Comparison of Steviol Glycosides or Stevia Leaves Addition to the Hypercholesterolemic Diet on Selected Biochemical Parameters of Experimental Rats

Stevia rebaudiana, as a plant with favorable technological features, and, above all, with potential health-promoting properties, seems to be an ideal sugar substitute. The aim of this study was to compare the effect of adding pure steviol glycosides or Stevia leaves to a hypercholesterolemic diet on selected growth and biochemical parameters of experimental (non-diabetes) rats. The research material consisted of dried leaves of Stevia (Stevia rebaudiana Bertoni, Polish, Brazilian and Paraguayan origin) and steviol glycosides (GS). In the animal experiment, young male Wistar rats were used. The animals were divided into six experimental groups, six rats per group, and placed in individual metabolic cages, provided with drinking bowls and feeders. The animals from particular groups received a semi-synthetic AIN-93G diet for growing rats or its modification (group I-AIN-93G diet; group II-hypercholesterolemic diet; group III-hypercholesterolemic diet with 0.28 g of GS/kg of diet; group IV; V; VI-hypercholesterolemic diet with dried Stevia leaves addition from Polish (PL), Brazilian (BR) and Paraguayan (PR) cultivation) in amounts providing GS as in group III, i.e., 10, 17 and 18%, respectively. The addition of GS to the hypercholesterolemic diet resulted only in a tendency to lower the weight of the kidneys, heart and liver compared to animals fed with the hypercholesterolemic diet. The lowest glucose concentration was found in animals receiving the 17%BR diet. In general, all lipid profile parameters were similar or increased in rats fed the hypercholesterolemic diet with the addition of steviol glycosides and Stevia leaves, respectively. The highest antioxidant activity was recorded in the blood serum of rats fed the hypercholesterolemic diet with 10%PL dried Stevia leaves addition.