Consumption of plant polyphenols has been reported to confer a variety of health benefits, including reduced cancer risk and coronary heart disease mortality. Oxidative damage is associated with the pathological development in the cardiovascular system, and flavonoids, a class of polyphenolics, are known to have antioxidant activity against a range of free radicals. Quercetin (Q) is a flavonoid that is commonly found in vegetables and plants. It can be used in co-treatment and as a supplement in many diseases, such as ischemic heart disease, atherosclerosis, liver fibrosis, and kidney failure. Erythrocytes are frequently used as a biological model to assess the hemolytic, anti-hemolytic, and antioxidant potential of various compounds because their membranes are rich in polyunsaturated fatty acids, making them highly sensitive to oxidative stress. Furthermore, erythrocytes are the first targets of free radical attack due to their potential to generate reactive oxygen species (ROS) and the redox reactions of hemoglobin associated with oxygen transfer. In the present case, the in vitro hemolytic activity of quercetin was evaluated on human red blood cells (RBC). Antioxidant activity of quercetin was measured by neutralizing DPPH and ABTS radicals. Quercetin showed hemocompatibility at concentrations below 80 μg/mL, whereas acceptable hemolysis limits are less than 3.9%. The highest concentration (500 μg/mL) treatment caused 8.3% hemolysis. In both antioxidant DPPH and ABTS assays, IC50 values were 0.598 μg/mL and 0.415 μg/mL, respectively. The results of this study indicated that hemocompatibility was attributed to quercetin's antioxidant status, which protected erythrocytes from oxidative damage and hemolysis.
Janić et al. (Wed,) studied this question.