Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011860 (type 2 diabetes)
 57,723 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Amylin, also called islet amyloid polypeptide (IAPP), or diabetes-associated peptide (DAP) is a recently discovered 37 amino acid polypeptide which has been shown to be co-secreted with insulin from the pancreatic beta-cell. The peptide turned out to be the major constituent of pancreatic amyloid deposits which are frequently found in the pancreas of type II diabetic patients. Therefore, a role for amylin in the aetiology of type II diabetes was hypothesized. To investigate this possibility, several studies have been performed to elucidate whether amylin is able to impair insulin secretion and action, two characteristic features of type II diabetes mellitus. These studies suggest that it is unlikely that amylin has a direct inhibitory effect on insulin secretion. Amyloid deposits, however, which are derived from the in situ polymerization and precipitation of amylin, may impair beta-cell function during type II diabetes by damaging and covering beta-cells. Furthermore, it has been shown that amylin has the potential to antagonize the action of insulin on glucose metabolism by increasing hepatic glucose production and by decreasing muscle, but not adipocyte glucose uptake. For these reasons, it has been suggested that amylin might be involved in the pathophysiology of type II diabetes and obesity, disease states which are characterized by abnormal beta-cell function and insulin resistance. In addition, amylin was shown to induce hypocalcaemia by inhibiting osteoclast-mediated bone resorption in a calcitonin-like manner. Therefore, amylin is likely to be involved in both the modulation of glucose and calcium metabolism.
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PMID:Biological action of pancreatic amylin: relationship with glucose metabolism, diabetes, obesity and calcium metabolism. 140 45

Twenty-five middle-aged subjects with impaired glucose tolerance (IGT) were analysed 5 years later, showing normal glucose tolerance in 28% and persistent glucose deterioration in 72%. Body mass index (strongly) and 2-h glucose levels were clinically useful predictors, in the newly detected IGT-subjects, of persistent glucose deterioration (IGT or NIDDM) 5 years later. The frequency of hypertension was 36% in the newly-detected IGT subjects. Five years later this frequency increased to 54% in the persistently hyperglycaemic group, and decreased to none in the normalized group. Predictors of hypertension at the follow-up were baseline blood pressure and parts of the hyperinsulinaemic syndrome, such as serum triglyceride at baseline, BMI and 2-h glucose at the follow-up. Microalbuminuria (greater than 20 mg day-1) was not found at the 5-years follow-up, either if the subjects then had NIDDM, IGT or normal glucose tolerance. ECG abnormalities (ST segment and T wave changes) were two-fold more prevalent in the group with IGT or NIDDM than in the normalized group at the follow-up. Predictors were baseline BMI and incremental BMI. In conclusion, obesity and high 2-h glucose in newly-detected IGT-subjects seemed to predict the persistence of IGT 5 years later. Hypertension, but not microalbuminuria, was frequent when glucose deterioration persisted.
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PMID:What causes impaired glucose tolerance to deteriorate or normalize? 141 Dec 61

The effect of glycaemic control on the early morning plasma glucose rise, 'the dawn phenomenon', was assessed in two matching diabetic patient groups each comprising five NIDDM and two IDDM patients per group, who were otherwise considered to be in poor (HbA1 = 11.2 +/- 0.6%) or good (HbA1 = 7.6 +/- 0.2%) glycaemic control. Hourly plasma concentrations of glucose, insulin, glucagon, cortisol, and growth hormone were measured between 03.00 and 09.00 h. In all the poorly controlled diabetic patients the mean rise in plasma glucose between 06.00-08.00 and 03.00 h was greater than or equal to 1.0 mmol/l. In contrast, the plasma glucose increment was less than 1.0 mmol/l in the well controlled diabetics. The overnight mean insulin levels in the poor and well controlled patient groups were 19.3 +/- 0.5 and 25.0 +/- 0.6 mU/l (P less than 0.001) respectively. Glucagon, cortisol, and growth hormone levels in the early morning showed no significant differences between the two groups. The decline in plasma insulin from 03.00 to 08.00 h and mean cortisol level between 03.00 and 06.00 h were both significantly correlated with the increase in plasma glucose between 03.00 and 08.00 h. We concluded that an increase of 1.0 mmol/l or more in plasma glucose during the early morning is of clinical importance.
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PMID:The dawn phenomenon and diabetes control in treated NIDDM and IDDM patients. 142 38

First-degree relatives of patients with NIDDM manifest severe insulin resistance despite normal glucose tolerance test. To examine the mechanisms underlying the normal glucose tolerance, we evaluated the serum glucose/C-peptide/insulin dynamics and free fatty acid (FFA) as well as substrate oxidation rates and energy expenditure (EE) (indirect calorimetry) in nine young offspring of NIDDM patients (mean +/- SEM age 30 +/- 2.3 years, body mass index 24.2 +/- 1.2 kg/m2). Nine age-, sex- and weight-matched, normal subjects with no family history of diabetes served as the controls. Metabolic parameters were measured before, during and after a two-step glucose infusion (2 and 4 mg/kg.min) for 120 min. Mean basal serum glucose, insulin and C-peptide levels were similar in both groups. During 2 mg/kg.min glucose infusion, mean serum insulin and C-peptide rose to significantly (P less than 0.05-0.02) greater levels in the offspring vs. controls, while serum glucose levels were similar. With the 4 mg/kg.min glucose infusion, mean serum glucose, insulin and C-peptide levels were significantly (P less than 0.02-0.001) greater in the offspring at 100-120 min. Isotopically-derived (D[3-3H]glucose), basal hepatic glucose output (HGO) was not significantly different between the offspring vs. controls (1.86 +/- 0.30 vs. 1.78 +/- 0.06 mg/kg.min). During glucose infusion, basal HGO was partially suppressed by 66% at 60 min and by 100% at 120 min in the offspring. In contrast, HGO was completely (100%) suppressed at both times in the controls. Following cessation of glucose infusion, HGO rose to 1.64 +/- 0.12 mg/kg.min in the offspring and 1.46 +/- 0.05 mg/kg.min in the controls (P less than 0.05) between 200 and 240 min. These were 88% and 82% of the respective basal HGO values. At low glucose infusion (t = 0-60 min), the mean absolute, non-oxidative glucose disposal remained 1.5-fold greater in the offspring while at higher glucose infusion, nonoxidative glucose metabolism was not different in both groups. Throughout the study period, oxidative glucose disposal rate was not significantly different in both groups. The mean basal FFA was significantly greater in the offspring vs. controls (865 +/- 57 vs. 642 +/- 45 microEq/l). It was appropriately suppressed during glucose infusion to a similar nadir in both groups (395 +/- 24 vs. 375 +/- 33 microEq/l). The mean basal lipid oxidation was also significantly greater in the offspring than controls (1.06 +/- 0.05 vs. 0.75 +/- 0.04 mg/kg.min, P less than 0.05).(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:The effects of superphysiologic hyperinsulinemia on glucose and lipid metabolism in glucose-tolerant offspring of patients with non-insulin-dependent diabetes mellitus (NIDDM). 142 56

The aim of the present study was to identify in young, diabetes-prone subjects the early abnormalities which may predispose to the development of type 2 diabetes. We studied 10 full-blood Australian Aborigines all of whom had a family history of diabetes and who were from an urbanised community with a high prevalence of this disorder. They were compared to 10 age- and body-mass-index-matched Caucasian controls with no family history of diabetes. Glucose kinetics were measured basally and following an oral glucose load. Fasting plasma glucose was equal in the two groups, but 2 h following the 75 g glucose load, the Aboriginal subjects had higher glycaemia than the controls (P less than 0.01). Insulinaemia was higher in the Aborigines both basally and following the glucose drink (P less than 0.05). Despite the hyperinsulinaemia, hepatic glucose production was higher in the Aboriginal subjects (P less than 0.01), while metabolic clearance rate was lower. It is concluded that in young Australian Aborigines with a strong family history of type 2 diabetes, both hepatic and peripheral insulin resistance are early abnormalities.
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PMID:Identification of early metabolic defects in diabetes-prone Australian aborigines. 142 61

The effect of insulin on the serum levels of the amino-terminal propeptide of type III procollagen (PIIINP) was investigated in patients with non-insulin-dependent diabetes mellitus, whose disease was unsatisfactorily controlled by oral drugs. Before insulin therapy the PIIINP values of the patients (3.2 +/- 1.3 micrograms/l, n = 38) varied within the range of healthy subjects (3.1 +/- 0.6 micrograms/l, n = 50, NS). Insulin therapy (6-20 IU at bedtime plus the oral drugs) improved the glycemic control and increased the serum PIIINP during a 4 week (3.1 +/- 0.9 to 3.8 +/- 1.1 micrograms/l, P less than 0.01, n = 8) and an 8 week period (3.2 +/- 1.3 to 3.8 +/- 1.6 micrograms/l, P less than 0.001, n = 22). The values were still elevated after 6 months on insulin (3.5 +/- 1.5 to 4.0 +/- 1.7 micrograms/l, P less than 0.01, n = 12). Placebo-insulin did not alter the concentration of PIIINP (3.1 +/- 0.6 to 2.8 +/- 0.6 micrograms/l, NS, n = 8) whereas the glycemic control improved and body weight decreased. The PIIINP values correlated with fasting insulin before (r = 0.403, P less than 0.05, n = 30) and after the therapy (r = 0.452, P less than 0.001, n = 60). Insulin therapy, while correcting the hormone deficiency and restoring glucose and protein metabolism, seems to activate the synthesis of type III procollagen in patients with NIDDM. This may promote the atherosclerotic process.
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PMID:Effect of insulin on serum amino-terminal propeptide of type III procollagen in non-insulin-dependent diabetes mellitus. 142 60

The entry of glucose into muscle cells is achieved primarily via a carrier-mediated system consisting of protein transport molecules. GLUT-1 transporter isoform is normally found in the sarcolemmal (SL) membrane and is thought to be involved in glucose transport under basal conditions. With insulin stimulation, glucose transport is accelerated by translocating GLUT-4 transporters from an intracellular pool out to the T-tubule and SL membranes. Activation of transporters to increase the turnover number may also be involved, but the evidence is far from conclusive. When insulin binds to its receptor, it autophosphorylates tyrosine and serine residues on the beta-subunit of the receptor. The tyrosine residues are thought to activate tyrosine kinases, which in turn phosphorylate/activate as yet unknown second messengers. Insulin receptor antibodies, however, have been reported to increase glucose transport without increasing kinase activity. Insulin resistance in skeletal muscle is a major characteristic of obesity and diabetes mellitus, especially NIDDM. A decrease in the number of insulin receptors and the ability of insulin to activate receptor tyrosine kinase has been documented in muscle from NIDDM patients. Most studies report no change in the intracellular pool of GLUT-4 transporters available for translocation to the SL. Both the quality and quantity of food consumed can regulate insulin sensitivity. A high-fat, refined sugar diet, similar to the typical U.S. diet, causes insulin resistance when compared with a low-fat, complex-carbohydrate diet. On the other hand, exercise increases insulin sensitivity. After an acute bout of exercise, glucose transport in muscle increases to the same level as with maximum insulin stimulation. Although the number of GLUT-4 transporters in the sarcolemma increases with exercise, neither insulin or its receptor is involved. After an initial acute phase, which may involve calcium as the activator, a secondary phase of increased insulin sensitivity can last for up to a day after exercise. The mechanism responsible for the increased insulin sensitivity with exercise is unknown. Regular exercise training also increases insulin sensitivity, which can be documented several days after the final bout of exercise, and again the mechanism is unknown. An increase in the muscle content of GLUT-4 transporters with training has recently been reported. Even though significant progress has been made in the past few years in understanding glucose transport in skeletal muscle, the mechanisms involved in regulating transport are far from being understood.
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PMID:Regulation of glucose transport in skeletal muscle. 142 62

Insulin resistance and glucose intolerance are common features of polycystic ovary syndrome (PCOS). We have investigated the effect of glucose on the fractional glucose disappearance in patients with PCOS and in age- and weight-matched control subjects. The minimal model method as applied to a frequently sampled intravenous glucose tolerance test was employed. The insulin sensitivity index (Si) and glucose effectiveness (SG) were calculated with the MINMOD program. Testosterone, androstenedione and free testosterone concentrations were significantly higher in PCOS subjects. Glucose-induced glucose clearance (SG) and insulin sensitivity were significantly lower in PCOS subjects than controls [SG: 2.7 +/- 0.3 versus 1.8 +/- 0.1 x 100/min; P less than 0.01; Si: 133.4 +/- 20.0 versus 65.6 +/- 6.4/min (nmol/ml)]. Six PCOS women had an SG value within the normal range (greater than 2.0 x 100/min) but had a similar Si to that found in PCOS women with abnormal SG. We suggest that independent alterations in both glucose- and insulin-mediated glucose uptake occur in patients with PCOS. The underlying disturbance in glucose effectiveness may be similar to that found in familial non-insulin dependent diabetes mellitus.
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PMID:Impaired glucose effectiveness in patients with polycystic ovary syndrome. 143 Jan 29

Parameters of blood glucose control and insulin secretion were evaluated in 114 patients with type 2 diabetes mellitus, who were no longer controlled satisfactorily by maximal doses of oral hypoglycaemic agents, and compared with those obtained in 11 healthy control subjects, 32 patients with recently-diagnosed type 2 diabetes, and 16 tablet-treated and 36 insulin-treated patients. Newly-diagnosed patients were slightly younger (60 +/- 13 yr) and had a slightly higher body mass index (29.4 +/- 6.5 kg/m2). Known duration of diabetes was 9 yr (range 1-37) in secondary failure, and 11 yr (range 1-31) in insulin-treated patients. Fasting blood glucose was the highest (13.8 +/- 2.8 mmol/l) in secondary failure and newly-diagnosed patients (12.6 +/- 3.8 mmol/l) compared to tablet-treated (8.7 +/- 3.3 mmol/l) and insulin-treated patients (9.6 +/- 3.2 mmol/l, p less than 0.05). HbA1c levels were comparably elevated. In insulin-treated patients, fasting plasma C-peptide levels were lower relative to the mutually comparable levels in the other 3 diabetic groups. Fasting plasma insulin levels did not differ between the 4 diabetic groups. C-peptide release after glucagon (C-peptide AUC) was comparable in all 4 diabetic groups, although in tablet-treated patients the ratio C-peptide AUC/fasting blood glucose was higher (p less than 0.05). We conclude that the clinical usefulness of determining residual insulin secretion in type 2 diabetic patients is limited, and that the similar reduction of insulin secretion in severely hyperglycaemic newly-diagnosed and secondary failure type 2 diabetic patients supports the concept of "glucose toxicity".
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PMID:Glucagon-stimulated insulin secretion in patients with type 2 diabetes mellitus: support for the concept of glucose toxicity. 143 66

The relationship between obesity and type II diabetes mellitus is well established and a majority of type II diabetic individuals are classified as obese. The pathogenesis of type II diabetes mellitus is not fully understood; however, multiple organ systems are involved, including abnormalities of insulin secretion, peripheral insulin resistance and hepatic insulin resistance. The goal of the treatment for the obese diabetic is to normalise these alterations and achieve normoglycaemia. Traditionally, the initial therapy, aiming to accomplish weight reduction, is diet and exercise. In obese type II diabetic patients, the whole body insulin-dose response curve is markedly depressed. A single exercise session improves and partially normalises both insulin responsiveness and sensitivity for glucose utilisation. Furthermore, a single bout of physical activity often results in decreased plasma glucose levels, which persists into the postoperative period. Type II diabetes patients participating in regular exercise programmes can potentially improve their metabolic control. An improved glucose control in both lean and obese type II diabetic patients under the age of 55 years has been demonstrated by improved HbA1C levels and glucose tolerance tests following physical training programmes. The effect of regular exercise on the metabolic control in these younger patients does not appear to be correlated with weight reduction. For most type II diabetic men over 55 years of age, physical training is not a feasible form of therapy because of other interfering diseases which may complicate or severely hinder all physical training apart from very low intensity exercise programmes. Lean, older, type II diabetic patients who have been able to exercise for 10 weeks or up to 2 years demonstrate no change in HbA1C levels, glucose tolerance or bodyweight. Thus, there is a clear difference in metabolic response to regular exercise between younger and older type II diabetic patients. The younger patient appears to be more inclined to respond to physical training with improvements in the metabolic control. The reason for this apparent difference is not clear, but possible explanations may include differences in training intensity, the presence or degree of complicating diseases, pretraining level of metabolic control or bodyweight. Type II diabetics are predisposed to cardiovascular disease and are characterised by hyperlipidaemia. In obese type II diabetic individuals, physical training improves the blood lipid profile as measured by decreased levels of triglycerides and total cholesterol. In young, overweight diabetics, improved lipid profiles can be achieved despite no change in bodyweight, while no apparent effects are reported for lean patients.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Exercise training in obese diabetic patients. Special considerations. 143 93


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