Two of the cis-isomers, namely the AZD6738 purchase 1R,cis- and 1S,cis-stereoisomers make up α-cypermethrin, the most active pair of the cypermethrin isomers [4] and [7]. The urinary concentrations of 3-phenoxybenzoic acid, a cypermethrin metabolite, were positively correlated with the frequency of spraying in Japanese pest control operators [20]. Because of its widespread use, not only persons working with insecticides, but large parts of the population are regularly exposed to

cypermethrin. Cypermethrin metabolites were found in 60% of the collected urine samples in a German population [15] and in >70% of urine samples in a population in the USA [1]. Ingestion of cypermethrin with the diet was identified as the most likely route of exposure in Germany [33]. In rats, oral gavage of single or repeated doses of cypermethrin induces oxidative stress and subsequent oxidative damage in erythrocytes, brain, and liver [9], [13], [17] and [32] and is accompanied by reductions in the activities of the antioxidant enzymes catalase [9] and [32] and superoxide dismutase [9]. In these studies, simultaneous treatment with antioxidants, such as vitamin E, phytochemicals

from propolis, or curcumin, reduced cypermethrin-induced oxidative stress and increased the activities of antioxidant enzymes [9], [13], [17] and [32]. Curcumin is a yellow pigment and lipophilic phenolic compound derived from the rhizome of the plant turmeric (Curcuma longa of the ginger family (Zingiberaceae)) and is used for food colouring and flavouring in private www.selleckchem.com/products/SB-431542.html homes and by the food industry. Among the reported health beneficial effects of dietary curcumin Adenosine triphosphate are its potent antioxidant and anti-inflammatory activities [2]. Previous animal studies have applied single or repeated doses of cypermethrin, equivalent to 10% LD50 or higher, dissolved in oil via gastric intubation [9], [12] and [32], which would represent the rather unrealistic scenario of a high-dose oral exposure once a day in humans. The present experiment was therefore designed

to mimic a constant low-level dietary exposure spread out over the day, which is a more realistic simulation of the exposure pattern observed in humans [33]. The aim of this experiment was to test whether or not this continuous dietary exposure to small doses of α-cypermethrin would induce oxidative stress in rats and, if so, whether or not simultaneous ingestion of curcumin would reduce pesticide-induced oxidative damage. As previous studies focused on acute effects shortly after high-dose exposure, we furthermore aimed to investigate the potential accumulation of pyrethroid-induced oxidative damage over a longer period of seven weeks. α-Cypermethrin (CAS # 52315-07-8; purity ≥97%) was a kind gift from Nanjing Essence Fine-Chemical Co., Ltd. (Nanjing, China). Curcumin (LKT-C8069; CAS # 458-37-7; purity >90%) was from LKT Laboratories Inc. (St. Paul, MN, USA).