Comparative analysis of BPA and HQ toxic impacts on human erythrocytes, protective effect mechanism of tannins (Rhus typhina)

Abstract

Several studies reported that bisphenol A (BPA) and its metabolite hydroquinone (HQ) have adverse effects on human and animal health. In this work, a comparative study of influence of the BPA and HQ, environment pollutants, on human erythrocytes was carried out. It was shown that BPA and HQ to varying extents caused oxidative damage in human erythrocytes: hemolysis, decreased GSH level, and methemoglobin formation. It was demonstrated that hydrolysable tannins 3,6-bis-O-di-O-galloyl-1,2,4-tri-O-galloyl-β-D-glucose (C₅₅H₄₀O₃₄) and 1,2,3,4,6-penta-O-galloyl-β-D-glucose (C₄₁H₃₂O₂₆) (PGG) isolated from the Rhus typhina L. leaves in the range of 1-50 μM concentrations inhibited hemolysis and methemoglobin formation and also increased intracellular reduced glutathione in erythrocytes treated with BPA or HQ. It was revealed by electron paramagnetic resonance (EPR) using 5-doxyl-stearic acid (5-DS) that C₅₅H₄₀O₃₄ and C₄₁H₃₂O₂₆ increased the rigidity of erythrocyte membranes at the depth of 5th carbon atom of the fatty acid hydrocarbon chain. Taken together, these results allow to conclude that tannins from the Rhus typhina L. leaves protect erythrocytes from oxidative stress caused by BPA or HQ both due to their antioxidant activity as well as their interaction with the erythrocyte membrane components.

Keywords: Bisphenol A; EPR; Erythrocytes; Glutathione; Hemolysis; Hydroquinone; Membrane fluidity; Methemoglobin; Rhus; Tannins.

Fig. 1

Chemical structure of 3,6-bis-O-di-O-galloyl-1,2,4-tri-O-galloyl-β-d-glucose (C₅₅H₄₀O₃₄) (a), 1,2,3,4,6-penta-O-galloyl-β-d-glucose (C₄₁H₃₂O₂₆) (PGG) (b), bisphenol A (BPA) (c), and hydroquinone (HQ) (d)

Fig. 2

Protective effect of C₅₅H₄₀O₃₄ and C₄₁H₃₂O₂₆ against formation of methemoglobin in erythrocytes induced by 200 μg/mL BPA (a) or HQ (b). The data presented as the means ± SE (n = 10). The effects of compounds were statistically significant according to one-way ANOVA test (*p < 0.05; **p < 0.01; ***p < 0.001)

Fig. 3

Sparing effect of C₅₅H₄₀O₃₄ and C₄₁H₃₂O₂₆ on GSH depletion in erythrocytes induced by 200 μg/mL BPA (a) or 50 μg/mL HQ (b). The data presented are the means ± SE (n = 10). The effects of compounds were statistically significant according to one-way ANOVA test (*p < 0.05; **p < 0.01; ***p < 0.001)

Fig. 4

Protective effect of C₅₅H₄₀O₃₄ and C₄₁H₃₂O₂₆ against hemolysis induced by 200 μg/mL BPA (a) or HQ (b). The data are presented as means ± SE (n = 10). The effects of compounds were statistically significant according to one-way ANOVA test (*p < 0.05; **p < 0.01; ***p < 0.001)

Fig. 5

The EPR spectrum of erythrocytes labeled with 5-DS—control (a), C₅₅H₄₀O₃₄ (b), and C₄₁H₃₂O₂₆ (c)

Fig. 6

The effect of C₅₅H₄₀O₃₄ and C₄₁H₃₂O₂₆ on the order parameter S/S ₀ (a) and the rotational correlation time (τ _c) (b) of the probe 5-DS in erythrocytes. The data presented are the means ± SE (n = 10). The effects of compounds were statistically significant according to one-way ANOVA test (*p < 0.05; **p < 0.01; ***p < 0.001)