1
Cardiovasc Hematol Agents Med Chem. 2010 Apr;8(2):113-27.
An evidence-based systematic review of stevia by the Natural Standard Research Collaboration.
Ulbricht C1, Isaac R, Milkin T, Poole EA, Rusie E, Grimes Serrano JM, Weissner W, Windsor RC, Woods J.
Abstract
The objective of this study was to evaluate the scientific evidence on stevia, including expert opinion, folkloric precedent, history, pharmacology, kinetics/dynamics, interactions, adverse effects, toxicology, and dosing. This review serves as a clinical support tool. Electronic searches were conducted in 10 databases, 20 additional journals (not indexed in common databases), and bibliographies from 50 selected secondary references. No restrictions were placed on the language or quality of the publications. All literature collected pertained to efficacy in humans, dosing, precautions, adverse effects, use in pregnancy and lactation, interactions, alteration of laboratory assays, and mechanisms of action. Standardized inclusion and exclusion criteria were used for selection. Grades were assigned using an evidence-based grading rationale. Based on the availability of scientific data, two indications are discussed in this review: hypertension and hyperglycemia. Evaluation of two long-term studies (1 and 2 years in length, respectively) indicates that stevia may be effective in lowering blood pressure in hypertensive patients, although data from shorter studies (1-3 months) did not support these findings. A pair of small studies also report positive results with respect to glucose tolerance and response, although the relatively low methodological rigor of these experiments limits the strength of these findings. Further investigation is warranted in both indications.
- PMID:
- 20370653
- [PubMed - indexed for MEDLINE]
2
- http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2900484/
- This study also had a number of strengths. First, both lean and obese individuals were included, increasing the generalizability of these findings. Second, food intake was directly measured, and satiety measurements were taken at identical time intervals as blood glucose and insulin levels. Third, a pilot study was initially conducted to determine the appropriate gram and calorie amounts to provide in the preloads. Moreover, all preloads were matched for gram weight, and the aspartame and stevia preloads were matched for caloric content.In conclusion, participants did not compensate by eating more at either their lunch or dinner meal and reported similar levels of satiety when they consumed lower calorie preloads containing stevia or aspartame than when they consumed higher calorie preloads containing sucrose. Additionally, stevia preloads reduced postprandial blood glucose and insulin levels, suggesting stevia may assist with glucose regulation. These effects appear to be independent of reductions in caloric intake, as participants consumed similar calorie amounts in both the stevia and aspartame conditions.
3.
- J Ethnopharmacol. 1999 Nov 1;67(2):157-61.
Effects of chronic administration of Stevia rebaudiana on fertility in rats.
Abstract
A study conducted on prepubertal male rats showed that chronic administration (60 days) of a Stevia rebaudiana aqueous extract produced a decrease in final weight of testis, seminal vesicle and cauda epididymidis. In addition, the fructose content of the accessory sex glands and the epididymal sperm concentration are decreased. Stevia treatment tended to decrease the plasma testosterone level, probably by a putative affinity of glycosides of extract for a certain androgen receptor, and no alteration occurred in luteinizing hormone level. These data are consistent with the possibility that Stevia extracts may decrease the fertility of male rats. 4.
Stevioside from Stevia rebaudiana Bertoni Increases Insulin Sensitivity in 3T3-L1 Adipocytes
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Abstract
Stevioside from Stevia rebaudiana has been reported to exert antihyperglycemic effects in both rat and human subjects. There have been few studies on these effects in vitro. In this paper, radioactive glucose uptake assay was implemented in order to assess improvements in insulin sensitivity in 3T3-L1 cells by elevation of glucose uptake following treatment with stevioside. Oil Red-O staining and MTT assay were utilized to confirm adipocyte differentiation and cell viability, respectively. Findings from this research showed a significant increase in absorbance values in mature adipocytes following Oil Red-O staining, confirming the differentiation process. Stevioside was noncytotoxic to 3T3-L1 cells as cell viability was reduced by a maximum of 17%, making it impossible to determine its IC50. Stevioside increased glucose uptake activities by 2.1 times (p < 0.001) in normal conditions and up to 4.4 times (p < 0.001) in insulin-resistant states. At times, this increase was higher than that seen in positive control group treated with rosiglitazone maleate, an antidiabetic agent. Expressions of pY20 and p-IRS1 which were measured via Western blot were improved by stevioside treatment. In conclusion, stevioside has direct effects on 3T3-L1 insulin sensitivity via increase in glucose uptake and enhanced expression of proteins involved in insulin-signalling pathway. 5.
Potential Roles of Stevia rebaudiana
- Evid Based Complement Alternat Med. 2013; 2013: 718049.Published online Nov 12, 2013. doi: 10.1155/2013/718049PMCID: PMC3845826
Potential Roles of Stevia rebaudiana Bertoni in Abrogating Insulin Resistance and Diabetes: A Review
Abstract
Insulin resistance is a key factor in metabolic disorders like hyperglycemia and hyperinsulinemia, which are promoted by obesity and may later lead to Type II diabetes mellitus. In recent years, researchers have identified links between insulin resistance and many noncommunicable illnesses other than diabetes. Hence, studying insulin resistance is of particular importance in unravelling the pathways employed by such diseases. In this review, mechanisms involving free fatty acids, adipocytokines such as TNFα and PPARγ and serine kinases like JNK and IKKβ, asserted to be responsible in the development of insulin resistance, will be discussed. Suggested mechanisms for actions in normal and disrupted states were also visualised in several manually constructed diagrams to capture an overall view of the insulin-signalling pathway and its related components. The underlying constituents of medicinal significance found in the Stevia rebaudiana Bertoni plant (among other plants that potentiate antihyperglycemic activities) were explored in further depth. Understanding these factors and their mechanisms may be essential for comprehending the progression of insulin resistance towards the development of diabetes mellitus.
5. Conclusion
Research in this field has established that the metabolic syndrome encompassing diabetes, obesity, and insulin resistance is highly correlated to various aspects, from the selection of a cell culture model through the understanding of each and every step in the mechanisms involved, with proper comprehension of the function of each component on the pathways. In order to counter the metabolic syndrome as a whole, it is essential to go through all the tiny details of each metabolic process. Even so, it is essential for researchers to look into the potential healing ability (bestowed on us by nature, but often well hidden) of diverse herbs and plants.It is postulated that the Stevia rebaudiana Bertoni plant could benefit the community medicinally through several different pathways, all eventually leading to its anti-hyperglycemic qualities. Although there are many unknowns and anomalies in our knowledge of insulin-signalling pathways, the mechanisms of glucose uptake, and the metabolic processes involved in insulin resistance, these loopholes could be addressed if researchers were to focus more on key factors such as IRS1, its phosphorylation, the translocation of GLUT4, and the roles of cytokines such as TNFα, not forgetting how PPARγ, JNK, and IKKβ contribute to insulin resistance.Potential Roles of Stevia rebaudiana
Potential Roles of Stevia rebaudiana
Potential Roles of Stevia rebaudiana
Potential Roles of Stevia rebaudiana
Potential Roles of Stevia rebaudiana
Evid Based Complement Alternat Med. 2013; 2013: 718049.Published online Nov 12, 2013. doi: 10.1155/2013/718049PMCID: PMC3845826Potential Roles of Stevia rebaudiana Bertoni in Abrogating Insulin Resistance and Diabetes: A Review
Abstract
Insulin resistance is a key factor in metabolic disorders like hyperglycemia and hyperinsulinemia, which are promoted by obesity and may later lead to Type II diabetes mellitus. In recent years, researchers have identified links between insulin resistance and many noncommunicable illnesses other than diabetes. Hence, studying insulin resistance is of particular importance in unravelling the pathways employed by such diseases. In this review, mechanisms involving free fatty acids, adipocytokines such as TNFα and PPARγ and serine kinases like JNK and IKKβ, asserted to be responsible in the development of insulin resistance, will be discussed. Suggested mechanisms for actions in normal and disrupted states were also visualised in several manually constructed diagrams to capture an overall view of the insulin-signalling pathway and its related components. The underlying constituents of medicinal significance found in the Stevia rebaudiana Bertoni plant (among other plants that potentiate antihyperglycemic activities) were explored in further depth. Understanding these factors and their mechanisms may be essential for comprehending the progression of insulin resistance towards the development of diabetes mellitus.
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