Glutathione and glutathione-related enzymes in rats exposed to dimethoate and/or pyrantel

Abstract

The study was undertaken to examine the effect of single and combined administration of dimethoate (an OP insecticide) and pyrantel embonate (an anthelmintic agent) on the concentration of reduced glutathione (GSH) and the activity of glutathione peroxidase (GPx) and glutathione reductase (GR) in rats. Dimethoate (Group I) was administered to rats at a dose of 1/10 LD 50 for 5 consecutive days and pyrantel embonate (Group II) at a dose of 1/5 LD 50 for 3 consecutive days. The animals of group III were given both of the mentioned above compounds in the same manner as group I and II, but pyrantel embonate was applied on day 3, 4, and 5 from the beginning of dimethoate intoxication. Material from 6 rats randomly selected from each group was obtained after 3, 6 and 12 hours and 2, 7 and 14 days following the last applied dose of the compounds under study. It was found that application of pyrantel embonate caused only slight changes in the analysed parameters i.e. GSH, GPx and GR. Dimethoate administration caused disturbances in the antioxidative system manifested as a decrease in GSH concentration in the liver (max. -37.7% after 6 hours) and an increase of GPx and GR activities in erythrocytes (max. -21.7% and 29.6% after 3 hours, respectively), compared to the control group. The profile of changes after combined intoxication was similar, but their intensity was higher compared to the group of animals exposed to dimethoate only. Based on current studies, it was concluded that both dimethoate and pyrantel embonate at the applied doses showed a pro-oxidative activity.

Occupational exposure to organophosphorus and carbamates in farmers in La Cienega, Jalisco, Mexico: oxidative stress and membrane fluidity markers

“…A decrease in GSH/GSSG was observed as a result of exposure to OPs, carbamates and paraquat [ 7 , 9 , 23 , 24 , 27 , 39 – 41 ]. However, unlike our results, studies that have analyzed GSH and GSSG specifically in erythrocytes after exposure to OPs (as was done in the present study) reported high levels [ 42 , 43 ]. Particularly, differences in the GSH and GSSG responses depend not only on the type of sample analyzed, but also the type of OPs involved, and the duration of exposure [ 42 ].…”

“…The higher values to GSH and GSSG in the not exposed group, suggests that exposure to pesticides (regardless of the duration in years of use) affects human health, since the only group that maintained its functional antioxidant activity was not exposed group. On the other hand, the low levels of GSH and GSSG markers in exposed subgroups may be due to the low antioxidant defense induced by chronic exposure to pesticides, as reported by Spodniewska et al [ 42 ] and Georgiadis et al [ 43 ]. Conversely, other studies show that pesticide exposure may increase the GR activity, which converts GSSG to GSH, as an adaptation of the organism to prevent permanent oxidative damage [ 26 , 34 , 41 ].…”

Food safety in Thailand 1: it is safe to eat watermelon and durian in Thailand

“…An endocrine disrupter pesticide endosulfan has been shown to reversibly inhibit human CYP3A4 enzyme [56]. Dimethoate pretreatment in rats caused an increase in the activities of glutathione peroxidase and glutathione reductase, as compared to the control animals [57]. A recent study has also shown that a new fungicide propiconazole inhibited P-glycoprotein (P-gp) transporter protein with an inhibition potency similar to erythromycin [35].…”

Effect of enrofloxacin and chlorpyrifos on the levels of vitamins A and E in Wistar rats

“…On the other hand, a very limited number of studies concern the consequences caused by the co-administration of pesticides and medicaments (Babu et al, 2006;Buyukokuroglu et al, 2008), and only individual ones focus on the oxidative stress (Spodniewska et al, 2014). A decrease in the contents of both vitamin A and E was noted in our study following the enrofloxacin and chlorpyrifos co-administration.…”