Antioxidant properties of Calendula officinalis L. (Asteraceae) on Fe2+-initiated peroxidation of rat brain mitochondria

In the study reported here, the effect of Calendula officinalis L. (Asteraceae) extract (CO) on the polyunsaturated fatty acid composition, chemiluminescence, and Peroxidizability Index (PI) of mitochondria isolated from brain rat was analyzed. After incubation of mitochondria in an ascorbate (0.4mM)-Fe++ (2.15 mu M) system (180min at 37 degrees C), it was observed that the total cpm/mg protein originated from light emission: chemiluminescence was lower in brain mitochondria obtained from CO group than in the control group (without extract supplementation). Moreover, it was observed that the extract was reduced, concentration dependent, of chemiluminescence, measured as total cpm. The fatty acid composition of brain mitochondria from control group was profoundly modified when subjected to non-enzymatic lipoperoxidation with a considerable decrease of arachidonic acid C20:46 and docosahexaenoic acid C22:63. As consequence, the PI, a parameter based on the maximal rate of oxidation of specific fatty acids was higher in the CO group than in the control group. The simultaneous analysis of PI, chemiluminescence, and fatty acid composition indicates that CO may act as an antioxidant protecting rat brain mitochondria from peroxidative damage.