Digestive Enzyme Activities, Oxidative Status and Intestinal Histomorphometry of Rats Supplemented with Steviana, A Natural Sweetener.

Abstract

<b>Background and Objective:</b> Stevia (<i>Stevia rebaudiana</i>), often known as sweet leaf, is a perennial plant and a member of the Asteraceae family. The commercial version of stevia leaf powder, known as Steviana, is one of the most popular natural sweeteners in use today. The current study aimed to analyze the activities of gut digestive enzymes, intestinal oxidative state and intestinal histological structure in stevia-fed rats. <b>Materials and Methods:</b> In this study, male rats were given Steviana and the oxidative condition of the gastrointestinal tract (GIT), the activities of certain digestive enzymes and the histomorphology of the GIT were examined. Animals used in experiments were split into 2 groups: Control and treated groups. For four consecutive weeks, the treatment group received a daily oral intake of 5 mg kg<sup>1</sup> b.wt., of Steviana solution. At the end of the trial, serum, pancreas and intestinal tissue samples were taken. <b>Results:</b> The Steviana sweetener has a strong antioxidative effect on both blood and intestinal tissue. Both sample types showed a decrease in malondialdehyde levels and a marked increase in superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities compared to control samples. In samples of blood, pancreas and intestinal contents, the activities of digestive enzymes including α-amylase, lipase and protease were significantly elevated in Steviana-treated rats. In addition, histological analysis of the small intestine showed that in rats given Steviana sweetener, intestinal glandular crypt depth was more pronounced compared to the control animals. <b>Conclusion:</b> In summary, consumption of Steviana appears to enhance digestion and absorption processes through antioxidative effects, improving the health of the local GIT and subsequently accelerating the rate of synthesis and release of endogenous digestive enzymes. Another aspect that enhances the digestion and absorption process is the change in the histological structure of the intestinal glands, as shown by an increase in the crypt depth.