Interaction of four low dose toxic metals with essential metals in brain, liver and kidneys of mice on sub-chronic exposure

• Low dose toxic metals were exposed to mice for 120 days.
• Exposure to Pb increased brain Mg and Cu by 55.5% and 266% respectively.
• Increased Mg resulted from metabolic activity of brain to combat insults.
• Reduced liver Ca resulted from inhibition of Ca-dependent ATPase through binding with thiol groups.

This study reports on interactions between low dose toxic and essential metals. Low dose Pb (0.01 mg/L), Hg (0.001 mg/L), Cd (0.005 mg/L) and As (0.01 mg/L) were administered singly to four groups of 3-week old mice for 120 days. Pb exposure increased brain Mg and Cu by 55.5% and 266%, respectively. Increased brain Mg resulted from metabolic activity of brain to combat insults, whiles Cu overload was due to alteration and dysfunction of CTR1 and ATP7A molecules. Reduction of liver Ca by 56.0% and 31.6% (on exposure to As and Cd, respectively) resulted from inhibition of Ca-dependent ATPase in nuclei and endoplasmic reticulum through binding with thiol groups. Decreased kidney Mg, Ca and Fe was due to uptake of complexes of As and Cd with thiol groups from proximal tubular lumen. At considerably low doses, the study establishes that, toxic metals disturb the homeostasis of essential metals.