Inhibitory Effects of Hot Water Extract of the Stevia Stem on the Contractile Response of the Smooth Muscle of the Guinea Pig Ileum

Steviol Glycosides from Stevia rebaudiana: An Updated Overview of Their Sweetening Activity, Pharmacological Properties, and Safety Aspects

This literature-based review synthesizes the available scientific information about steviol glycosides as natural sweeteners and molecules with therapeutic potential. In addition, it discusses the safety concerns regarding human consumption. Steviol glycosides exhibit a superior sweetener proficiency to that of sucrose and are noncaloric, noncariogenic, and nonfermentative. Scientific evidence encourages stevioside and rebaudioside A as sweetener alternatives to sucrose and supports their use based on their absences of harmful effects on human health. Moreover, these active compounds isolated from Stevia rebaudiana possess interesting medicinal activities, including antidiabetic, antihypertensive, anti-inflammatory, antioxidant, anticancer, and antidiarrheal activity. The described bioactivities of steviol glycosides deserve special attention based on their dose dependence and specific pathological situations. Further clinical research is needed to understand underlying mechanisms of action, therapeutic indexes, and pharmacological applications.

Prophylactic effect of aquatic extract of stevia on acetic acid induced-ulcerative colitis in male rats: a possible role of Nrf2 and PPARγ

Objectives Ulcerative colitis (UC) is a non-specific intestinal inflammatory disease. Several studies demonstrated that inflammation and oxidative stress play significant role in the pathogenesis of this disease. This study aimed to determine the protective effect and possible mechanism by which stevia affects the course of experimentally induced colitis. Methods Male rats were received stevia 20, 40, 80 mg/kg/day before induction of colitis by intra-rectal administration of 2 mL of 4% acetic acid, AA. Macroscopic and histopathological examination of the colon were done. Colonic content of catalase (CAT), superoxide dismutase (SOD), reduced glutathione (GSH), myeloperoxidase (MPO) and thiobarbituric acid reactive substances (TBARS) activities and serum levels of interleukin (IL)1- β and tumor necrosis factor (TNF)-α were assessed. Real time-PCR (RT-PCR) was done to determine the expression of NF-κB, Nrf2 and PPARγ genes. Spontaneous contraction and effects of increasing concentrations of acetylcholine and stevia have been studied on the isolated colonic segments. Results Stevia ameliorated colitis not only histopathologically but also it decreased the level of TNF-α, IL-1β, TBARS, MPO and the expression of NF-κB which were significantly increased in the AA group. The concentration of GSH, SOD, CAT and expression of Nrf2 and PPARγ were significantly increased with stevia. Moreover, stevia showed a relaxant effect on the colonic contractility which was increased in AA group. These all effects of stevia were more prominent with its highest dose. Conclusion Our results explored that, stevia acts protectively against UC by its anti-inflammatory and antioxidant properties which mediated by up-regulation of Nrf2 and PPARγ with downregulation of NF-κB. We suggest that stevia has the potential for treatment of chronic inflammatory diseases, such as UC.

Stevia as a Natural Sweetener: A Review

Stevia rebaudiana of the Asteraceae family is a perennial shrub. It is a sweetener herb also known as sweet weed, sweet leaf, sweet herbs and honey leaf, native to Argentina, Brazil and Paraguay. The leaves of stevia are sweeter than sucrose with zero calories. Steviol, a diterpenoid glycoside derivative identified from this plant, is sweeter than sucrose and is safe when used as a sweetening agent. Diabetic and obese people with hyperglycemia who are in a condition to follow a strict diet can use stevioside as an alternative sweetener. In addition to its hypoglycemic property, the plant also exhibits antibacterial, anti-inflammatory, hypotensive, antiseptic, diuretic, anti-fertility and cardiotonic properties. It has also been documented to show good effects on treating skin diseases such as dermatitis, acne, eczema etc. The leaves of stevia with enriched phytoconstituents could be an alternative natural sweetener for children, adults and old age persons who have a craze to drink beverages and eat sweetened food products in their habitual life.

Stevia rebaudiana Bertoni bioactive effects: From in vivo to clinical trials towards future therapeutic approaches

Stevia rebaudiana Bertoni, a plant from South America and indigenous of Paraguay, has shown several biological effects and healthy properties, although it is especially used in South America and some Asiatic regions. In addition, it is a natural sweetener, almost 300 times sweeter than sucrose, being attributed to its phytoconstituents prominent antioxidant, antimicrobial, antidiabetic (antihyperglycemic, insulinotropic, and glucagonostatic), antiplatelet, anticariogenic, and antitumor effects. In this sense, this work aims to provide an extensive overview on the historical practices of stevia and its effects in human health based on its chemical composition and applications for both food and pharmaceutical industries.

Natural sweeteners: health benefits of stevia

Stevia rebaudiana (Bertoni), a perennial shrub, is the sweetest plant belonging to the Asteraceae family. Stevia leaves are an excellent source of diterpene glycosides stevioside, rebaudioside A-F, dulcoside, and steviolbioside, which are responsible for sweetness and have been utilized commercially for sugar substitution in foods, beverages, and medicines. To the best of our knowledge, a large number of studies have been carried out on composition, health implications, and safety of steviol glycosides. However, commercial production of stevia-incorporated food products needs further research in order to meet the huge global demand. Stevia-incorporated products possess better sweetening potency and maximum consumer acceptability, when compared with other sugar substitutes. Hence, the current research attempts to review the health promoting effects of stevia with special emphasis on its application in the food system. The paper majorly features 1) the anti-hyperglycemic, anti-hypertensive, anti-caries, anti-inflammatory, and anti-cancer benefits of stevia, 2) value-added stevia-incorporated products, e.g. bakery, dairy, and beverages, 3) the effect of incorporation of stevia on physicochemical, rheological, and nutritional food properties, 4) the current status and regulatory perspective of utilizing stevia at national and international level. Due to legislative actions and growing consumer awareness, public interest in natural sweeteners has significantly increased. Since the use of artificial sweetener has recently been questioned, the data the present article provides will be useful for consumers and manufacturers that seek an alternative.

Is Stevia rebaudiana Bertoni a Non Cariogenic Sweetener? A Review

Stevia rebaudiana Bertoni is a small perennial shrub of the Asteraceae (Compositae) family that is native to South America, particularly Brazil and Paraguay, where it is known as "stevia" or "honey leaf" for its powerful sweetness. Several studies have suggested that in addition to their sweetness, steviosides and their related compounds, including rebaudioside A and isosteviol, may offer additional therapeutic benefits. These benefits include anti-hyperglycaemic, anti-hypertensive, anti-inflammatory, anti-tumor, anti-diarrheal, diuretic, and immunomodulatory actions. Additionally, critical analysis of the literature supports the anti-bacterial role of steviosides on oral bacteria flora. The aim of this review is to show the emerging results regarding the anti-cariogenic properties of S. rebaudiana Bertoni. Data shown in the present paper provide evidence that stevioside extracts from S. rebaudiana are not cariogenic. Future research should be focused on in vivo studies to evaluate the effects on dental caries of regular consumption of S. rebaudiana extract-based products.

Stevioside and related compounds: therapeutic benefits beyond sweetness

Stevioside, an abundant component of Stevia rebaudiana leaf, has become well-known for its intense sweetness (250-300 times sweeter than sucrose) and is used as a non-caloric sweetener in several countries. A number of studies have suggested that, beside sweetness, stevioside along with related compounds, which include rebaudioside A (second most abundant component of S. rebaudiana leaf), steviol and isosteviol (metabolic components of stevioside) may also offer therapeutic benefits, as they have anti-hyperglycemic, anti-hypertensive, anti-inflammatory, anti-tumor, anti-diarrheal, diuretic, and immunomodulatory actions. It is of interest to note that their effects on plasma glucose level and blood pressure are only observed when these parameters are higher than normal. As steviol can interact with drug transporters, its role as a drug modulator is proposed. This review summarizes the current knowledge of the pharmacological actions, therapeutic applications, pharmacokinetics and safety of stevioside and related compounds. Although much progress has been made concerning their biological and pharmacological effects, questions regarding chemical purity and safety remain unsolved. These issues are discussed to help guide future research directions.