scholarly journals Impaired Insulin Clearance as the Initial Regulator of Obesity-Associated Hyperinsulinemia: Novel Insight Into the Underlying Mechanism Based on Serum Bile Acid Profiles

2021 ◽  
Author(s):  
Zhenzhen Fu ◽  
Qinyi Wu ◽  
Wen Guo ◽  
Jingyu Gu ◽  
Xuqin Zheng ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Insulin Secretion ◽  
Glucose Tolerance ◽  
Glucose Tolerance Test ◽  
Tolerance Test ◽  
Insulin Clearance ◽  
Serum Bile Acid ◽  
Intravenous Glucose ◽  
Impaired Insulin ◽  
Obese Subjects

<b>OBJECTIVE</b> <div><p>To investigate the roles of insulin clearance and insulin secretion in the development of hyperinsulinemia in obese subjects and to reveal the association between insulin clearance and bile acids (BAs).</p> <p><b> </b></p> <p><b>RESEARCH DESIGN AND METHODS</b></p> <p>In cohort 1, insulin secretion, sensitivity and endogenous insulin clearance were evaluated with an oral glucose tolerance test (OGTT) in 460 recruited participants. In cohort 2, 81 participants underwent an <a>intravenous glucose tolerance test</a> (IVGTT) and a hyperinsulinemic-euglycemic clamp to assess insulin secretion, endogenous and exogenous insulin clearance, and insulin sensitivity. Based on insulin resistance levels ranging from mild to severe, nondiabetic obese participants were further divided into 10 quantiles in cohort 1 and into tertiles in cohort 2. Forty serum BAs were measured in cohort 2 to examine the association between BAs and insulin clearance.</p> <p><b> </b></p> <p><b>RESULTS</b></p> <p>All obese participants had impaired insulin clearance, and it worsened with additional insulin resistance in nondiabetic obese subjects. However, insulin secretion was unchanged from quantile 1 to 3 in cohort 1, and no difference was found in cohort 2. After adjustments for all confounding factors, serum conjugated BAs, especially glycodeoxycholic acid (GDCA, β=-0.335, P=0.004) and taurodeoxycholic acid (TDCA, β=-0.333, P=0.003), were negatively correlated with insulin clearance<a>. The ratio of </a><a></a><a>unconjugated to conjugated BAs (UnconBA/ConBA</a>, β=0.335, P=0.002) was positively correlated with insulin clearance.</p> <p><b> </b></p> <p><b>CONCLUSIONS</b></p> <p>Hyperinsulinemia in obese subjects might be primarily induced by decreased insulin clearance rather than increased insulin secretion. Changes in circulating conjugated BAs, especially GDCA and TDCA, might play an important role in regulating insulin clearance.</p></div>

scholarly journals Impaired Insulin Clearance as the Initial Regulator of Obesity-Associated Hyperinsulinemia: Novel Insight Into the Underlying Mechanism Based on Serum Bile Acid Profiles

2021 ◽  
Author(s):  
Zhenzhen Fu ◽  
Qinyi Wu ◽  
Wen Guo ◽  
Jingyu Gu ◽  
Xuqin Zheng ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Insulin Secretion ◽  
Glucose Tolerance ◽  
Glucose Tolerance Test ◽  
Tolerance Test ◽  
Insulin Clearance ◽  
Serum Bile Acid ◽  
Intravenous Glucose ◽  
Impaired Insulin ◽  
Obese Subjects

<b>OBJECTIVE</b> <div><p>To investigate the roles of insulin clearance and insulin secretion in the development of hyperinsulinemia in obese subjects and to reveal the association between insulin clearance and bile acids (BAs).</p> <p><b> </b></p> <p><b>RESEARCH DESIGN AND METHODS</b></p> <p>In cohort 1, insulin secretion, sensitivity and endogenous insulin clearance were evaluated with an oral glucose tolerance test (OGTT) in 460 recruited participants. In cohort 2, 81 participants underwent an <a>intravenous glucose tolerance test</a> (IVGTT) and a hyperinsulinemic-euglycemic clamp to assess insulin secretion, endogenous and exogenous insulin clearance, and insulin sensitivity. Based on insulin resistance levels ranging from mild to severe, nondiabetic obese participants were further divided into 10 quantiles in cohort 1 and into tertiles in cohort 2. Forty serum BAs were measured in cohort 2 to examine the association between BAs and insulin clearance.</p> <p><b> </b></p> <p><b>RESULTS</b></p> <p>All obese participants had impaired insulin clearance, and it worsened with additional insulin resistance in nondiabetic obese subjects. However, insulin secretion was unchanged from quantile 1 to 3 in cohort 1, and no difference was found in cohort 2. After adjustments for all confounding factors, serum conjugated BAs, especially glycodeoxycholic acid (GDCA, β=-0.335, P=0.004) and taurodeoxycholic acid (TDCA, β=-0.333, P=0.003), were negatively correlated with insulin clearance<a>. The ratio of </a><a></a><a>unconjugated to conjugated BAs (UnconBA/ConBA</a>, β=0.335, P=0.002) was positively correlated with insulin clearance.</p> <p><b> </b></p> <p><b>CONCLUSIONS</b></p> <p>Hyperinsulinemia in obese subjects might be primarily induced by decreased insulin clearance rather than increased insulin secretion. Changes in circulating conjugated BAs, especially GDCA and TDCA, might play an important role in regulating insulin clearance.</p></div>

scholarly journals Exenatide Is an Effective Antihyperglycaemic Agent in a Mouse Model of Wolfram Syndrome 1

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Tuuli Sedman ◽  
Kertu Rünkorg ◽  
Maarja Krass ◽  
Hendrik Luuk ◽  
Mario Plaas ◽  
...  
Keyword(s):  
Insulin Secretion ◽  
Glucose Tolerance ◽  
Mouse Model ◽  
Glucose Level ◽  
Glucose Tolerance Test ◽  
Wolfram Syndrome ◽  
Tolerance Test ◽  
Glucose Ratio ◽  
Impaired Insulin ◽  
Deficient Mice

Wolfram syndrome 1 is a very rare monogenic disease resulting in a complex of disorders including diabetes mellitus. Up to now, insulin has been used to treat these patients. Some of the monogenic forms of diabetes respond preferentially to sulphonylurea preparations. The aim of the current study was to elucidate whether exenatide, a GLP-1 receptor agonist, and glipizide, a sulphonylurea, are effective in a mouse model of Wolfram syndrome 1. Wolframin-deficient mice were used to test the effect of insulin secretagogues. Wolframin-deficient mice had nearly normal fasting glucose levels but developed hyperglycaemia after glucose challenge. Exenatide in a dose of 10 μg/kg lowered the blood glucose level in both wild-type and wolframin-deficient mice when administered during a nonfasted state and during the intraperitoneal glucose tolerance test. Glipizide (0.6 or 2 mg/kg) was not able to reduce the glucose level in wolframin-deficient animals. In contrast to other groups, wolframin-deficient mice had a lower insulin-to-glucose ratio during the intraperitoneal glucose tolerance test, indicating impaired insulin secretion. Exenatide increased the insulin-to-glucose ratio irrespective of genotype, demonstrating the ability to correct the impaired insulin secretion caused by wolframin deficiency. We conclude that GLP-1 agonists may have potential in the treatment of Wolfram syndrome-related diabetes.

scholarly journals The biochemical assessment of insulin resistance

2007 ◽  
Vol 44 (4) ◽  
pp. 324-342 ◽  
Author(s):  
Anwar Borai ◽  
Callum Livingstone ◽  
Gordon A A Ferns
Keyword(s):  
Insulin Resistance ◽  
Insulin Sensitivity ◽  
Glucose Tolerance ◽  
Glucose Tolerance Test ◽  
Tolerance Test ◽  
Model Assessment ◽  
Intravenous Glucose ◽  
Gold Standard Method ◽  
The Metabolic Syndrome ◽  
Increased Risk

Insulin resistance is a common condition, recognized to be a central feature of the metabolic syndrome, and strongly associated with an increased risk of cardiovascular disease and diabetes. The quantitative assessment of insulin sensitivity is not used for routine clinical purposes, but the emerging importance of insulin resistance has led to its wider application to research studies that have examined its pathogenesis, aetiology and consequences. The gold standard method for the determination of insulin sensitivity is the euglycaemic hyperinsulinaemic clamp from which indices of insulin sensitivity can be derived. The clamp technique is both expensive and complex to undertake and has prompted the use of surrogate methods, notably the insulin tolerance test and frequently sampled intravenous glucose tolerance test. Indices may be derived from these methods and correlate well with those derived from clamp studies. Indices can also be derived from measurements made during a standard oral glucose tolerance test and from one-off fasting specimens (e.g. homeostasis model assessment and quantitative insulin sensitivity check index). These indices lend themselves for use in large population studies where a relatively simple, inexpensive assessment is necessary. However, these tests all suffer from important limitations, including poor precision. Insulin resistance is increasingly being assessed in clinical situations, where relatively simple markers are required. Insulin-like growth factor binding protein-1 is an emerging marker which may be useful in this context.

scholarly journals Postnatal ontogeny of glucose homeostasis and insulin action in sheep

2004 ◽  
Vol 286 (6) ◽  
pp. E1050-E1059 ◽  
Author(s):  
K. L. Gatford ◽  
M. J. De Blasio ◽  
P. Thavaneswaran ◽  
J. S. Robinson ◽  
I. C. McMillen ◽  
...  
Keyword(s):  
Insulin Secretion ◽  
Insulin Sensitivity ◽  
Glucose Tolerance ◽  
Glucose Tolerance Test ◽  
Early Adulthood ◽  
Tolerance Test ◽  
Intravenous Glucose Tolerance Test ◽  
Postnatal Ontogeny ◽  
Intravenous Glucose ◽  
Female Sheep

Glucose tolerance declines with maturation and aging in several species, but the time of onset and extent of changes in insulin sensitivity and insulin secretion and their contribution to changes in glucose tolerance are unclear. We therefore determined the effect of maturation on glucose tolerance, insulin secretion, and insulin sensitivity in a longitudinal study of male and female sheep from preweaning to adulthood, and whether these measures were related across age. Glucose tolerance was assessed by intravenous glucose tolerance test (IVGTT, 0.25 g glucose/kg), insulin secretion as the integrated insulin concentration during IVGTT, and insulin sensitivity by hyperinsulinemic-euglycemic clamp (2 mU insulin·kg−1·min−1). Glucose tolerance, relative insulin secretion, and insulin sensitivity each decreased with age ( P < 0.001). The disposition index, the product of insulin sensitivity, and various measures of insulin secretion during fasting or IVGTT also decreased with age ( P < 0.001). Glucose tolerance in young adult sheep was independently predicted by insulin sensitivity ( P = 0.012) and by insulin secretion relative to integrated glucose during IVGTT ( P = 0.005). Relative insulin secretion before weaning was correlated positively with that in the adult ( P = 0.023), whereas glucose tolerance, insulin sensitivity, and disposition indexes in the adult did not correlate with those at earlier ages. We conclude that glucose tolerance declines between the first month of life and early adulthood in the sheep, reflecting decreasing insulin sensitivity and absence of compensatory insulin secretion. Nevertheless, the capacity for insulin secretion in the adult reflects that early in life, suggesting that it is determined genetically or by persistent influences of the perinatal environment.

scholarly journals Importance of quantifying insulin secretion in relation to insulin sensitivity to accurately assess beta cell function in clinical studies

2004 ◽  
pp. 97-104 ◽  
Author(s):  
B Ahren ◽  
G Pacini
Keyword(s):  
Insulin Resistance ◽  
Insulin Secretion ◽  
Insulin Sensitivity ◽  
Glucose Tolerance ◽  
Beta Cell ◽  
Beta Cell Function ◽  
Glucose Tolerance Test ◽  
Cell Function ◽  
Tolerance Test ◽  
Hyperbolic Function

Insulin sensitivity and insulin secretion are mutually related such that insulin resistance is compensated by increased insulin secretion. A correct judgement of insulin secretion therefore requires validation in relation to the insulin sensitivity in the same subject. Mathematical analyses of the relationship between insulin sensitivity and insulin secretion has revealed a hyperbolic function, such that the product of the two variables is constant. This product is usually called the disposition index. Several techniques may be used for its estimation such as data derived from the frequently sampled i.v. glucose tolerance test, the oral glucose tolerance test or the glucose-dependent arginine stimulation test or the euglycemic hyperinsulinemic clamp technique in combination with a test on insulin secretion. Using these techniques the compensatory increase in beta cell function in insulin resistance has been verified in obesity, in pregnancy and after glucocorticoid administration as has the defective beta cell function as the underlying cause of impaired glucose tolerance and type 2 diabetes. Similarly, combined analysis of insulin sensitivity and insulin secretion has shown a down-regulation of beta cell function in increased insulin sensitivity accompanying weight reduction in obesity and following exercise. Acknowledging this inverse relationship between insulin secretion and insulin sensitivity therefore requires estimation of both variables for correct assessment in any individual.

Sign in / Sign up

Export Citation Format

Share Document