Toxic effects of lead exposure on the brain of rats: Involvement of oxidative stress, inflammation, acetylcholinesterase, and the beneficial role of flaxseed extract

Abstract

The current study was carried out to investigate the effects of low level lead (Pb) exposure on brain tissue antioxidant enzymes activities and acetylcholinesterase (AChE), inflammatory markers (nitrites (NO) and TNF-α), and lipid profile. Furthermore, the possible effects of flaxseed extract to reverse PB-induced toxicity were examined. Female Sprague-Dawley rats were exposed to Pb (200 mg L⁻¹ in drinking water) for three weeks followed by 21 days of orally administrated flaxseed extract (300 mg kg⁻¹). AChE activity increased by 64% and a significant decrease in glutathione (GSH) levels, total antioxidants capacity, glutathione-S-transferase (GST), superoxide dismutase (SOD), and catalase (CAT) activities after Pb exposure. Moreover, NO and α-TNF were increased by 166.5% and 400%, respectively. Finally, Pb exposure increased the brain cholesterol and triglycerides levels. Chronic treatment with flaxseed significantly attenuated cholinergic dysfunction, oxidative stress, and inflammation in the brain after a three week treatment period. Data showed the involvement of factors such as oxidative stress, inflammation, and high expression of AChE activity in Pb-induced neurotoxicity, and showed that flaxseed prevented these adverse effects.

Keywords:

• lead toxicity
• flaxseed
• oxidative stress
• acetylcholinesterase
• brain inflammation