Dichlorvos Induced Oxidative and Neuronal Responses in Rats: Mitigative Efficacy of Nigella sativa (Black Cumin).

Poisoning from Organophosphates (OPs), especially Dichlorvos (DDVP) has become endemic due to theincreasing use in house hold and agricultural pests control, with most marked effects in the nervous system. However, it isevidenced that natural antioxidants are efficacious against OPs toxicity. Thus, this study investigated the possible antidotalefficacy of Nigella sativa oil (NSO) in Dichlovos (DDVP) induced oxidative and neuronal damages in Wistar rats. DDVPwas administered at sub-chronic daily dosage of 8.8 mg/kg.bw for 7 days and a post-administration of NSO at 1 ml/kg.bwfor the subsequent 7 days. The rats were euthanized on the 15thday, blood sample collected via cardiac puncture, centrifugedand the plasma used for biochemical analysis of total antioxidant capacity (TAC), reduced glutathione (GSH) and totalreactive oxygen species (ROS), while the frontal, occipital and cerebellar cortices and the medulla were removed for histomorphological examinations. The results showed significant (P≤0.05) decrease in plasma TAC and GSH, while a significant(P≤0.05) increase in ROS was recorded, and some vacuolation around the neurons especially in the frontal and cerebellarcortices following DDVP exposure. However, post treatment with NSO was observed to be efficacious in the recovery ofthe oxidative activities and the neuro-architectural integrities. Thus, it can be concluded that the antioxidant capacity of NSOcould be efficacious against OPs induced oxidative damages, especially in dichlorvos accidents.

Repeated Acute Oral Exposure to Cannabis sativa Impaired Neurocognitive Behaviours and Cortico-hippocampal Architectonics in Wistar Rats.

The most abused illicit drug in both the developing and the developed world is Cannabis disposing users to varying forms of personality disorders. However, the effects of cannabis on cortico-hippocampal architecture and cognitive behaviours still remain elusive.  The present study investigated the neuro-cognitive implications of oral cannabis use in rats. Eighteen adult Wistar rats were randomly grouped to three. Saline was administered to the control rats, cannabis (20 mg/kg) to the experimental group I, while Scopolamine (1 mg/kg. ip) was administered to the last group as a standard measure for the cannabis induced cognitive impairment. All treatments lasted for seven consecutive days. Open Field Test (OFT) was used to assess locomotor activities, Elevated Plus Maze (EPM) for anxiety-like behaviour, and Y maze paradigm for spatial memory and data subjected to ANOVA and T test respectively. Thereafter, rats were sacrificed and brains removed for histopathological studies. Cannabis significantly reduced rearing frequencies in the OFT and EPM, and increased freezing period in the OFT. It also reduced percentage alternation similar to scopolamine in the Y maze, and these effects were coupled with alterations in the cortico-hippocampal neuronal architectures. These results point to the detrimental impacts of cannabis on cortico-hippocampal neuronal architecture and morphology, and consequently cognitive deficits.