Impact of Selected Metals and Vitamins (C, B6, B9) on Oxidative Damage in Human Erythrocytes

Batool Khalil Mohammed
University of Kirkuk, College of pharmacy, Department of Pharmaceutics, Kirkuk, Iraq

Daroon Issam Raffik
University of Kirkuk, College of Science Department of chemistry, Kirkuk, Iraq

Israa Nibras Qader
University of Kirkuk, College of Science Department of chemistry, Kirkuk, Iraq

ABSTRACT

This study evaluated the toxic effects of selected heavy metals on human erythrocytes ex vivo, focusing on both direct toxicity and oxidative damage. The results indicated that the toxicity of the tested metals followed the order: K >> Cu >> Ba >> Zn >> Ag. Additionally, the study examined the impact of vitamins B₆, B₉, and C on the percentage of hemolysis in erythrocytes exposed to heavy metals. The findings showed that increasing the concentration of these vitamins reduced the percentage of hemolysis compared to the hemolysis induced by K, Cu, Ba, Ag, and Zn. However, specific combinations, including Vit. C: K, Vit. B₆: Ba, Vit. B₆: K, Vit. B₉: Ba, and Vit. B₉: Ag, led to an increase in hemolysis at higher vitamin concentrations. This suggests that, under certain conditions, excessive levels of vitamins (C, B₆ and B₉) may enhance erythrocyte damage in the presence of these metals. The study also assessed the toxicity of the vitamins themselves, with the following toxicity order: Vit. C >> Vit. B₉ >> Vit. B₆. Both vitamin C and vitamin B₉ increased absorbance due to hemolysis, indicating their stronger hemolytic effects. Among the 15 analyzed metal-vitamin combinations, 13 exhibited a Model Deviation Ratio (MDR) greater than 0.5, indicating an additive toxic effect. In contrast, three combinations showed an antagonistic effect, with the most significant interactions observed in Vit. B₉: Cu (MDR = 0.215), Vit. B₉: K (MDR = 0.48), and Vit. C: K (MDR = 0.4). Overall, this study highlights the complex interactions between heavy metals and vitamins in human erythrocytes and underscores the importance of understanding these relationships to mitigate heavy metal-induced toxicity.

Keywords: Heavy Metals, Hemolysis, MDR, Vitamin C, Vitamin B6, Vitamin B9.