score technique during subchronic intoxication with either of the anthracyclines when melatonin was given. Biochemical assays revealed significant decreases in malonyldialdehyde and 4-hydroxyalkenals levels following application of melatonin during either acute doxorubicin (p < 0.05) or subchronic daunorubicin (p < 0.01) intoxication. In summary, melatonin was found to exert a protective effect on the cardiac muscle cells, which was particularly evident after acute doxorubicin or subchronic daunorubicin intoxication, using either histological or biochemical methods.