The Effects of Mkpuru Mmiri Consumption on Cognitive Performance and Brain Histology in an Animal Study

Abstract

Mkpuru mmiri, popularly known as ice or methamphetamine (METH) is one of the illegal substances that young people in Nigeria abuse most frequently. The purpose of the study is to determine how methamphetamine affects the cognitive-motor behavior of Wistar rats. In the study, twenty-five Wistar rats weighing between 117 and 138 grams were split into five groups: group A had only rat feed and water, group B - D received doses of METH ranging from 5 mg/kg to 20 mg/kg, and group E received a dose of 5 mg/kg of diazepam. Neurobehavioral tools such as the navigator maze test, elevated plus maze and beam walk were used to assess the rats’ memory, anxiety-related behavior, balance, motor coordination, and working memory respectively. Two weeks after the injection, samples were taken and examined for oxidative stress markers (Malondialdehyde - MDA) and tissue antioxidant indicators (Superoxide dismutase - SOD, Glutathione - GSH, and Total Antioxidant Capacity - TAC). The data were analyzed using SPSS and post hoc LSD and the significance level was established at p<0.05. The results showed that the test groups' body weight was significantly lower than the control groups' (p<0.05). The test groups' relative brain weights increased significantly (p<0.05) when compared to the control group. The data also showed a significantly (p<0.05), level of antioxidant enzymes (SOD, GSH, and TAC levels) and a significantly (p<0.05) greater level of MDA when compared to the control group. When comparing the test groups' cognitive abilities to the controls, the experimental rats' cognitive powers significantly declined. The study's conclusion demonstrated that chronic consumption of methamphetamine may deteriorate cognitive function.