Effect of 2-Bromostearate on Glucose-Phosphorylating Activities and the Dynamics of Insulin Secretion in Islets of Langerhans During Fasting

doi:10.2337/diab.33.9.858

Paper

Effect of 2-Bromostearate on Glucose-Phosphorylating Activities and the Dynamics of Insulin Secretion in Islets of Langerhans During Fasting

Published Sep 1, 1984 · F. Bedoya, R. Ramírez, E. Arilla

Diabetes

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33

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0

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Abstract

Glucose-phosphorylating activity and insulin secretion were measured in homogenates of isolated rat islets and of perfused rat pancreas, respectively. Fasting for 96 h produced a significant decrease of both low-and high-Km glucose-phosphorylating activities and blocked the insulin secretory response to glucose. In the presence of glucose, 0.25 mM 2-bromostearate, a known inhibitor of fatty acid oxidation, partially restored the insulin response to glucose that was lost during fasting. This effect paralleled the restoration of glucose-phosphorylation activities (primarily the high–Km component) seen when islets isolated from 96-h-fasted rats were preincubated with 0.25 mM 2-bromostearate. It is concluded that fasting-induced adaptations of glucose-phosphorylating enzymes could account, at least in part, for the reduced insulin secretory response to glucose. 2-Bromostearate, an inhibitor of fatty acid oxidation, is able to restore both insulin secretory response and glucose-phosphorylating activities, suggesting possible interrelations among the correlated impairment in insulin secretion, islet glucose-phosphorylating activity, islet glucose metabolism, and the oxidation of fatty acids in the B-cell during fasting.

In Vitro Study

Study Snapshot

2-Bromostearate partially restores insulin secretory response and glucose-phosphorylating activities in islets during fasting, suggesting potential interrelations between insulin secretion, glucose metabolism, and fatty acid oxidation in the B-cell.

PopulationOlder adults (50-71 years)

Sample size24

MethodsObservational

OutcomesBody Mass Index projections

ResultsSocial networks mitigate obesity in older groups.

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Paper

Effect of 2-Bromostearate on Glucose-Phosphorylating Activities and the Dynamics of Insulin Secretion in Islets of Langerhans During Fasting

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Citations

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