scholarly works
Permanent URI for this collectionhttps://repository.ui.edu.ng/handle/123456789/498
Browse
3 results
Search Results
Item Neuroprotection of luteolin against methylmercury-induced toxicityin lobster cockroach Nauphoeta cinerea(Elsevier B.V., 2016) Adedara, I. A. || || || || ||; Rosemberg, D. B.; Souza, D. O.; Farombi, E. O.; Aschner, M.; Rocha, J. B. T.Luteolin (3_, 4_, 5, 7-tetrahydroxyflavone) is a polyphenolic compound found in foods of plant origin and has been reported to possess antioxidant and neuroprotective properties. However, there is dearth of information on the beneficial effects of luteolin on methylmercury (MeHg), a long-established neuro-toxic compound in animals and humans. This study evaluated the effect of luteolin on MeHg-inducedbehavioral and biochemical deficits, using lobster cockroach Nauphoeta cinerea as an alternative and complementary animal model. The insects were exposed for 35 consecutive days to either MeHg alone(0.05 mg/g feed) or in combination with luteolin at 0.25, 0.5 and 1.0 mg/g feed. Locomotor behavior was assessed using video-tracking software during a 10-min trial in a novel arena and subsequently, biochemical analyses were carried out using the cockroaches’ heads. Luteolin supplementation dose-dependentlyreversed the MeHg-induced locomotor deficits and enhanced the exploratory profiles of MeHg-exposedcockroaches as confirmed by track and occupancy plot analyses. Luteolin reversed the MeHg-inducedacetylcholinesterase activity inhibition, decreased dichlorofluorescein oxidation and lipid peroxidation levels, but increased total thiol level and catalase and glutathione S-transferase activities in the treated cockroaches. In conclusion, luteolin prevented oxidative stress indices and neurobehavioral deficits in a Nauphoeta cinerea model of MeHg toxicity.Item Neurobehavioral and biochemical changes in Nauphoeta cinerea following dietary exposure to chlorpyrifos(Elsevier Inc., 2016) Adedara, I. A.; Rosemberg, D. B.; Souza, D.; Farombi, E. O.; Aschner, M.; Souza, D. O.; Rocha, J. B. T.The present study aimed to increase our understanding about the mode of toxic action of organophosphate pesticides in insects by evaluating the biochemical and neurobehavioral characteristics in Nauphoeta cinerea exposed to chlorpyrifos (CPF)-contaminated diet. The insects were exposed for 35 consecutive days to CPF at 0.078, 0.15625, 0.3125 and 0.625 μg/g feed. Locomotor behavior was assessed for a 10-min trial in a novel arena and subsequently, biochemical analyses were carried out using the cockroaches’ heads. In comparison to control, CPF-exposed cockroaches showed significant decreases in the total distance traveled, body rotation, turn angle and meandering, along with significant increase in the number of falls, time and episodes of immobility. The marked decrease in the exploratory profiles of CPF-exposed cockroaches was confirmed by track plots, whereas occupancy plot analyses showed a progressive dispersion at 0.15625 μg/g feed group. Moreover, the heads of CPF-exposed cockroaches showed marked decrease in acetylcholinesterase activity and antioxidant status with concomitant significant elevation in dichlorofluorescein oxidation and lipid peroxidation levels in CPF-treated cockroaches. Gas Chromatography–Mass Spectrometry analyses revealed bioaccumulation of CPF in cockroaches exposed to concentrations above 0.078 μg/g feed. The findings from this investigation showed N. cinerea as a value model organism for the risk assessment of environmental organophosphate contamination in insects.Item Biochemical and behavioral deficits in the lobster cockroach Nauphoeta cinerea model of methylmercury exposure(The Royal Society of Chemistry, 2015) Adedara, I. A.; Rosemberg, D. B..; Souza, D. O.; Kamdem, J. P.; Farombi, E. O.; Aschnerd, M.; Rocha, J. B. T.Methylmercury (MeHg) is well-known for its neurodevelopmental effects both in animals and in humans. As an alternative to utilizing conventional animal models, this study evaluated behavioral and biochemical parameters using the nymphs of the lobster cockroach Nauphoeta cinerea. Animals were exposed to MeHg at 0, 0.03125, 0.0625, 0.125, 0.25 and 0.5 mg per g feed for 35 consecutive days. Locomotor activity and exploratory profiles were analyzed using video-tracking software during a 10 minute trial. Subsequently, biochemical estimations were carried out using cockroach heads. MeHg exposure caused behavioral impairment as evidenced by a significant decrease in distance travelled, time spent walking, turn angle and body rotation. The marked decrease in the exploratory profiles of MeHg-exposed cockroaches was confirmed by track plots, whereas occupancy plot analyses revealed a gradual dispersal in homebase formation, starting from 0.0625 mg per g feed. Biochemically, MeHg exposure significantly decreased acetylcholinesterase activity (AChE), an enzyme which plays a pivotal role in neurotransmission. Moreover, MeHg caused increased oxidative stress as evidenced by decreased total thiol levels and glutathione S-transferase (GST) activity, along with increased 2’,7’-dichlorofluorescein (DFCH) oxidation and thiobarbituric acid reactive substance (TBARS) production. In conclusion, these data demonstrated that Nauphoeta cinerea mimics the behavioral and biochemical deficits observed in rodents exposed to MeHg, thus highlighting its validity as an alternative model for basic toxicological studies.