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)

In an attempt to define the pancreatic B cell function in the elderly, we subjected 88 non-obese individuals (aged between 21 and 88) to an oral glucose tolerance test (OGTT), a simple glucagon test (SGT) and OGTT-glucagon test, in which the plasma glucose, insulin and serum C-peptide (CPR) were measured. We investigated heterogeneity in glucose intolerance in the elderly and its relationship to atherosclerosis. In the OGTT and SGT test, the insulin responses (SIRI/SPG ratios) for normal, borderline and DM1 (fasting plasma glucose less than 140 mg/dl and 2 h-PG greater than or equal to 200 mg/dl) groups of the elderly (60 and above) were not significantly different from those for normal group of young and middle-aged (below 60) and were significantly higher for elderly group than for the young and middle-aged group in each glucose tolerance group. But the insulin responses for the DM2 (fasting plasma glucose greater than or equal to 140 mg/dl and 2 h-PG greater than or equal to 200 mg/dl) group of the elderly were not significantly different from those for the DM1 and DM2 groups of young and middle-aged. The insulin responses of normal, borderline and DM1 groups of the elderly with atherosclerosis were significantly higher than those of the comparable groups without atherosclerosis, while the insulin responses of the borderline and DM1 groups of the elderly with atherosclerosis were similar to those of the control group of the young. In the OGTT-glucagon test, there were no differences in the insulin response or serum CPR response among the normal, borderline and DM1 groups of the elderly, and these responses were significantly higher for the elderly group than the for young and middle-aged group in each glucose tolerance group. But these responses for the DM2 group of the elderly were not significantly different from those for the DM1 and DM2 groups of the young and middle-aged. These results indicate that the pancreatic B cell function of the normal group in the elderly remains favorable while mildly impaired glucose tolerance was exhibited by the borderline and DM1 groups, who are comparable with the normal group of the young and middle-aged. But this function was clearly reduced in the DM2 group of the elderly. These findings suggest that there is a subgroup in the elderly, which has clinically evident atherosclerosis, mild glucose intolerance and high insulin response. Their pancreatic B cell function remains favorable.
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PMID:[Pancreatic B cell function and glucose intolerance in the elderly]. 265 22

We examined the ability of an equivalent increase in circulating glucose concentrations to inhibit endogenous glucose production (EGP) and to stimulate glucose metabolism in patients with Type 2 diabetes mellitus (DM2). Somatostatin was infused in the presence of basal replacements of glucoregulatory hormones and plasma glucose was maintained either at 90 or 180 mg/dl. Overnight low-dose insulin was used to normalize the plasma glucose levels in DM2 before initiation of the study protocol. In the presence of identical and constant plasma insulin, glucagon, and growth hormone concentrations, a doubling of the plasma glucose levels inhibited EGP by 42% and stimulated peripheral glucose uptake by 69% in nondiabetic subjects. However, the same increment in the plasma glucose concentrations failed to lower EGP, and stimulated glucose uptake by only 49% in patients with DM2. The rate of glucose infusion required to maintain the same hyperglycemic plateau was 58% lower in DM2 than in nondiabetic individuals. Despite diminished rates of total glucose uptake during hyperglycemia, the ability of glucose per se (at basal insulin) to stimulate whole body glycogen synthesis (glucose uptake minus glycolysis) was comparable in DM2 and in nondiabetic subjects. To examine the mechanisms responsible for the lack of inhibition of EGP by hyperglycemia in DM2 we also assessed the rates of total glucose output (TGO), i.e., flux through glucose-6-phosphatase, and the rate of glucose cycling in a subgroup of the study subjects. In the nondiabetic group, hyperglycemia inhibited TGO by 35%, while glucose cycling did not change significantly. In DM2, neither TGO or glucose cycling was affected by hyperglycemia. The lack of increase in glucose cycling in the face of a doubling in circulating glucose concentrations suggested that hyperglycemia at basal insulin inhibits glucose-6-phosphatase activity in vivo. Conversely, the lack of increase in glucose cycling in the presence of hyperglycemia and unchanged TGO suggest that the increase in the plasma glucose concentration failed to enhance the flux through glucokinase in DM2. In summary, both lack of inhibition of EGP and diminished stimulation of glucose uptake contribute to impaired glucose effectiveness in DM2. The abilities of glucose at basal insulin to both increase the flux through glucokinase and to inhibit the flux through glucose-6-phosphatase are impaired in DM2. Conversely, glycogen synthesis is exquisitely sensitive to changes in plasma glucose in patients with DM2.
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PMID:Regulation of endogenous glucose production by glucose per se is impaired in type 2 diabetes mellitus. 971 Apr 43

With the aim of investigating glucose-mediated glucose disposal (glucose effectiveness [GE]) in 15 (3 female and 12 male subjects) insulin-resistant normoglycemic relatives of patients with type 2 diabetes (DM2), and 15 age-, sex-, and BMI-matched control subjects without a family history of DM2, we performed 2 studies: 1) a 5-h euglycemic near-normoinsulinemic pancreatic clamp with somatostatin (360 microg/h), insulin (0.25 mU x kg(-1) x min(-1)), glucagon (0.5 ng x kg(-1) x min(-1)), growth hormone (6 ng x kg(-1) x min(-1)), and tritiated glucose infusion and indirect calorimetry; and 2) on a separate day, an identical 5-h clamp but at hyperglycemia (approximately 12 mmol/l) over the last 2 h. Fasting plasma insulin (PI) concentrations were elevated in the relatives compared with control subjects (49 +/- 6 vs. 32 +/- 5 pmol/l, P < 0.04), whereas plasma glucose (PG) was not (5.6 +/- 0.1 vs. 5.5 +/-0.1 mmol/l). At the end (i.e., 4.5-5.0 h) of the euglycemic clamp (PG, 6.1 +/- 0.4 vs. 5.6 +/- 0.1 mmol/l; PI, 78 +/- 5 vs. 73 +/-6 pmol/l), peripheral glucose uptake (Rd(euglycemia)) was decreased in the relatives (2.93 +/- 0.08 vs. 3.70 +/-0.23 mg x min(-1) x kg(-1) fat free mass [FFM], P < 0.005), due to a decreased nonoxidative glucose disposal (0.83 +/-0.21 vs. 1.62 +/- 0.19 mg x min(-1) x kg(-1) FFM, P < 0.01), but hepatic glucose production (HGP) was increased (1.97 +/-0.19 vs. 1.50 +/- 0.13 mg x min(-1) x kg(-1) FFM, P < 0.05). At the matched end of the hyperglycemic clamp (PG, 12.7 +/-0.2 vs. 12.6 +/- 0.2 mmol/l; PI, 87 +/- 5 vs. 78 +/- 7 pmol/l), peripheral glucose disposal (Rd(hyperglycemia)) (5.52 +/- 0.22 vs. 5.92 +/- 0.29 mg x min(-1) x kg(-1) FFM, NS), nonoxidative glucose disposal (2.93 +/- 0.18 vs. 2.78 +/- 0.25 mg x min(-1) x kg(-1) FFM, NS), and HGP(hyperglycemia) (1.20 +/- 0.09 vs. 1.37 +/-0.23 mg x min(-1) x kg(-1) FFM, NS) were all identical. When the effectiveness of glucose itself on glucose uptake and production [(Rd(hyperglycemia) - Rd(euglycemia))/deltaPG and (HGP(euglycemia)- HGP(hyperglycemia))/deltaPG] was calculated, the relatives had a 22% increase in peripheral uptake (0.022 +/- 0.002 vs. 0.018 +/- 0.002 mg x min(-1) x kg(-1) FFM per mg/dl), due to a significantly increased nonoxidative glucose metabolism and enhanced suppression of HGP (0.0076 +/- 0.0021 vs. 0.0011 +/- 0.0022 mg x min(-1) x kg(-1) FFM per mg/dl, P < 0.05). In conclusion, in insulin-resistant relatives of DM2 patients, whole-body glucose-mediated glucose disposal is increased by GE enhancement of the muscle nonoxidative glucose pathway and by GE enhancement of the suppression of HGP. These mechanisms may represent a compensatory mechanism to the ongoing insulin resistance of these relatives.
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PMID:Glucose-mediated glucose disposal in insulin-resistant normoglycemic relatives of type 2 diabetic patients. 1090 80

We have previously demonstrated abnormalities in insulin secretion in adolescents with type 2 diabetes mellitus (DM2) in response to the mixed meal test and to glucagon. In order to further assess beta-cell function in DM2, we measured insulin and C-peptide responses to oral glucose in adolescents with DM2 in comparison to non-diabetic obese and lean adolescents. We studied 20 patients with DM2, 25 obese adolescents with matching body mass index (BMI) (33.8 +/- 1.4 vs 34.3 +/- 1.0 kg/m2), and 12 non-obese control adolescents (BMI 22.6 +/- 0.6 kg/m2). Mean age, sex and sexual maturation did not differ between the three groups. All adolescents with DM2 had negative islet cell antibodies (ICA); five patients were on diet and 15 on insulin treatment. Fasting lipid profiles were determined in all participants. Plasma glucose and serum C-peptide and insulin levels were measured at 0, 30, 60, 90, and 120 min after an oral glucose load. The C-peptide increment (deltaCP) was calculated as peak minus fasting C-peptide. Area under the curve (AUC) was estimated using the trapezoid method. Insulin resistance was estimated using the HOMA model (HOMA-IR). The first phase of insulin secretion (PH1) was computed using a previously published formula. Serum triglyceride levels were significantly higher in the patients with DM2 compared to the non-obese controls (1.4 +/- 0.1 vs 0.9 +/- 0.1 mmol/l; p = 0.02). Plasma glucose AUC was greater in the patients with DM2 compared to the obese and non-obese control groups (1,660 +/- 130 vs 717 +/- 17 vs 647 +/- 14 mmol/l x min; p < 0.0001). ACP was lower in adolescents with DM2 than in obese and non-obese adolescents (761 +/- 132 vs 1,721 +/- 165 vs 1,225 +/- 165 pmol/l; p < 0.001). Insulin AUC was lower in the patients with DM2 compared to obese controls (888 +/- 206 vs 1,606 +/- 166 pmol/l x h; p = 0.009), but comparable to that of the non-obese controls (888 +/- 206 vs 852 +/- 222 pmol/l x h; p = 0.9). Insulin AUC was also higher in the obese than in the non-obese group (p = 0.05). PH1 was significantly higher in the obese group compared to the patients with DM2 as well as to the non-obese controls (2,614 +/- 2,47.9 vs 929.6 +/- 403.5 vs 1,946 +/- 300.6 pmol/l, respectively; p = 0.001). PH1 was also higher in the non-obese controls than in the patients with DM2 (p = 0.05). HOMA-IR was three-fold higher in the patients with DM2 than in the BMI-matched obese group, and five-fold higher than in the lean controls (14.3 +/- 1.2 vs 5.4 +/- 0.8 vs 2.9 +/- 0.4; p = 0.0002). Adolescents with DM2 have dyslipidemia, a significant cardiovascular risk factor. Decreased beta-cell function is characteristic of adolescents with DM2 in the presence of severe insulin resistance.
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PMID:Type 2 diabetes mellitus in African-American adolescents: impaired beta-cell function in the face of severe insulin resistance. 1656 86

The fact that fat issue is an endocrine gland secreting several hormones participating in the pathogenesis of type 2 diabetes mellitus (DM2) is universally recognized. Fat issue secretes leptin, tumor necrosis factor alpha, resistin, adiponectin, interleukin-6, free fatty acids, visfatin, omentin, perilipin, and other substances that influence the condition of insulinoresistance, one of the main factors responsible for DM2. Subcutaneous fat and visceral depot fat tissue differ in the spectrum of hormones they produce; the list of these hormones is presented in the article. The presence of abdominal or visceral obesity is combined with significant insulinoresistance, which, in its turn, increases the risk of vascular complications of diabetes. The article also cover the participation of other mechanisms - insulin secretion defect, oxidation stress, low secretion of glucagon-like peptide 1, apoptosis, an increased quantity of amyloid and the fl-cell pull in the pancreatic island--in DM2 pathogenesis. The authors present data on the secretion of leptin, resistin, adiponectin, and tumor necrosis factor a, as well as the condition of the functional activity of beta-cells and the degree of insulinoresistance in 30 DM2 patients receiving dietotherapy.
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PMID:[The role of the fat tissue and its hormones in the mechanisms of insulin resistance and the development of type 2 diabetes mellitus]. 1788 4

Glucagon-like peptide 1 (GLP-1) is secreted from enteroendocrine L-cells in response to oral nutrient intake and elicits glucose-stimulated insulin secretion while suppressing glucagon secretion. Moreover slows gastric emptying -reducing postprandial glycemic excursions-, reduces body weight, systolic blood pressure and has beneficial effects in the cardiovascular and central nervous systems. Since the 1990s, the efficacy of GLP-1 in reducing blood glucose levels in type 2 diabetes (DM2) was well known. However, GLP-1 should be administered by chronic subcutaneous infusion because of the rapid cleavage by the enzyme dipeptidyl peptidase 4 (DPP-4). Hence, DPP-4 inhibitors -which increase pseudo-physiologically endogenous GLP-1 levels- were developed. In addition, several GLP-1 receptor agonists have been designed to avoid DPP-4-breakdown and/or rapid renal elimination and, therefore, induce a pharmacologic effect in the GLP-1 receptor: short-acting, long-acting, and prolonged-acting GLP-1 analogs. Each class has different structural, pharmacodynamic and clinical properties and could be administered in different therapeutical regimens giving us the opportunity to individualize the therapy of DM2.
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PMID:[Characteristics and types of GLP-1 receptor agonists. An opportunity for individualized therapy]. 2532 38

Glucagon-like peptide-1 (GLP-1) receptor agonists are a new group of drugs for the treatment of type 2 diabetes mellitus (DM2). In the present article, we review the available evidence on the efficacy of GLP-1 receptor agonists as glucose-lowering agents, their place in therapeutic algorithms, and the clinical factors associated with a favorable treatment response. Finally, we describe the clinical characteristics of patients who may benefit from these drugs.
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PMID:[Effects of GLP-1 receptor agonists on carbohydrate metabolism control]. 2532 39

Glucagon-like peptide 1 (GLP-1) is secreted from enteroendocrine L-cells in response to oral nutrient intake and elicits glucose-stimulated insulin secretion while suppressing glucagon secretion. Moreover slows gastric emptying -reducing postprandial glycemic excursions-, reduces body weight, systolic blood pressure and has beneficial effects in the cardiovascular and central nervous systems. Since the 1990s, the efficacy of GLP-1 in reducing blood glucose levels in type 2 diabetes (DM2) was well known. However, GLP-1 should be administered by chronic subcutaneous infusion because of the rapid cleavage by the enzyme dipeptidyl peptidase 4 (DPP-4). Hence, DPP-4 inhibitors -which increase pseudo-physiologically endogenous GLP-1 levels- were developed. In addition, several GLP-1 receptor agonists have been designed to avoid DPP-4-breakdown and/or rapid renal elimination and, therefore, induce a pharmacologic effect in the GLP-1 receptor: short-acting, long-acting, and prolonged-acting GLP-1 analogs. Each class has different structural, pharmacodynamic and clinical properties and could be administered in different therapeutical regimens giving us the opportunity to individualize the therapy of DM2.
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PMID:[Characteristics and types of GLP-1 receptor agonists. An opportunity for individualized therapy]. 2543 60

Glucagon-like peptide-1 (GLP-1) receptor agonists are a new group of drugs for the treatment of type 2 diabetes mellitus (DM2). In the present article, we review the available evidence on the efficacy of GLP-1 receptor agonists as glucose-lowering agents, their place in therapeutic algorithms, and the clinical factors associated with a favorable treatment response. Finally, we describe the clinical characteristics of patients who may benefit from these drugs.
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PMID:[Effects of GLP-1 receptor agonists on carbohydrate metabolism control]. 2543 61

Stanniocalcins are expressed in the pancreas tissue, and it was suggested a direct correlation between circulating insulin and STC2 concentrations in human. Here, we show a significant correlation between STC1 and both glycaemia and glycosylated haemoglobin among DM2 patients, while DM2 patients who present the greatest glycosylated haemoglobin values exhibited the lowest STC2 expression. However, treatment of patients with antiglycaemic drugs does not significantly modify the expression of both STCs. On the other hand, STC2-/- mice that exhibited neonatal and adult overweight further presented deregulated glycaemia when they were feed with a hypercaloric diet (breeding pellet, BP). This alteration is more evident at the early stages of the animal life. Deregulated glycaemia in these mice was confirmed using glucose oral test. In addition, STC2-/- mice present enhanced pancreas size; thus, the histological analysis reveals that WT mice respond to BP diet by increasing the size of the pancreatic islets through inducing cell division, and STC2-/- mice lack this compensatory mechanism. Contrary, BP fed STC2-/- mice show enhanced number of islets but of similar size than those fed with regular pellet. Histopathological analysis demonstrates tissue structure disruption and erythrocytes infiltrations in STC2-/- mice, possibly due to the stress evoked by the BP diet. Finally, enhanced glucagon immunostaining was observed in the islet of STC2-/- mice, and the glucagon ELISA assay confirmed the increase in the circulating glucagon. Summarizing, we present evidence of the role of STCs, mainly STC2, as a possible early marker during development of diabetes mellitus.
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PMID:Involvement of stanniocalcins in the deregulation of glycaemia in obese mice and type 2 diabetic patients. 2899 Mar 24


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