C30), Red cell lysing Buffer Hybri-Max™ (product no. R7757), potassium periodate, iodonitrotetrazolium chloride, superoxide dismutase from bovine erythrocytes, xanthine, xanthine oxidase, and Purpald® were from Sigma-Aldrich Chemie GmbH (Steinheim, Germany). Hydrogen peroxide solution (35%) was purchased from Carl Roth GmbH + Co. KG (Karlsruhe, Germany). The animal experiment was performed in accordance with the guidelines for the care and use of animals for experimental GSK2118436 manufacturer procedures and approved by the Regional Council
of Stuttgart, Germany. Forty male Wistar rats (200-250 g; Janvier, Le Genest Saint-Isle, France) were used because male rats, contrary to female rats, can be housed in groups and randomized into groups of ten animals with similar mean body weights (Table 1) and kept in groups of 3-4 animals per cage under standard conditions (22 ± 2 °C, 55 ± 5% relative humidity, 12 h light/dark cycle). Cages (type IV) were equipped with softwood bedding, a water bottle, and a plastic tube. Animals were fed a modified standard rodent diet (C1000; modifications:
vitamin A, 2,500 IU; vitamin E, 30 mg; selenium, 150 μg; all Selleckchem FG4592 values per kg diet; Altromin Spezialfutter GmbH & Co. KG, Lage, Germany) that was free from synthetic antioxidants, plant polyphenols, and ascorbic acid for an acclimation period of one week and then assigned to one of four treatments: 1) the control see more group received the standard diet only, 2) the cypermethrin group received the standard diet fortified with 350 mg/kg α-cypermethrin, 3) the curcumin group the standard diet fortified with 1,000 mg/kg curcumin, and 4) the cypermethrin + curcumin group the standard diet fortified with a combination of 350 mg/kg α-cypermethrin and 1,000 mg/kg curcumin. Animals had free access to water and feed during the entire experiment, which lasted 7 weeks. Blood was collected from the jugular vein into separate K-heparinized tubes after CO2 anaesthesia
and decapitation. Blood samples were centrifuged (3,000 x g, 10 min) to obtain plasma and both whole blood and plasma samples were stored at -80 °C until analysed. Malondialdehyde (MDA) in whole blood and tissues was analysed according a method described by [25]. Briefly, whole blood or homogenates of liver, kidney, brain and fat (25 μl) mixed with 1% sulphuric acid (75 μl) and 6 M NaOH solution (20 μl) were incubated at 60 °C for 30 min (waterbath). After de-proteinisation with 25% perchloric acid (50 μL) supernatant (100 μl) was mixed with 5 mM 2,4-dinitrophenyl-hydrazine (10 μl) and incubated for 30 min before analysis on a Shimadzu Prominence HPLC. The MDA-2,4-dinitrophenyl-hydrazine adduct was separated on a Reprosil-Pur 120 C18 AQ (250 × 4.6 mm, 5 μm; Trentec) with 50% methanol in formic acid buffer (0.05 M, pH 3.75) at 1 mL/min and detected by UV-VIS at 310 nm.