Vitamin B 12 supplementation improved memory impairment following nicotine withdrawal in adolescent male rats: The role of oxidative stress, inflammatory, BDNF, GFAP, and AChE activity.

The present study aimed to assess the potential effect of vitamin B 12 (Vit B 12 ) on cognition impairment caused by nicotine (Nic) cessation in adolescent male rats. Adolescent male rats were categorized into two main groups as vehicle (normal saline, intraperitoneally), and Nic group in which received Nic (2 mg/kg) from 21 to 42 days of ages and then the Nic group were divided into three groups as withdrawal (the animals returned to regular diet without treatment), second and third groups received bupropion (20 mg/kg), and Vit B 12 at three different doses including 0.5,1, and 1.5 mg/kg by oral gavage as treatments to attenuate Nic withdrawal symptoms. The last group including normal animals received the highest doses of Vit B 12 just in the Nic abstinence period to compare the effect of that with vehicle. In MWM, Vit B 12 and bupropion increased the time spent in the target quadrant that is strongly associated with spatial memory as well as the more time spent with the NORT. Vit B 12 and bupropion modulated both oxidant/antioxidant and inflammatory/anti-inflammatory balance, alongside inhibitory effect on AChE, and GFAP. However, BDNF and amyloid-B showed insignificant difference as compared to Vit B 12 and bupropion. Considering the present results and similar related studies, Vit B 12 can be introduced as a strong anti-oxidant, and anti-inflammatory agent by which probably improved memory impairment caused by Nic addiction accompanied by withdrawal. Further, other mechanisms including activity reduction of AChE, and GFAP should be considered; however, it needs further investigation and larger-scale evidences.