Neuroprotective Potential of Vitamin B-12 Against Cadmium–Induced Neuroinflammation Mediated Memory Dysfunctions in Adult Albino Mice

Abstract

Cadmium induces neurotoxicity in brain and results in increased enzymatic functions, accumulation of Amyloid beta plaque and Neuo Fibrillary Tangles (NFTs) causing neurodegenerative diseases. The purpose of the present work was to investigate the anti-inflammatory or anti-oxidative potential of vitaminB12 against Cd -induced memory impairment and mechanism of signaling pathway of vitamin-B12 protection in Cd-induced neuroinflammatory in mice model. Male albino mice of BALB/C trait of age 7 to 8 weeks and weighing about (30-32±3g) were used as model animal in the study. All mice were divided in three groups. Control Group (CG) treated with 0.9% saline (1mL/Kg), Cd Cl2 administered Group (CD) (1mg/kg) and Cd +Vitamin administered group (CV) B-12 (500µg/kg). CD group was treated with Cd Cl2 for three weeks on alternate days while CV group was treated with Vitamin B12 and toxin CdCl2 for the next two weeks intraperitonealy. Behavior tests like Morris Water Maze (MWM) and Y-Maze (YM) tests were conducted on the experimental mice to study the neuro protective potential of Vitamin-B12 against CdCl2 induced memory dysfunctions. After completing the above procedures, mice were sacrificed and the brains of each group were collected for protein quantification step and western blotting. The Immuno blots of Iba-1, NF-kB, TNF-α, IL-1β, BACE1 and Aβ proteins in the brain homogenates of CD and CV mice confirm the anti-neuroinflammatory potential of vitamin-B12 against Cadmium –induced Neuroinflammation. Escape latency of CV group mice receiving Methylcobalamine was less and showed better performance in MWM test. The results of Y-maze test also showed that the spontaneous percentage alternation of CD group mice was less than CV and CG group of mice. Immuno blot of p-Akt confirm the signaling pathways of vitamin-B12 protection in Cd-induced neuroinflammatory mediated memory-impairment in the model mice. Our findings suggest that Vitamin-B12 could be a potent candidate drug for treating cognitive dysfunctions due to its anti-inflammatory and anti-oxidative potential. Our study also shows that Vitamin-B12 activates p-Akt signaling pathway along with decreasing the NF-Κb, TNF-α and IL-1β to protect the brain of mice against CdCl2 neurotoxicity.