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

The aim of this work was to study the effects of a computer-driven mental arithmetic task on blood glucose in a group of four male and four female euglycemic Caucasians and a group of seven male and six female euglycemic Pima Indians. Approximately 60% of euglycemic Pima Indian Native Americans eventually develop type 2 diabetes, while only 5% of Caucasians develop the disease. All subjects had normal glucose tolerance. Subjects were given a standard breakfast; 2 h later, they were given a computerized mental arithmetic stress test for 10 min. Before, during and after the test, several variables were analyzed, including serum concentrations of glucose, insulin, glucagon and plasma cortisol and catecholamines. Heart rate, systolic and diastolic blood pressure and all the stress hormones increased during stress and decreased during recovery in all subjects. Blood glucose consistently declined one hour after the meal in all subjects. However, while it continued to decline following stress in seven out of eight Caucasian subjects, it consistently increased during and following stress in 10 out of 13 Pima Indians. Fasting serum glucose in Pima Indians and Caucasians was respectively 5.07 + 0.08 mM and 5.04 + 0.09 mM. Two-hour post-prandial values were 5.63 + 0.22 mM and 5.48 + 0.19 mM respectively, whereas post-stress values were 6.15 + 0.19 mM for Pima Indians and 5.22 + 0.20 mM for Caucasians. Both serum glucose means following stress (t = 3.1, P < 0.005) and the direction of change in serum glucose in response to mental arithmetic (chi 2 = 8.2, P < 0.01) clearly differentiated Pimas from Caucasians.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Glycemic response to stress is altered in euglycemic Pima Indians. 786 78

Non-insulin-dependent diabetes mellitus is a complex metabolic disorder that involves numerous biochemical abnormalities, a heterogenous clinical picture, and a polygenic hereditary component. The pathophysiologic state involves increased basal hepatic glucose production, decreased insulin-mediated glucose utilization in target tissues, and altered pancreatic function with decreased beta cell function and enhanced glucagon secretion. Prospective studies indicate that insulin resistance and hyperinsulinemia exist in the prediabetic state at a time when glucose tolerance is normal. When hyperglycemia supervenes, both insulin secretion and insulin-mediated glucose utilization are further compromised, mediated in part by sustained hyperglycemia itself. Insulin resistance may occur at any level in the biologic action of insulin, from initial binding to cell surface receptors to the phosphorylation cascade that is initiated by autophosphorylation of the insulin receptor. Receptors isolated from patients with non-insulin-dependent diabetes mellitus have compromised autophosphorylation-kinase activity when isolated from adipocytes, liver, erythrocytes, and skeletal muscle. The magnitude of the decrease in insulin receptor kinase activity is correlated with the degree of fasting hyperglycemia. However, the defect in insulin receptor kinase activity is normalized after weight reduction or other measures that reduce hyperglycemia, indicating the secondary nature of the defect. Clarification of the mechanisms underlying insulin resistance in non-insulin-dependent diabetes mellitus will lead to new treatment modalities for this disease.
 ...
PMID:Insulin resistance and non-insulin-dependent diabetes mellitus: cellular and molecular mechanisms. 790 Jun 97

Glucagon-like peptide-1 (GLP-1) is a hormone derived from the preproglucagon molecule that is secreted by intestinal L cells and stimulates insulin secretion from beta cells. The GLP-1 receptor is a candidate gene for diabetes mellitus, as mutations may induce the impaired insulin response that is a characteristic feature of NIDDM. To study the relationship between the GLP-1 receptor gene and NIDDM, linkage of a microsatellite polymorphism flanking the GLP-1 receptor gene with diabetes was investigated in three Caucasian families with MODY and in the nuclear families of 12 NIDDM probands. A cumulative LOD score -8.50 excludes linkage in these MODY pedigrees. A LOD score of -1.24 in the NIDDM nuclear pedigrees makes linkage improbable. Mutations in or near the GLP-1 receptor gene are unlikely to be the major cause of the inherited predisposition to NIDDM in Caucasian pedigrees, but we cannot exclude a role for this locus in a polygenic model or a major role in some pedigrees.
 ...
PMID:Non-linkage of the glucagon-like peptide 1 receptor gene with maturity onset diabetes of the young. 795 45

Glucagon-like peptide-1 (GLP-1) stimulate glucose dependent insulin secretion from beta-cells. Human cDNA and the gene of the receptor for the GLP-1 was isolated. Two polymorphic simple tandem repeats were found in the gene. Using these markers, role of GLP-1 receptor mutations in the pathogenesis of NIDDM was studied. No association was found between the marker alleles and NIDDM in African American or in Japanese. Linkage was rejected between the GLP-1 receptor gene and NIDDM in Caucasian late-onset NIDDM families and in French MODY families. Mutations in the GLP-1 receptor gene do not appear to be major genetic determinants of NIDDM. Further studies are required to exclude the minor role of the gene in a fraction of NIDDM patients.
 ...
PMID:[Human glucagon-like peptide-1 receptor gene in NIDDM]. 798 6

To elucidate the pathogenesis of diabetes in spontaneously diabetic Chinese hamsters (CHAD strain), a longitudinal study from just after weaning to overt diabetic state was performed. Fasting and non-fasting plasma glucose, non-fasting plasma insulin and pancreatic hormone contents (insulin, glucagon and amylin) were measured, and light microscopic examination of pancreatic islets by immunohistochemical technique and pancreas perfusion study were performed. No insulitis was found in the islets of the CHAD strain. In animals aged 1 month, there was no significant difference in the percentage of B-cell area to islet area between the CHAD strain and the control. At this stage, hyperinsulinemia was observed despite normal plasma glucose levels both in fasting and non-fasting states. In the animals of the CHAD strain aged 2-4 months, insulin secretion from the pancreas, pancreatic insulin content and non-fasting plasma insulin level decreased in proportion to the decrease of B-cell mass. In animals aged about ten months, severe hyperglycemia and hypoinsulinemia were observed. We demonstrated the existence of amylin-like immunoreactivity in the B-cells of Chinese hamsters. However, no amyloid deposit was observed in the islets of the CHAD strain. After the onset of diabetes, amylin secretion from the pancreas and pancreatic amylin content in the CHAD strain were significantly lower than those in the control. We demonstrated the natural history of B-cell dysfunction in the CHAD strain. It could mean the process of B-cell exhaustion. The profile of the CHAD strain is similar to some types of human NIDDM. Therefore, the CHAD strain is a useful diabetic model in the study of NIDDM.
 ...
PMID:Natural history of B-cell dysfunction in spontaneously diabetic Chinese hamsters. 798 44

To evaluate beta-cell function in patients with pancreatic cancer, the glucagon stimulation test was performed in seven patients with pancreatic adenocarcinoma, seven patients with type I diabetes mellitus, seven patients with type II diabetes mellitus, and in seven healthy controls. C-peptide serum levels were determined before and after a 1-mg i.v. glucagon injection. Basal C-peptide values were normal or slightly increased in pancreatic cancer and type II diabetic patients and low in type I diabetic patients. Following glucagon stimulation, no significant increase was observed in C-peptide values of type I diabetics and pancreatic cancer patients, whereas significant increases occurred in controls and type II diabetics. It is concluded that the altered beta-cell function found in pancreatic cancer patients may lead to hyperglycemia, which is frequently associated with this tumor type.
 ...
PMID:Beta-cell function in pancreatic adenocarcinoma. 802 55

Despite similar glycemic profiles, higher insulin levels are achieved following oral versus intravenous administration of glucose. This discrepancy is due to the incretin effect and is believed to be mediated via stimulation of beta-cells by hormone(s) released from the gut. The leading gut hormone candidates are glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide (GLP-1). To determine the relative insulinotropic activity of these peptides, we infused GLP-1(7-37) and GIP into normal subjects and patients with non-insulin dependent diabetes mellitus (NIDDM). In normal subjects during euglycemia, GLP-1(7-37) stimulated insulin release, whereas GIP did not. Using the Andres clamp technique, we established stable hyperglycemia for 2 h (5.4 mmol/l above the basal level). During the second hour, either GIP, GLP-1(7-37), or both were infused in normal healthy volunteers and in patients with NIDDM. In normal subjects, at a glucose level of 10.4 mmol/l, the 90-120 min insulin response was 279 pmol/l. GIP at a dose of 1, 2 or 4 pmol/kg/min augmented the 90-120 min insulin response by 69, 841 and 920 pmol/l, while GLP-1(7-37), at a dose of 1.5 pmol/kg/min augmented the insulin response by 2106 pmol/l. When both hormones were administered simultaneously, the augmentation was additive--2813 pmol/l. In the diabetic subjects, GIP had no effect, while GLP-1(7-37) augmented the insulin response by 929 pmol/l. We conclude that in normal healthy subjects, GLP-1(7-37), on a molar basis, is several times more potent than GIP at equivalent glycemic conditions. The additive insulinotropic effect suggests that more than one incretin may be responsible for the greater insulin levels observed following oral administration of glucose compared to the intravenous route. In NIDDM, GIP had no insulinotropic effect, while GLP-1(7-37) had a marked effect. This suggests that GLP-1(7-37) may have therapeutic potential as a hypoglycemic agent in NIDDM patients.
 ...
PMID:The insulinotropic actions of glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (7-37) in normal and diabetic subjects. 803 84

Elevated fasting proinsulin immunoreactive material (PIM) has previously been found in patients with type 2 (non-insulin-dependent) diabetes mellitus. It is not known whether this is a genetic trait or whether it is related to the manifestation of type 2 diabetes. Neither is it clear whether the raised fasting insulin immunoreactivity previously observed in first-degree relatives of patients with type 2 diabetes is due to raised PIM. Furthermore, it has not been investigated whether first-degree relatives have altered PIM responses to different secretagogues. To study this, PIM, insulin and C-peptide were measured in patients with type 2 diabetes, in their first-degree relatives and in healthy control subjects in the fasting state and in relatives and controls during a hyperglycemic clamp. At the end of the hyperglycemic clamp, 0.5 mg of glucagon was given intravenously to stress the beta cells further. Fasting PIM concentrations were significantly higher in patients with type 2 diabetes (P < 0.05). These patients did not have significantly elevated fasting insulin levels when corrected for PIM. In the relatives, fasting insulin concentrations were elevated but PIM levels were normal suggesting that the increase in fasting insulin concentrations reflected an increase in true insulin. The incremental PIM, insulin and C-peptide responses to glucose and glucagon in the relatives were not different from those in the controls. We conclude that elevated fasting PIM levels in patients with type 2 diabetes seem not to be a genetic trait.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Proportional proinsulin responses in first-degree relatives of patients with type 2 diabetes mellitus. 811 Oct 72

Basic research on the cellular mechanisms that control the expression of the gene encoding glucagon has led to the discovery of proglucagon, which is processed alternatively by tissue-specific proteolysis to produce glucagon in the pancreatic alpha cells and a GLP-1 in the intestines. GLP-1 hormone is released into the circulation from intestinal L cells in response to meals and is the most potent incretin hormone known; GLP-1 and GIP appear to account for most, if not all, of the intestinal incretin effect in the augmentation of glucose-stimulated insulin secretion. Analyses of the mechanisms of action of GLP-1 and of glucose on isolated cultured rat beta cells using patch-clamp techniques to record ion channel activities has led to the glucose competence concept in which the combined glucose-signaling and GLP-1/cAMP-signaling pathways are required to affect depolarization of beta cells and to thereby stimulate insulin secretion. It is hypothesized that, among other possible target channels, the K-ATP channel is key first event in GLP-1/glucose-mediated activation of the beta cell secretory response. It is proposed that at least one factor contributing to the pathogenesis of NIDDM is a desensitization of the GLP-1 receptor on beta cells induced by the hypersecretion of GLP-1. Because of the discoveries that GLP-1 stimulates both secretion and production of insulin, and that the actions of GLP-1 are entirely glucose-dependent, GLP-1 may provide unique advantages over the sulfonylurea drugs in the treatment of NIDDM.
 ...
PMID:The incretin notion and its relevance to diabetes. 812 72

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.
 ...
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


<< Previous 1 2 3 4 5 6 7 8 9 10