Ok, Sle, I did. And you know what? It didn't say that stevia "improves insulin sensitivity", nor did it say anything about "have much of any insulin secretion." Are you just making this stuff up? If not, perhaps you could be more specific.
-- Rick
No idea what you were looking for exactly but for your comfort here are a few tidbits.
-
Stevioside acts directly on pancreatic beta cells to secrete insulin:
actions independent of cyclic adenosine monophosphate and adenosine
triphosphate-sensitive K+-channel activity.
Jeppesen PB, Gregersen S, Poulsen CR, Hermansen K.
Department of Endocrinology and Metabolism, Aarhus University Hospital,
Denmark.
The natural sweetener stevioside, which is found in the plant Stevia
rebaudiana Bertoni, has been used for many years in the treatment of
diabetes among Indians in Paraguay and Brazil. However, the mechanism
for the blood glucose-lowering effect remains unknown. To elucidate the
impact of stevioside and its aglucon steviol on insulin release from
normal mouse islets and the beta-cell line INS-1 were used. Both
stevioside and steviol (1 nmol/L to 1 mmol/L) dose-dependently enhanced
insulin secretion from incubated mouse islets in the presence of 16.7
mmol/L glucose (P < .05). The insulinotropic effects of stevioside and
steviol were critically dependent on the prevailing glucose
concentration, ie, stevioside (1 mmol/L) and steviol (1 micromol/L) only
potentiated insulin secretion at or above 8.3 mmol/L glucose (P < .05).
Interestingly, the insulinotropic effects of both stevioside and steviol
were preserved in the absence of extracellular Ca2+. During perifusion
of islets, stevioside (1 mmol/L) and steviol (1 micromol/L) had a
long-lasting and apparently reversible insulinotropic effect in the
presence of 16.7 mmol/L glucose (P < .05). To determine if stevioside
and steviol act directly on beta cells, the effects on INS-1 cells were
also investigated. Stevioside and steviol both potentiated insulin
secretion from INS-1 cells (P < .05). Neither stevioside (1 to 100
micromol/L) nor steviol (10 nmol/L to 10 micromol/L) influenced the
plasma membrane K+ adenosine triphosphate ((K+)ATP)-sensitive channel
activity, nor did they alter cyclic adenosine monophosphate (cAMP)
levels in islets. In conclusion, stevioside and steviol stimulate
insulin secretion via a direct action on beta cells. The results
indicate that the compounds may have a potential role as
antihyperglycemic agents in the treatment of type 2 diabetes mellitus.
PMID: 10690946 [PubMed - indexed for MEDLINE]
-
Small study in Denmark on "Twelve type 2 diabetic patients were included
in an acute, paired cross-over study."
Stevioside acts directly on pancreatic beta cells to secrete insulin:
actions independent of cyclic adenosine monophosphate and adenosine
triphosphate-sensitive K+-channel activity.
"In conclusion, stevioside and steviol stimulate insulin secretion via a
direct action on beta cells. The results indicate that the compounds may
have a potential role as antihyperglycemic agents in the treatment of
type 2 diabetes mellitus."
Geuns JM
Laboratory of Plant Physiology, Catholic University of Leuven,
Kasteelpark Arenberg 31, B 3001 Leuven, Belgium
"The conclusion is that Stevia and stevioside are safe when used as a
sweetener. It is suited for both diabetics, and PKU patients, as well as
for obese persons intending to lose weight by avoiding sugar supplements
in the diet. No allergic reactions to it seem to exist."
Phytomedicine 2002 Jan; 9(1): 9-14 (ISSN: 0944-7113)
Study in Denmark on rats.
"In conclusion, stevioside exerts antihyperglycaemic, insulinotropic,
and glucagonostatic actions in the type 2 diabetic GK rat, and may have
the potential of becoming a new antidiabetic drug for use in type 2
diabetes."
Clin Ther 2003 Nov; 25(11): 2797-808 (ISSN: 0149-2918)
This study was undertaken to investigate the long-term (2-year) efficacy
and tolerability of stevioside in patients with mild essential
hypertension.
This was a multicenter, randomized, double-blind, placebo-controlled
trial in Chinese men and women aged between 20 and 75 years with mild
essential hypertension (systolic blood pressure [SBP] 140-159 mm Hg and
diastolic blood pressure [DBP] 90-99 mm Hg). Patients took capsules
containing 500 mg stevioside powder or placebo 3 times daily for 2 years
"after 2 years, 6 of 52 patients (11.5%) in the stevioside group had
left ventricular hypertrophy (LVH), compared with 17 of 50 patients
(34.0%) in the placebo group (P < 0.001). Of those who did not have LVH
at baseline, 3 of 46 patients (6.5%) in the stevioside group had
developed LVH after 2 years, compared with 9 of 37 patients (24.3%) in
the placebo group (P < 0.001).
CONCLUSIONS: In this 2-year study in
Chinese patients with mild hypertension, oral stevioside significantly
decreased SBP and DBP compared with placebo. QOL was improved, and no
significant adverse effects were noted."
-
Metabolism. 2004 Jan;53(1):73-6. Related Articles, Links
Antihyperglycemic effects of stevioside in type 2 diabetic subjects.
Gregersen S, Jeppesen PB, Holst JJ, Hermansen K.
Department of Endocrinology and Metabolism C, Aarhus University
Hospital, Denmark.
Stevioside is present in the plant Stevia rebaudiana Bertoni (SrB).
Extracts of SrB have been used for the treatment of diabetes in, for
example, Brazil, although a positive effect on glucose metabolism has
not been unequivocally demonstrated. We studied the acute effects of
stevioside in type 2 diabetic patients. We hypothesize that
supplementation with stevioside to a test meal causes a reduction in
postprandial blood glucose. Twelve type 2 diabetic patients were
included in an acute, paired cross-over study. A standard test meal was
supplemented with either 1 g of stevioside or 1 g of maize starch
(control). Blood samples were drawn at 30 minutes before and for 240
minutes after ingestion of the test meal. Compared to control,
stevioside reduced the incremental area under the glucose response
curve by 18% (P =.013). The insulinogenic index
(AUC(i,insulin)/AUC(i,glucose)) was increased by approximately 40% by
stevioside compared to control (P <.001). Stevioside tended to decrease
glucagon levels, while it did not significantly alter the area under
the insulin, glucagon-like peptide 1, and glucose-dependent
insulinotropic polypeptide curves. In conclusion, stevioside reduces
postprandial blood glucose levels in type 2 diabetic patients,
indicating beneficial effects on the glucose metabolism. Stevioside may
be advantageous in the treatment of type 2 diabetes.
Publication Types:
Clinical Trial
Randomized Controlled Trial
PMID: 14681845 [PubMed - indexed for MEDLINE]
-
Effect of Stevia rebaudiana on glucose tolerance in normal adult
humans.
Curi R, Alvarez M, Bazotte RB, Botion LM, Godoy JL, Bracht A.
Departamento de Farmacia-Bioquimica, Universidade de Maringa, Brasil.
The effect of aqueous extracts of Stevia rebaudiana leaves on a glucose
tolerance test was investigated in 16 normal volunteers. Aqueous
extracts of 5 grams of leaves were administered to volunteers at
regular 6-h intervals for 3 days. Glucose tolerance tests were
performed before and after extract administration. A second group of 6
normal volunteers who ingested an aqueous arabinose solution was also
studied to eliminate possible stress effects. The extract of Stevia
rebaudiana increased glucose tolerance. The extract significantly
decreased plasma glucose levels during the test and after overnight
fasting in all volunteers.
PMID: 3651629 [PubMed - indexed for MEDLINE]
-
Stevioside acts directly on pancreatic beta cells to secrete insulin:
actions independent of cyclic adenosine monophosphate and adenosine
triphosphate-sensitive K+-channel activity.
Jeppesen PB, Gregersen S, Poulsen CR, Hermansen K.
Department of Endocrinology and Metabolism, Aarhus University Hospital,
Denmark.
The natural sweetener stevioside, which is found in the plant Stevia
rebaudiana Bertoni, has been used for many years in the treatment of
diabetes among Indians in Paraguay and Brazil. However, the mechanism
for the blood glucose-lowering effect remains unknown. To elucidate the
impact of stevioside and its aglucon steviol on insulin release from
normal mouse islets and the beta-cell line INS-1 were used. Both
stevioside and steviol (1 nmol/L to 1 mmol/L) dose-dependently enhanced
insulin secretion from incubated mouse islets in the presence of 16.7
mmol/L glucose (P < .05). The insulinotropic effects of stevioside and
steviol were critically dependent on the prevailing glucose
concentration, ie, stevioside (1 mmol/L) and steviol (1 micromol/L) only
potentiated insulin secretion at or above 8.3 mmol/L glucose (P < .05).
Interestingly, the insulinotropic effects of both stevioside and steviol
were preserved in the absence of extracellular Ca2+. During perifusion
of islets, stevioside (1 mmol/L) and steviol (1 micromol/L) had a
long-lasting and apparently reversible insulinotropic effect in the
presence of 16.7 mmol/L glucose (P < .05). To determine if stevioside
and steviol act directly on beta cells, the effects on INS-1 cells were
also investigated. Stevioside and steviol both potentiated insulin
secretion from INS-1 cells (P < .05). Neither stevioside (1 to 100
micromol/L) nor steviol (10 nmol/L to 10 micromol/L) influenced the
plasma membrane K+ adenosine triphosphate ((K+)ATP)-sensitive channel
activity, nor did they alter cyclic adenosine monophosphate (cAMP)
levels in islets. In conclusion, stevioside and steviol stimulate
insulin secretion via a direct action on beta cells. The results
indicate that the compounds may have a potential role as
antihyperglycemic agents in the treatment of type 2 diabetes mellitus.
PMID: 10690946 [PubMed - indexed for MEDLINE]