Cerebral Ganglionic Variations and Movement Behaviors of Lumbricus Terrestris on Exposure to Neurotoxin

Background: Invertebrate worms serve as models for understanding the features of neurological functions. Acrylamide (ACR), the well-known neurotoxin, is a water-soluble chemical widely used in various industrial and laboratory processes. ACR is also found in food items which are cooked under high temperature.

Purpose: The study attempts to assess the neuropathological changes in cerebral ganglions along with the locomotion and neuronal behavior of Lumbricus terrestris on ACR intoxication.

Methods: The dosage of acrylamide induced neurotoxicity ranged from 0-17.5 mg/kg body weight for 7 days. The time/dose dependent changes in the oxidant and antioxidant status, activities of Na(+)/K(+)ATPase, Ca(2+)/Mg(2+) ATPase and 5' Nucleotidase were assessed along with the locomotor behavioral analysis.

Result: The activities of super oxidase dismutase and catalases were not altered appreciably. However, the glutathione family, lipid peroxide, protein carbonyl content and vitamin C did show significant variations (p<0.001) in a dose-dependent manner, depicting more of oxidative stress, when compared to control worms. The activities of Na(+)/K(+) ATPase was significantly affected (p<0.001) at 3.5 mg/kg bw itself while those of both Ca(2+) and 5' Nucleotidase were found to be affected at 7.0 mg/kg bw of ACR. Mg(2+) ATPase showed significant reduction (p<0.001) in its activity only at 10.5 mg/kg bw of ACR. These dose dependent biochemical variations observed were found to be linked with the behavior of the worms as evident from the latency of movement in a dose-dependent manner which is less pronounced at 7.0 mg and more pronounced at 17.5 mg/kg bw of ACR.

Conclusion: The study suggests that ACR disrupts GSSS/GSH balance and perturbs ionic homeostasis in worms and thus affect the motor function highlighting their (GSH-ions) interrelationship in influencing neuromuscular activity. These simple analyses implicate that the cerebral ganglionic variations in the worms may be useful to appreciate the pathology of the neurological diseases (provided sophisticated analyses are employed) especially which involve movement dysfunction, where the brain tissue samples from the affected human patients are scarce.