Alterations of Na+/K+-ATPase, cholinergic and antioxidant enzymes activity by protocatechuic acid in cadmium-induced neurotoxicity and oxidative stress in Wistar rats

Background: This study assessed the possible protective mechanisms of protocatechuic acid (PCA) against cadmium (Cd)-induced oxidative stress and neurotoxicity in rats.

Methods: Male wistar strain rats weighing between 150-160g were purchased and acclimatized for two weeks. The rats were divided into seven groups of seven each; NC group received normal saline, CAD group received 6mg/kg of Cd-solution, CAD+PSG group received Cd-solution and prostigmine (5mg/kg), CAD+PCA-10 and CAD+PCA-20 groups received Cd-solution and PCA (10mg/kg and 20mg/kg) respectively, PCA-10 and PCA-20 groups received 10mg/kg and 20mg/kg PCA each. Animals were administered normal saline, Cd and PCA daily by oral gavage for 21days. After which the Animals were sacrificed, the brain excised, homogenized and centrifuged. The activities of enzymes (Na⁺/K⁺-ATPase, cholinesterases, catalase, Glutathione Peroxidase, superoxide dismutase) and levels of oxidative stress markers (lipid peroxidation and reduced glutathione) linked to neurodegeneration were subsequently assessed.

Results: Significant (p<0.05) alterations in the Enzyme activities and levels of oxidative stress markers were observed in CAD group when compared to the NC group. However, the activities of the enzymes were reversed in CAD+PSG and CAD+PCA groups.

Conclusions: PCA may protect against cadmium-induced neurotoxicity by altering the activities of Na⁺/K⁺-ATPase, acetylcholinesterase, butyrylcholinesterase and endogenous antioxidant enzymes.