scholarly journals Insulin secretory effect of sitagliptin: assessment with a hyperglycemic clamp combined with a meal challenge

2018 ◽  
Vol 314 (4) ◽  
pp. E406-E412
Author(s):  
Sudha S. Shankar ◽  
R. Ravi Shankar ◽  
Lori A. Mixson ◽  
Deborah L. Miller ◽  
Helmut O. Steinberg ◽  
...  

Sitagliptin, a dipeptidyl peptidase-IV inhibitor (DPP-4), sustains activity of the incretin hormones GLP-1 and GIP and improves hyperglycemia in Type 2 diabetes mellitus (T2DM). It has however proven challenging to quantify the effect of sitagliptin on rates of insulin secretion (ISR) during a prandial challenge. The tight feedback governance of ISR by plasma glucose means that in the face of treatment-related lowering of postprandial glycemia, corresponding stimulation of ISR is lessened. We postulated that sustaining a stable level of moderate hyperglycemia before and during a meal challenge (MC) would be a platform that enables greater clarity to assess the effect of sitagliptin on ISR and an approach that could be valuable to evaluate novel targets that increase insulin secretion directly and by augmenting incretins. A hyperglycemic clamp (HGC) at 160 mg/dl was conducted in 12 healthy volunteers (without diabetes) for 6 h; 3 h into the HGC, MC was administered while maintaining stable hyperglycemia of the HGC for an additional 3 h. Modeling of C-peptide response was used to calculate ISR. In crossover design of three periods (sitagliptin twice and placebo once), the effect of sitagliptin vs. placebo on ISR and the reproducibility of the response to sitagliptin were assessed. Sitagliptin increased ISR compared with placebo by 50% and 20% during the HGC alone and the HGC-MC phases, respectively ( P < 0.001 for both). There was an associated significant treatment-based increase in circulating insulin, as well as active levels of GLP-1. Robust reproducibility of the sitagliptin-mediated ISR response was observed; the intraclass correlation value was 0.94. The findings delineate the effect of sitagliptin to stimulate insulin secretion, and these benchmark data also demonstrate that an HGC-MC can be a useful platform for interrogating therapeutic targets that could potentially modulate ISR via direct action on beta-cells as well as by augmenting release or action of incretins.

2016 ◽  
Vol 311 (2) ◽  
pp. E461-E470 ◽  
Author(s):  
Rachel J. Perry ◽  
Rebecca L. Cardone ◽  
Max C. Petersen ◽  
Dongyan Zhang ◽  
Pascale Fouqueray ◽  
...  

Imeglimin is a promising new oral antihyperglycemic agent that has been studied in clinical trials as a possible monotherapy or add-on therapy to lower fasting plasma glucose and improve hemoglobin A1c (1–3, 9). Imeglimin was shown to improve both fasting and postprandial glycemia and to increase insulin secretion in response to glucose during a hyperglycemic clamp after 1-wk of treatment in type 2 diabetic patients. However, whether the β-cell stimulatory effect of imeglimin is solely or partially responsible for its effects on glycemia remains to be fully confirmed. Here, we show that imeglimin directly activates β-cell insulin secretion in awake rodents without affecting hepatic insulin sensitivity, body composition, or energy expenditure. These data identify a primary amplification rather than trigger the β-cell mechanism that explains the acute, antidiabetic activity of imeglimin.


2007 ◽  
Vol 292 (6) ◽  
pp. E1775-E1781 ◽  
Author(s):  
Kenneth Cusi ◽  
Sangeeta Kashyap ◽  
Amalia Gastaldelli ◽  
Mandeep Bajaj ◽  
Eugenio Cersosimo

Elevated plasma FFA cause β-cell lipotoxicity and impair insulin secretion in nondiabetic subjects predisposed to type 2 diabetes mellitus [T2DM; i.e., with a strong family history of T2DM (FH+)] but not in nondiabetic subjects without a family history of T2DM. To determine whether lowering plasma FFA with acipimox, an antilipolytic nicotinic acid derivative, may enhance insulin secretion, nine FH+ volunteers were admitted twice and received in random order either acipimox or placebo (double-blind) for 48 h. Plasma glucose/insulin/C-peptide concentrations were measured from 0800 to 2400. On day 3, insulin secretion rates (ISRs) were assessed during a +125 mg/dl hyperglycemic clamp. Acipimox reduced 48-h plasma FFA by 36% ( P < 0.001) and increased the plasma C-peptide relative to the plasma glucose concentration or ΔC-peptide/Δglucose AUC (+177%, P = 0.02), an index of improved β-cell function. Acipimox improved insulin sensitivity (M/I) 26.1 ± 5% ( P < 0.04). First- (+19 ± 6%, P = 0.1) and second-phase (+31 ± 6%, P = 0.05) ISRs during the hyperglycemic clamp also improved. This was particularly evident when examined relative to the prevailing insulin resistance [1/(M/I)], as both first- and second-phase ISR markedly increased by 29 ± 7 ( P < 0.05) and 41 ± 8% ( P = 0.02). There was an inverse correlation between fasting FFA and first-phase ISR ( r2 = 0.31, P < 0.02) and acute (2–4 min) glucose-induced insulin release after acipimox ( r2 =0.52, P < 0.04). In this proof-of-concept study in FH+ individuals predisposed to T2DM, a 48-h reduction of plasma FFA improves day-long meal and glucose-stimulated insulin secretion. These results provide additional evidence for the important role that plasma FFA play regarding insulin secretion in FH+ subjects predisposed to T2DM.


2007 ◽  
Vol 66 (3) ◽  
pp. 451-457 ◽  
Author(s):  
D. B. Dunger ◽  
B. Salgin ◽  
K. K. Ong

Size at birth and patterns of postnatal weight gain have been associated with adult risk for the development of type 2 diabetes in many populations, but the putative pathophysiological link remains unknown. Studies of contemporary populations indicate that rapid infancy weight gain, which may follow fetal growth restriction, is an important risk factor for the development of childhood obesity and insulin resistance. Data from the Avon Longitudinal Study of Pregnancy and Childhood shows that rapid catch-up weight gain can lead to the development of insulin resistance, as early as 1 year of age, in association with increasing accumulation of central abdominal fat mass. In contrast, the disposition index, which reflects the β-cells ability to maintain insulin secretion in the face of increasing insulin resistance, is much more closely related to ponderal index at birth than postnatal catch-up weight gain. Infants with the lowest ponderal index at birth show a reduced disposition index at aged 8 years associated with increases in fasting NEFA levels. The disposition index is also closely related to childhood height gain and insulin-like growth factor-I (IGF-I) levels; reduced insulin secretory capacity being associated with reduced statural growth, and relatively short stature with reduced IGF-I levels at age 8 years. IGF-I may have an important role in the maintenance of β-cell mass, as demonstrated by recent studies of pancreatic β-cell IGF-I receptor knock-out and adult observational studies indicating that low IGF-I levels are predictive of subsequent risk for the development of type 2 diabetes. However, as insulin secretion is an important determinant of IGF-I levels, cause and effect may be difficult to establish. In conclusion, although rapid infancy weight gain and increasing rates of childhood obesity will increase the risk for the development of insulin resistance, prenatal and postnatal determinants of β-cell mass may ultimately be the most important determinants of an individual's ability to maintain insulin secretion in the face of increasing insulin resistance, and thus risk for the development of type 2 diabetes.


2003 ◽  
Vol 284 (1) ◽  
pp. E129-E137 ◽  
Author(s):  
Elisabeth Qvigstad ◽  
Ingrid L. Mostad ◽  
Kristian S. Bjerve ◽  
Valdemar E. Grill

We tested the effects of acute perturbations of elevated fatty acids (FA) on insulin secretion in type 2 diabetes. Twenty-one type 2 diabetes subjects with hypertriglyceridemia (triacylglycerol >2.2 mmol/l) and 10 age-matched nondiabetic subjects participated. Glucose-stimulated insulin secretion was monitored during hyperglycemic clamps for 120 min. An infusion of Intralipid and heparin was added during minutes 60–120. In one of two tests, the subjects ingested 250 mg of Acipimox 60 min before the hyperglycemic clamp. A third test (also with Acipimox) was performed in 17 of the diabetic subjects after 3 days of a low-fat diet. Acipimox lowered FA levels and enhanced insulin sensitivity in nondiabetic and diabetic subjects alike. Acipimox administration failed to affect insulin secretion rates in nondiabetic subjects and in the group of diabetic subjects as a whole. However, in the diabetic subjects, Acipimox increased integrated insulin secretion rates during minutes 60–120 in the 50% having the lowest levels of hemoglobin A1c (379 ± 34 vs. 326 ± 30 pmol · kg−1 · min−1without Acipimox, P < 0.05). A 3-day dietary intervention diminished energy from fat from 39 to 23% without affecting FA levels and without improving the insulin response during clamps. Elevated FA levels may tonically inhibit stimulated insulin secretion in a subset of type 2 diabetic subjects.


2008 ◽  
Vol 93 (7) ◽  
pp. 2633-2638 ◽  
Author(s):  
G. Nijpels ◽  
W. Boorsma ◽  
J. M. Dekker ◽  
F. Hoeksema ◽  
P. J. Kostense ◽  
...  

Abstract Context: In persons with impaired glucose tolerance (IGT), both impaired insulin secretion and insulin resistance contribute to the conversion to type 2 diabetes mellitus (T2DM). However, few studies have used criterion standard measures to asses the predictive value of impaired insulin secretion and insulin resistance for the conversion to T2DM in a Caucasian IGT population. Objectives: The objective of the study was to determine the predictive value of measures of insulin secretion and insulin resistance derived from a hyperglycemic clamp, including the disposition index, for the development of T2DM in a Caucasian IGT population. Design, Setting, and Participants: The population-based Hoorn IGT study consisted of 101 Dutch IGT subjects (aged &lt; 75 yr), with mean 2-h plasma glucose values, of two separate oral glucose tolerance tests, between 8.6 and 11.1 mmol/liter. A hyperglycemic clamp at baseline was performed to assess first-phase and second-phase insulin secretion and insulin sensitivity. During follow-up, conversion to T2DM was assessed by means of 6-monthly fasting glucose levels and yearly oral glucose tolerance tests. Results: The cumulative incidence of T2DM was 34.7%. Hazard ratio for T2DM development adjusted for age, sex, and body mass index was 5.74 [95% confidence interval (CI) 2.60–12.67] for absence of first insulin peak, 1.58 (95% CI 0.60–4.17) for lowest vs. highest tertile of insulin sensitivity, and 1.78 (95% CI 0.65–4.88) for lowest vs. highest tertile of the disposition index. Conclusions: In these Caucasian persons with IGT, the absence of the first insulin peak was the strongest predictor of T2DM.


2018 ◽  
Vol 103 (12) ◽  
pp. 4373-4383 ◽  
Author(s):  
Felicia Gerst ◽  
Benjamin A Jaghutriz ◽  
Harald Staiger ◽  
Anke M Schulte ◽  
Estela Lorza-Gil ◽  
...  

Abstract Context Reduced β-cell mass, impaired islet function, and dedifferentiation are considered causal to development of hyperglycemia and type 2 diabetes. In human cohort studies, changes of islet cell–specific expression patterns have been associated with diabetes but not directly with in vivo insulin secretion. Objective This study investigates alterations of islet gene expression and corresponding gene variants in the context of in vivo glycemic traits from the same patients. Methods Fasting blood was collected before surgery, and pancreatic tissue was frozen after resection from 18 patients undergoing pancreatectomy. Islet tissue was isolated by laser capture microdissection. Islet transcriptome was analyzed using microarray and quantitative RT-PCR. Proteins were examined by immunohistochemistry and western blotting. The association of gene variants with insulin secretion was investigated with oral glucose tolerance test (OGTT)-derived insulin secretion measured in a large cohort of subjects at increased risk of type 2 diabetes and with hyperglycemic clamp in a subset. Results Differential gene expression between islets from normoglycemic and hyperglycemic patients was prominent for the glycolytic enzyme ALDOB and the obesity-associated gene FAIM2. The mRNA levels of both genes correlated negatively with insulin secretion and positively with HbA1c. Islets of hyperglycemic patients displayed increased ALDOB immunoreactivity in insulin-positive cells, whereas α- and δ-cells were negative. Exposure of isolated islets to hyperglycemia augmented ALDOB expression. The minor allele of the ALDOB variant rs550915 associated with significantly higher levels of C-peptide and insulin during OGTT and hyperglycemic clamp, respectively. Conclusion Our analyses suggest that increased ALDOB expression in human islets is associated with lower insulin secretion.


2020 ◽  
Vol 90 (5-6) ◽  
pp. 425-429
Author(s):  
Asieh Mansour ◽  
Mohammad Reza Mohajeri-Tehrani ◽  
Mostafa Qorbani ◽  
Mahsa Ghamari ◽  
Bagher Larijani ◽  
...  

Abstract. Objective: The objective of the present study is to investigate the effects of glutamine administration on postprandial glycemia, insulin, and C-peptide concentration in patients with type 2 diabetes. Methods: A randomized, double-blind, placebo-controlled trial was conducted on patients with type 2 diabetes so that 33 subjects were recruited in each group. The patients were randomly allocated to receive either 30 g/d glutamine or placebo (with instructions to take in half glass of ice-cold water 5 to 10 min before each main meal) for 6 weeks. Postprandial C-peptide, insulin, and glucose were measured at the baseline and at the end of the study at 30 and 90 min after consuming a meal comprising wheat-cake and reduced fat milk. Results: The repeated measures ANOVA revealed no significant difference between the groups for glucose and insulin after 6 weeks of intervention ( p > 0.05). However, C-peptide was reduced in both intervention groups at all measurement points. Between-group differences remained significant by the end of the study ( p = 0.02). Conclusions: Glutamine supplementation before each main meal does not represent an effective nutritional strategy to improve postprandial glycemic control or postprandial insulin secretion in type 2 diabetes patients.


Diabetes ◽  
2019 ◽  
Vol 68 (Supplement 1) ◽  
pp. 1516-P
Author(s):  
MASAHITO YOSHINARI ◽  
YOICHIRO HIRAKAWA ◽  
JUN HATA ◽  
MAYU HIGASHIOKA ◽  
TAKANORI HONDA ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document