Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011849 (diabetes)
 277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Defective glucose counterregulation commonly seen in intensively treated insulin-dependent diabetes (IDDM) is mediated in part by a failure of compensatory stimulation of hepatic glucose production. Since the response of the liver to insulin-induced hypoglycemia normally involves activation of gluconeogenesis, we measured [14C]alanine conversion to [14C]glucose (a qualitative index of gluconeogenesis) and glucose production (using [3-3H]glucose) in seven intensively treated type I diabetic subjects (hemoglobin-A1, 7.1 +/- 0.4%) during low dose infusion of insulin (0.3 mU/kg.min for 210 min). IDDM patients received insulin overnight to maintain euglycemia before study. Although insulin levels rose to a similar extent as those in normal control subjects (n = 6), the fall in plasma glucose was markedly greater in IDDM (2.5 +/- 0.2 vs. 3.64 +/- 0.2 mM in controls; P < 0.01). The glucagon response was totally lost in IDDM, and epinephrine release was delayed and slightly reduced compared to that in control subjects. In contrast to that in normal subjects, hepatic glucose production in the IDDM subjects remained persistently suppressed by about 60% throughout the study. The conversion of alanine and lactate to glucose remained virtually unchanged in the IDDM, whereas in controls it increased 2-fold above baseline during the last hour of the study. Our data suggest that the failure of gluconeogenesis to increase during hypoglycemia is an important factor contributing to the defective hepatic response observed in the intensively treated type I diabetic subjects.
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PMID:Impaired stimulation of gluconeogenesis during prolonged hypoglycemia in intensively treated insulin-dependent diabetic subjects. 140 Aug 74

Abnormal amino acid metabolism is sometimes observed among patients with diabetes mellitus. Of many amino acids, alanine and branched-chain amino acids such as valine, leucine, isoleucine show characteristic changes. In diabetic ketoacidosis, plasma concentration of alanine decreases and that of branched-amino acid increases and the oxidation of branched-amino acids is enhanced. Splanchnic amino acid uptake is generally higher in diabetics and this level is partially restored by exercise. Some glycosylated proteins are used to estimate the condition of diabetes mellitus. Increment of urinary glycosylated amino acid excretion is reported in diabetics. Plasma homocysteine, reactive vascular-injuring amino acid, increases in diabetics with nephropathy. Those abnormal amino acid metabolism would be restored after good glycemic control is obtained.
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PMID:[Abnormal amino acid metabolism in diabetes mellitus]. 140 95

It is generally believed that glucose production (GP) cannot be adequately suppressed in insulin-treated diabetes because the portal-peripheral insulin gradient is absent. To determine whether suppression of GP in diabetes depends on portal insulin levels, we performed 3-h glucose and specific activity clamps in moderately hyperglycemic (10 mM) depancreatized dogs, using three protocols: (a) 54 pmol.kg-1 bolus + 5.4 pmol.kg-1.min-1 portal insulin infusion (n = 7; peripheral insulin = 170 +/- 51 pM); (b) an equimolar peripheral infusion (n = 7; peripheral insulin = 294 +/- 28 pM, P < 0.001); and (c) a half-dose peripheral infusion (n = 7), which gave comparable (157 +/- 13 pM) insulinemia to that seen in protocol 1. Glucose production, use (GU) and cycling (GC) were measured using HPLC-purified 6-[3H]- and 2-[3H]glucose. Consistent with the higher peripheral insulinemia, peripheral infusion was more effective than equimolar portal infusion in increasing GU. Unexpectedly, it was also more potent in suppressing GP (73 +/- 7 vs. 55 +/- 7% suppression between 120 and 180 min, P < 0.001). At matched peripheral insulinemia (protocols 2 and 3), not only stimulation of GU, but also suppression of GP was the same (55 +/- 7 vs. 63 +/- 4%). In the diabetic dogs at 10 mM glucose, GC was threefold higher than normal but failed to decrease with insulin infusion by either route. Glycerol, alanine, FFA, and glucagon levels decreased proportionally to peripheral insulinemia. However, the decrease in glucagon was not significantly greater in protocol 2 than in 1 or 3. When we combined all protocols, we found a correlation between the decrements in glycerol and FFAs and the decrease in GP (r = 0.6, P < 0.01). In conclusion, when suprabasal insulin levels in the physiological postprandial range are provided to moderately hyperglycemic depancreatized dogs, suppression of GP appears to be more dependent on peripheral than portal insulin concentrations and may be mainly mediated by limitation of the flow of precursors and energy substrates for gluconeogenesis and by the suppressive effect of insulin on glucagon secretion. These results suggest that a portal-peripheral insulin gradient might not be necessary to effectively suppress postprandial GP in insulin-treated diabetics.
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PMID:Importance of peripheral insulin levels for insulin-induced suppression of glucose production in depancreatized dogs. 143 Feb 3

This study was initiated to explore the possibility that an increase in the supply of gluconeogenic precursors contributes to the overproduction of glucose by the liver in NIDDM patients. To address this issue, a form of experimental NIDDM was produced in rats by injecting a low dose (38 mg/kg) of STZ and comparing lactate and alanine production and PDH activity in skeletal muscle and isolated adipocytes from normal and diabetic rats. Skeletal muscle lactate production was measured by using a hindlimb perfusion technique and was significantly greater (P < 0.01) in the diabetic rats compared with two groups of control rats: one perfused at normal glucose levels and the other perfused at glucose concentrations comparable with those observed in diabetic rats. Alanine production by hindlimb from diabetic rats was 46% greater than hindlimbs from control rats perfused at normal glucose levels (P < 0.01) but was not significantly greater than control rats perfused at diabetic glucose levels. The percentage of glucose converted to lactate by muscle from both control groups was 4-5%, significantly lower than the 18% conversion rate observed in diabetic animals (P < 0.001). An increase in the ratio of lactate produced/glucose transport by isolated adipocytes from diabetic rats also was observed when measured in both the basal state (0.65 +/- 0.12 vs. 0.15 +/- 0.03, P < 0.01) and in the presence of maximal amounts of insulin (0.15 +/- 0.02 vs. 0.04 +/- 0.01, P < 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)
Diabetes 1992 Dec
PMID:Lactate production and pyruvate dehydrogenase activity in fat and skeletal muscle from diabetic rats. 144 95

Genetic susceptibility alleles have been identified at the DQ HLA region. The aim of the present study was to confirm the value of these markers, and to evaluate the respective weight in the risk of the different alleles at the DQA1 and DQB1 levels, identified by restriction mapping after polymerase chain reaction on exon 2. A significant enrichment in DQB1 alleles encoding for an aminoacid different from Aspartic acid at position 57 (NA) was observed in diabetic (n = 213) in comparison to control (n = 93) children (94% vs 52%; p < 10(-8)). Not all the given NA/NA allelic combinations were equally and positively associated to the disease. Homozygous "Ala/Ala" combinations carried the highest relative risk (OR = 12.3; p < 10(-8)), and among them, the *0201/*0302 genotype was more positively associated to type 1 diabetes (OR = 66; p < 10(-8)). A significant enrichment in DQA1 alleles encoding for Arginine at position 52 in diabetic children was also observed (82% vs 40%; p < 10(-8)). The *0301/*0501 (Arg/Arg) genotype was significantly associated to Type 1 diabetes (OR = 16.2; p < 10(-4)). The highest risk was carried by the whole genotype, a result which could be expected from the known linkage desequilibrium between HLA-DQA1 and DQB1, DRB1 loci. The frequency of Ala DQB1 alleles was low in the background non-at-risk population, although the incidence of the disease is low in our country.
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PMID:[Respective weight of genotypes DQA1 and DQB1 associated with insulin-dependent diabetes in French children]. 145 18

The metabolic effects of 52 weeks treatment with the aldose reductase inhibitor ponalrestat were examined in 32 diabetic patients (16 insulin treated) in a randomized, double-blind, placebo-controlled clinical trial. Twelve hour metabolic profiles were performed on two separate occasions in each patient (a) during a single-blind placebo run-in period and (b) after 52 weeks treatment with either ponalrestat 600 mg/day or matching placebo. No effects attributable to ponalrestat were evident in glucose, pyruvate, or alanine metabolism. A significant overall treatment effect was observed for lactate concentration (ponalrestat vs. placebo 12 h least square mean at 52 weeks: 1.35 vs. 1.65 mmol/l, p = 0.024). For glycerol (p = 0.018), non-esterified fatty acids (p = 0.003) and total ketone bodies (p = 0.045) there was evidence for a variation of treatment with time between the insulin treated and non-insulin treated patients, although no statistically significant overall treatment effects were observed for any metabolite. Fasting total ketone body concentration at 52 weeks was significantly elevated in the insulin-treated patients receiving ponalrestat (antilog LS mean: 0.12 vs. 0.01 mmol/l, p = 0.01). In conclusion, ponalrestat has no effect on glucose metabolism in diabetic patients. A potentially beneficial effect on lactate metabolism was accompanied by a minor ketogenic effect in insulin-treated patients.
Diabetes Res 1992 Jan
PMID:Metabolic effects of aldose reductase inhibition in diabetic man. 146 86

Perioperative metabolism was evaluated in diabetic patients and animal models. Experimental model of diabetes mellitus (DM) model was obtained by streptozotocine injection. Each 14C-labeled substrates and combination of carbohydrates mixture was administered intravenously in a dose of 1 g/kg before and after laparotomy and cumulative curves of expired 14CO2 was calculated. Biochemical analysis in the liver, blood and urine were performed following infusion of two different solutions, GFX (glucose, fructose, xylitol) solution, 4:2:1 ratio by weight vs. glucose solution, with 12% amino acids solution. In a clinical study, incidence of DM in digestive surgery was examined in 3481 cases. Retrospective evaluation of GFX solution was performed in cases after total gastrectomy. Incidence of DM was 14% and it has been increased recently, Glucose metabolism in DM rats was disturbed after surgery. Amino acids (alanine and valine) and lipid metabolism was slightly suppressed after surgery in DM rats. The best combination of carbohydrate mixture was determined as GFX solution in animal and clinical experiments. GFX solution improved not only glucose metabolism but also lipid and amino acid metabolism in DM rats. Decreased insulin requirement and increased total caloric intake were observed in DM and borderline DM cases treated by GFX solution.
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PMID:[Therapeutic inventions of perioperative metabolic care in diabetic patients]. 147 Jan 64

Content of cytochromes P450 and b5, activities of amidopyrine-N-demethylase, alanine- and p-nitrophenol hydroxylases, NADPH-cytochrome c reductase were studied in the liver, kidney, small intestine and lung tissues of rats and rabbits in insulin-dependent hypoglycemia and alloxan diabetes. The diabetes and hypoglycemia caused dissimilar alterations in activity of alanine- and p-nitrophenol hydroxylases, thus indicating their dependence on blood sugar levels. The activity of monooxygenase enzymes studied was altered similarly in rabbit liver and other tissues, while the enzymatic activity was distinctly differentiated in rat tissues. Specific properties of cytochromes P450 isozyme spectra appear to be responsible for these alterations detected.
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PMID:[Status of the monooxygenase enzyme system in rat and rabbit organs in sugar diabetes and upon insulin administration]. 149 3

Twelve subjects with insulin-dependent diabetes mellitus were treated using continuous subcutaneous insulin infusion (CSII) and intraportal insulin infusion (IPII) via the umbilical vein for 4 mo. Glucose control improved in both CSII and IPII groups, but a decrease in glucose and HbAIc was more rapid and more significant in the IPII group than in CSII, even though insulin requirement was lower during IPII than CSII (40 +/- 2 vs. 50 +/- 2 U/day, P less than 0.05). The insulin plasma fasting levels were different (88 +/- 10.7 in the IPII group vs. 263 +/- 23 pM in CSII, P less than 0.001). High plasma levels of lactate, pyruvate, alanine, cortisol, and growth hormone were decreased in both groups, with their full normalization only in the IPII group. Glucagon concentrations were low in both groups at the beginning of the study (30.0 +/- 4.1 in the CSII group and 32.3 +/- 1.8 ng/L in IPII); they were equalized to control values in the IPII group and were low in the CSII group at the study's end (46.0 +/- 3.7 in IPII vs. 31.7 +/- 3.1 ng/L in CSII, P less than 0.05. We conclude that intraportal administration of insulin via the umbilical vein at rates of 0.01-0.05 U.kg-1.hr-1 reduces plasma levels of glucose, three carbon precursors, cortisol, and growth hormone by a direct action on the liver, and the hepatic action of peripherally administered insulin is manifested only when the infusion rate is increased to 0.1-0.3 U.kg-1.hr-1.(ABSTRACT TRUNCATED AT 250 WORDS)
Diabetes 1992 Sep
PMID:Comparison of peripheral and portal (via the umbilical vein) routes of insulin infusion in IDDM patients. 149 56

Glucose homeostasis is physiologically maintained by the balance between glucose production by the liver and glucose utilization by the peripheral tissues. Insulin controls hepatic glucose production and promotes glucose utilization by the skeletal muscle. In non-insulin-dependent diabetes mellitus (NIDDM), postabsorptive hepatic glucose production is increased and exhibits a positive correlation with fasting plasma glucose concentration. This increase in hepatic glucose production is the main cause of fasting hyperglycemia in NIDDM. Between the two processes by which the liver produces glucose (gluconeogenesis and glycogenolysis), gluconeogenesis appears to be drastically increased in NIDDM. The increase in gluconeogenesis accounts for most of the increased hepatic glucose production in this condition, and a positive correlation has been found in NIDDM subjects between the rates of gluconeogenesis and fasting plasma glucose concentration. Increased production of gluconeogenic precursors (lactate, alanine, glycerol) fuels this increased gluconeogenesis, but some type of intrahepatic mechanism is also present in NIDDM that increases the hepatic conversion of these substrates into glucose. Hyperglucagonemia and increased hepatic free fatty acid oxidation might be responsible for this increase hepatic gluconeogenic efficiency in NIDDM. Reduced suppression of hepatic glucose production after carbohydrate ingestion also plays an important role in the impairment in postprandial glucose homeostasis in NIDDM. In NIDDM subjects splanchnic extraction of an oral glucose load is not decreased, but hepatic glucose production is suppressed less than in nondiabetic subjects after the load. Residual hepatic glucose production after glucose ingestion is also correlated with fasting plasma glucose in NIDDM. Preliminary data suggest that in the postprandial state increased gluconeogenesis represents the primary mechanism responsible for impaired suppression of hepatic glucose production. Given the primary role of increase hepatic gluconeogenesis in the pathogenesis of hyperglycemia in NIDDM, development of new drugs aimed at correcting the factors that might cause increased gluconeogenesis (e.g., increased free fatty acid oxidation and hyperglucagonemia) might open the way for new form of treatment of this disorder.
Diabetes Care 1992 Mar
PMID:Role of liver in pathophysiology of NIDDM. 155 10


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