Protective effects of selected medicinal plants against protein degradation, lipid peroxidation and deformability loss of oxidatively stressed human erythrocytes.

The effects of seven medicinal plants including Artemisia herba-alba, Ferula hermonis, Hibiscus sabdariffa, Nigella sativa, Teucrium polium, Trigonella foenum-graecum, and Allium sativum on protein degradation, lipid peroxidation, erythrocyte deformability and osmotic fragility of erythrocytes exposed in vitro to 10 mM H(2)O(2) for 60 min at 37 degrees C have been examined. Preincubation of erythrocytes with Nigella sativa and Allium sativum protected erythrocytes against protein degradation, loss of deformability and increased osmotic fragility caused by H(2)O(2), while the other plants failed to protect erythrocytes against these damages. Artemisia herba-alba did not protect erythrocytes against lipid peroxidation, while Trigonella foenum-graecum unexpectedly increased lipid peroxidation of erythrocytes exposed to H(2)O(2). Ferula hermonis, Hibiscus sabdariffa, Nigella sativa, Teucrium polium and Allium sativum protected erythrocytes against lipid peroxidation. The results indicate the importance of oxidatively damaged cellular proteins in compromising the rheologic behaviour of the erythrocytes, and that the medicinal plants which have anti-protein-oxidant activity (e.g. Nigella sativa and Allium sativum) could be rheologically useful, particularly in pathological conditions related to free radicals.