RESUMEN
Oxidative stress is an important pathomechanism of neurological disorders such as Alzheimer disease and Parkinson disease, cardiovascular disorders and many others. This study sought to verify whether extra-virgin olive oil (EVOO), lipophilic fraction (OOLF) and hydrophilic fraction (OOHF) exerted a brain protective effect against the oxidative stress caused by 2,4-dichlorophenoxyacetic acid (2,4-D) pesticide at a dose of 5 mg/kg body weight. 2,4-D, EVOO and its fractions were administered to rats by gavages for four consecutive weeks. Oxidative stress was assessed by measuring brain lipid peroxide level, acetylcholinesterase (AChE), antioxidant enzyme activities and fatty acid composition. 2,4-D induced a decrease in both plasma and brain acetylcholinesterase activity and a rise in Brain TBARS (Thiobarbituric acid reactive substances) level and antioxidant enzyme activities compared with the control group. These changes were partly reversed by either EVOO or its fractions oral administration to 2,4-D treated rats. EVOO enhanced a neuroprotective effect evaluated by the restoration of brain fatty acid composition especially the level of docosahexaenoic acid (DHA). Our results indicate that EVOO exerts a neuroprotective activity against oxidative damage in brain induced by 2,4-D, which could be attributed to its antioxidative property.
RESUMEN
In this study, a cohort of farmers from the Mateur region in the North of Tunisia, were interviewed and examined for the biochemical effects of pesticides. We studied their haematological profile, lipid parameters, serum markers of nephrotoxicity and hepatotoxicity. We also evaluated the activities of Butyrylcholinesterase (BChE), Acetylcholinesterase (AChE) and thiolactonase-paroxonase (PON). Moreover, lipid peroxidation and activities of antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) were determined. The duration of pesticide use and the farmers' age were considered in the analysis. Our results revealed significant differences in some haematological parameters, in liver and kidney functions, in the lipidic status of the pesticide-exposed group. We also reported an increase in the index of incidence of cardiovascular risk in farmer populations. A significant decrease in AChE, BChE and PON levels was found among farmers. Lipid peroxidation, however, increased. The activities of SOD and CAT were remarkably elevated in farmer populations. There was a significant relation between changes in biological markers, the duration of pesticide use and the farmers' age. This study indicates that a long-term exposure to pesticides may play an important role in the development of vascular diseases via metabolic disorders of lipoproteins, lipid peroxidation and oxidative stress, inhibition of BChE and decrease in thiolactonase-PON levels.