Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01275 (glucagon)
 26,492 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The present study deals with the insulinotropic action of the dimethyl ester of succinic acid (SAD), considered as a potential tool for the treatment of non-insulin-dependent diabetes mellitus. In the perfused pancreas prepared from either euglycemic rats or animals first infused for 48 hours with a solution of D-glucose, SAD (10 mM) markedly enhanced insulin output evoked by a high concentration of D-glucose (16.7 mM), whether in the absence or presence of glimepiride (0.5 microM). The succinate ester failed, however, to affect glucagon secretion. Thus, SAD indeed displays favourable attributes for stimulation of insulin release in type 2 diabetes, with emphasis on its insulinotropic efficiency at high concentrations of D-glucose in an animal model of B-cell glucotoxicity.
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PMID:Enhancement by succinic acid dimethyl ester of insulin release evoked by D-glucose and glimepiride in the perfused pancreas of normoglycemic and hyperglycemic rats. 818 62

The glucagon-like peptide 1 (7-36) amide (GLP-1, 1.0 nM) was administered to isolated rat pancreases perfused either in the absence of exogenous nutrient or presence of 10 mM succinic acid dimethyl ester (SAD). In the absence of any exogenous nutrient, GLP-1 failed to affect either insulin or glucagon release. The administration of SAD caused a biphasic stimulation of insulin output and inhibited glucagon secretion. In the presence of SAD, GLP-1 still failed to affect glucagon release, but markedly enhanced insulin secretion. These findings indicate that GLP-1 is not truly a glucose-dependent, but rather nutrient-dependent insulin secretagogue. They also suggest that non-glucidic nutrients, such as SAD, could be used to optimalize the B-cell secretory response to GLP-1 in non-insulin-dependent diabetes mellitus.
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PMID:Potentiation of glucagon-like peptide 1 insulinotropic action by succinic acid dimethyl ester. 861 71

Glucagon-like peptide 1 (GLP-1) is often referred to as a glucose-dependent insulinotropic agent and is currently under investigation as a tool in the treatment of noninsulin-dependent diabetes. This report shows that, in the absence of glucose, a nonglucidic nutrient, namely succinic acid dimethyl ester (SAD), allows full expression of the insulinotropic potential of GLP-1 in the perfused pancreas from diabetic GK rats. Thus, whereas the insulin and glucagon responses to GLP-1 in GK rats differ from those previously documented in nondiabetic animals when tested in the absence of exogenous nutrient, the secretory response of the endocrine pancreas to GLP-1 is virtually normalized in the GK rats when SAD is incorporated into the perfusate. It is proposed, therefore, that nonglucidic nutrients, such as SAD, may optimalize the B-cell secretory response to GLP-1 in noninsulin-dependent diabetes mellitus.
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PMID:Potentiation of GLP-1 insulinotropic action by a nonglucidic nutrient in the pancreas of diabetic GK rats. 890

D-mannoheptulose was recently proposed to be transported into cells by GLUT2, whereas its hexaacetate ester may cross the plasma membrane without requiring the intervention of a specific carrier system. In the light of these proposals, the effects of unesterified D-mannoheptulose and D-mannoheptulose hexaacetate upon hormonal secretion by the perfused rat pancreas were now investigated. Unesterified D-mannoheptulose (1.7 mM) inhibited insulin release and, in most cases, somatostatin output, whereas it augmented glucagon secretion by pancreases exposed to D-glucose (3.3 mM) in the presence of the dimethyl ester of succinic acid (SAD, 10.0 mM). The heptose failed, however, to affect hormonal secretion in the sole presence of SAD. D-mannoheptulose hexaacetate (also 1.7 mM) reproduced, within limits, the effects of unesterified D-mannoheptulose in pancreases exposed to both D-glucose and SAD. In addition, however, the ester displayed a positive effect upon the secretion of the three hormones, even in the sole presence of SAD. These findings support the view that monosaccharide esters may affect the secretion of pancreatic hormones in a dual manner, linked to both the metabolic response to their glucidic moiety and a direct effect of the ester itself. Moreover, they reveal that unesterified D-mannoheptulose is able to antagonize the effect of D-glucose upon hormonal secretion even in cells claimed not to contain GLUT2. The modality by which D-mannoheptulose apparently gains access to the cytosol of these cells remains to be elucidated.
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PMID:Effects of D-mannoheptulose and its hexaacetate ester on hormonal secretion from the perfused pancreas. 1089 57

It was recently proposed that suitable succinic acid esters could be used to potentiate the insulinotropic action of glucagon-like peptide 1 (GLP-1) in the treatment of type-2 diabetes mellitus. In such a perspective, the present study aimed mainly at investigating whether exendin-4 (Ex-4), a peptide structurally related to GLP-1(7-36)amide, and succinic acid dimethyl ester (SAD) also act synergistically upon insulin secretion in anaesthetized rats. Despite a higher plasma insulin concentration in SAD-infused rats (5.5+/-1.1 ng/ml) than in saline-infused animals (1.9+/-0.7 ng/ml), the intravenous injection of Ex-4 augmented to a greater extent the plasma concentration of insulin in the former rats (+7.4+/-2.5 ng/ml) than in the latter animals (+2.8+/-0.6 ng/ml). These findings document that the insulinotropic actions of Ex-4 and GLP-1 display comparable nutrient dependency, being both potentiated by a non-glucidic nutrient secretagogue such as SAD.
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PMID:Synergistic insulinotropic effects of succinic acid dimethyl ester and exendin-4 in anaesthetized rats. 1149 54

Glucagon-like peptide-1 (GLP-1) acts as a nutrient-dependent insulin-releasing agent, and its insulinotropic action is enhanced by nutrient secretagogues, such as the dimethyl ester of succinic acid (SAD). In the present study, a primed constant infusion of SAD (0.5 micromol followed by 0.25 micromol/min both per g of body wt) was found to increase plasma insulin concentration in fed anesthetized rats, to potentiate the B-cell secretory response to GLP-1 (0.5 pmol/g of body wt), and to unmask the hypoglycemic potential of the gastrointestinal hormone. In the SAD-infused rats, the infusion of exendin(9-39)amide (5.0 pmol/min per g of body wt), 1 min before and 3 min after GLP-1 injection, decreased plasma insulin concentration before GLP-1 injection, suppressed the B-cell secretory response to GLP-1, and both delayed and minimized its hypoglycemic action. It is proposed, therefore, that exendin (9-39)amide could represent a tool in the treatment of alimentary or reactive hypoglycemia.
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PMID:Suppression by exendin(9-39)amide of glucagon-like peptide-1 insulinotropic action in rats infused with dimethyl ester of succinic acid. 1176

We investigated the in vitro effects of therapeutical concentrations of S 21403 (a succinic acid derivative also known as KAD 1229 and mitiglinide) on insulin and glucagon secretion during a metabolic stimulus (glucose rising from 5 to 8.33 mM) or at a stable 2.22 mM glucose using the isolated perfused rat pancreas model, and we compared them with the patterns of repaglinide and glibenclamide. Control perfusions were also performed. During 8.33 mM glucose, insulin release peaked to 339.12+/-22.87 microU/ml in controls. S 21403 enhanced insulin release (first peak 413.02+/-14.90 microU/ml; P<0.03 vs. controls, P=ns vs. repaglinide, P<0.005 vs. glibenclamide). Repaglinide increased glucose-induced first peak secretion to 409.33+/-20.05 microU/ml within the eighth minute (P<0.05 vs. controls, P<0.01 vs. glibenclamide). Glibenclamide did not affect the first phase of glucose-induced insulin release (peak of 338.41+/-29.79 microU/ml) but potentiated and delayed the second phase. No drug affected glucagon release. In conclusion, S 21403 induces a faster, more physiological pattern of insulin release than the other drugs we tested.
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PMID:Effects of S 21403 on hormone secretion from isolated rat pancreas at different glucose concentrations. 1245 May 80

Glucagon-like peptide-1 (GLP-1), an incretin hormone which helps to regulate plasma glucose levels, is considered a potential agent for the treatment of type-2 diabetes mellitus, because of its insulinotropic capacity and insulinomimetic actions. In normal conditions, the beta-cell secretory response to GLP-1 is modulated by the extracellular concentration of D-glucose; however, the recognition of D-glucose by the beta-cell is often impaired in type-2 diabetes, and this could impede the full GLP-1 insulinotropic action. Non-glucidic substrates, such as the dimethyl ester of succinic acid, restore the effect of GLP-1 in the isolated perfused rat pancreas of normal or diabetic rats, in the absence of any other exogenous nutrient; likewise, the dimethyl ester of succinic or L-glutamic acid, and the monomethyl ester of pyruvic acid, potentiate the in vivo beta-cell secretory response to GLP-1 in normal and diabetic rats. Therefore, it was proposed that nutrients susceptible to bypass the site-specific defects of the diabetic beta-cell, could be used to potentiate and/or prolong the insulinotropic action of antidiabetic agents such as GLP-1. In vitro, GLP-1 insulin-like effects on glucose metabolism have been documented in normal and diabetic rat liver, and in rat and human skeletal muscle. In rat and human adipocytes, GLP-1 is lipolytic and/or lipogenic, and also stimulates parameters involved in the glucose metabolism. In liver, muscle and fat, GLP-1 seems to act through specific receptors, apparently different--at least in liver and muscle--in structure or signaling pathway from the pancreatic one. It is proposed that an inositolphosphoglycan might be a second messenger of GLP-1 action in extrapancreatic tissues.
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PMID:Pancreatic and extrapancreatic effects of GLP-1. 1268 38