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)

Chlorpropamide alcohol flushing (CPAF) in non-insulin-dependent diabetics (NIDDs) has been reported to be associated with a lower tendency to develop late complications. The flush was thought to be mediated by enkephalins and prostaglandins. Early studies could not correlate CPAF to increased levels of acetaldehyde in blood and the flush was not regarded as an antabuse-like reaction. In this study, the increase of plasma acetaldehyde during the flush in 13 CPAF positive diabetics was significantly (P less than 0.005) higher than in the 13 CPAF negative diabetics during a CPAF challenge test. The increase of plasma acetaldehyde was reduced to the level of CPAF negative diabetics in three CPAF positive diabetics when they were exposed to alcohol without premedication with chlorpropamide and they did not flush. The normal breakdown of ethanol to acetic acid via acetaldehyde appears to be inhibited by chlorpropamide in the flushers. Acetaldehyde measurement is an objective method to study the chlorpropamide alcohol flush and it appears superior to the measurement of skin temperature.
Diabetes 1981 Sep
PMID:Increase of plasma acetaldehyde. An objective indicator of the chlorpropamide alcohol flush. 726 73

We examined the effect of aldehyde-modified matrix macromolecules on mesangial cell function in vitro, using incubated rat glomerular mesangial cells. Laminin and fibronectin were modified by incubation for 24 h with 50 mM glycolaldehyde (GA), a highly reactive cross-linking glycation product, with or without equimolar aminoguanidine. GA-modified laminin and fibronectin caused marked inhibition of cell adhesion. Cell spreading was reduced on the GA-modified laminin. In contrast, the GA-modified fibronectin had no effect on cell spreading. The study of thymidine incorporation by mesangial cells showed that the GA-modified fibronectin had a diminished mitogenic activity against cells. The content of advanced glycation end-product (AGE), which was determined by fluorescence at 370 nm excitation and 440 nm emission wavelength, increased and intermolecular cross-links appeared in the GA-modified proteins. To a large extent, aminoguanidine restored the structural alterations and functional deteriorations described above. We conclude that GA-modified matrix proteins diminish their functional properties against mesangial cells and affect cellular functions.
Diabetes Res Clin Pract 1994 Feb
PMID:Effects of aldehyde-modified proteins on mesangial cell-matrix interaction. 801 60

The oral ethanol loading test (0.5 g/kg body mass given as 40% solution) was carried out in 5 groups, each of 10 out-patients with non-insulin-dependent (type 2) diabetes before and after 10 days of treatment with one of the following sulphonylurea derivatives: tolbutamide (CAS 64-77-7) 0.5 t.i.d., chlorpropamide (CAS 94-20-2) 0.5 once daily morning, glibornuride (CAS 26944-48-9) 0.025 t.i.d., glibenclamide (CAS 10238-21-8) 0.005 t.i.d. and glipizide (CAS 29094-61-9) 0.005 t.i.d. The response to alcohol (facial flush, heart rate, blood pressure) were compared, and blood concentrations of ethanol, acetaldehyde, pyruvate, lactate, hydrocarbonates as well as blood pH, pO2 and pCO2 were determined in fasting state and during 6 hours after alcohol ingestion. In all patients the family history of diabetes and the presence and degree of vascular complications were registered. Evident flushing phenomenon was observed in 6 patients treated with chlorpropamide, in 3 treated with tolbutamide, in 2 treated with glibenclamide, in one receiving glibornuride and in none treated with glipizide. All drugs caused a greater rise of blood ethanol and acetaldehyde levels in relation to the control tests, but the difference reached statistical significance only in the group receiving chlorpropamide. Moreover, patients (pooled) with positive thermographic response had also significantly higher blood levels of ethanol and acetaldehyde during the second test. The ratio of acetaldehyde to ethanol concentration in blood (mumol:mmol) was not significantly changed in any group indicating parallel impairment of both steps of ethanol metabolism.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Alcohol tolerance in patients with non-insulin-dependent (type 2) diabetes treated with sulphonylurea derivatives. 805 71

The time-course of the reaction of H1 and total histone with glucose, acetaldehyde or both has been studied using the NBT reduction test and fluorescence. With both methods, purified H1 histone gave higher absorbance with acetaldehyde than with a 1:1 combination of glucose and acetaldehyde. For total histone, the opposite was found; a 1:1 combination of the above two aldehydes had the higher absorbance. As an explanation, the possibility of different reactivity of the amino groups with glucose and acetaldehyde is proposed. A possible simultaneous interaction between glucose, acetaldehyde and serum protein, mainly albumin, may alter the results of the diagnostic protein glycation methods, e.g. of the fructosamine test, and, therefore, also the monitoring of diabetes.
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PMID:The kinetics of the addition of glucose and acetaldehyde to histone proteins. 808 May 96

Highly purified islets of Langerhans were prepared in the present study from adult pigs by collagenase digestion and density gradient purification. After overnight culture, the tissue was equilibrated with DMSO at 25 degrees C, supercooled to -7.5 degrees C, nucleated, slowly cooled at 0.25 degrees C/min to -40 degrees C, and stored at -130 degrees C. Then, after variable periods of storage, the islets were rapidly thawed at 37 degrees C. Postthaw actual islet and islet equivalent (150-microns sized islets) recovery were 75 +/- 7% and 66 +/- 4%, respectively. The frozen-thawed porcine islets maintained good morphology on histological staining by hematoxylin-eosin and aldehyde-fuchsin. Upon perifusion, basal insulin secretion was 43 +/- 10 and 67 +/- 18 pmol/L from noncryopreserved, control islets, and cryopreserved islets, respectively (P = 0.2). Peak insulin release at 16.7 mmol/L glucose was 85 +/- 28 pmol/L from noncryopreserved islets and 157 +/- 48 pmol/L from the frozen-thawed islets (P = 0.1). When 10 mmol/L theophylline was added to 16.7 mmol/L glucose, the secretion of the hormone peaked to 221 +/- 83 (control islets) and 479 +/- 140 pmol/L (cryopreserved islets, P = 0.1). Total insulin secretion differed significantly for the noncryopreserved and the cryopreserved islets at both 16.7 mmol/L (1412 +/- 306 vs. 3756 +/- 764 pmol/L, respectively, P = 0.007) and 16.7 mmol/L glucose plus 10 mmol/L theophylline (2161 +/- 371 vs. 7505 +/- 2075 pmol/L, respectively, P = 0.011). Normoglycemia was restored within 7 days from implantation in temporarily immunosuppressed (aL3T4 antibody) mice with streptozotocin-induced diabetes by transplanting 1500-2000 cryopreserved porcine islets under the kidney capsule. Mean survival time of frozen-thawed islet xenografts (39 +/- 3 days) was similar to that of noncryopreserved islet xenografts (43 +/- 6 days). This study demonstrates that cryogenic storage is feasible of isolated porcine islets, with the frozen-thawed pancreatic endocrine tissue maintaining morphological integrity and both in vitro and in vivo viability. Further studies are needed to define the effect of cryopreservation on the immunogenic properties of porcine islets.
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PMID:Cryogenic storage of isolated, purified porcine pancreatic islets. 810 68

Mounting experimental evidence links increased aldose reductase activity with diabetes-related kidney functional changes. To investigate the interrelationship of NADPH-dependent reductases in the human kidney, both aldose reductase and aldehyde reductase were purified from human kidney by a series of chromatographic procedures, including gel filtration on Sephadex G-100, affinity chromatography on Matrex Gel Orange A, and chromatofocusing on Mono P. Each purified enzyme appeared as a single band on polyacrylamide gel after electrophoresis or isoelectric focusing. Aldose reductase has a pI of 5.7 and apparent molecular weight of 37 kDa, calculated from SDS-polyacrylamide gel electrophoresis, while aldehyde reductase has a pI of 5.2 and molecular weight of 39 kDa. Similar molecular weights were also obtained by gel filtration, indicating that both aldose and aldehyde reductases are present as monomers in the human kidney. Aldehyde reductase is primarily localized in the cortex, while the medulla contains aldose reductase. Both enzymes displayed properties consistent with the general characteristics of aldose and aldehyde reductases obtained from either rat or dog kidney. Purified aldose reductase utilizes aldose sugars such as D-xylose, D-glucose, and D-galactose as substrates while aldehyde reductase preferentially reduces D-glucuronate and oxidizes L-gulonate to D-glucuronate. Despite the lower apparent affinity of aldehyde reductase for aldose sugars (approximately 20- to 100-fold less) both enzymes reduced D-xylose, D-glucose, and D-galactose to their respective sugar alcohols in in vitro incubation studies where the generated sugar alcohols were identified by gas chromatography. Both enzymes were also inhibited by aldose reductase inhibitors.(ABSTRACT TRUNCATED AT 250 WORDS)
J Diabetes Complications
PMID:Human kidney aldose and aldehyde reductases. 834 12

The oral ethanol loading test (0.5 g per kg b.m. given as 40% solution) was carried out in 5 groups, each of 10 patients with non-insulin-dependent (type 2) diabetes before and after 10 days of treatment with one of the following sulphonylurea derivatives: tolbutamide 0.5 t.i.d., chlorpropamide 0.5 once daily morning, glibornuride 0.025 t.i.d, glibenclamide 0.005 t.i.d. and glipizide 0.005 t.i.d. The response to alcohol (facial flush, heart rate, blood pressure) were compared, and blood concentration of ethanol, acetaldehyde, pyruvate, lactate, carbonates as well as blood pH, pO2 and pCO2 were determined in fasting state and during 6 hours after alcohol ingestion. In all patients the family history of diabetes and the presence and degree of vascular complications were registered. Evident flushing phenomenon was observed in 6 patients treated with chlorpropamide, in 3 treated with tolbutamide, in 2 treated with glibenclamide, in one receiving glibornuride and in none treated with glipizide. All drugs caused a greater rise of blood ethanol and acetaldehyde levels in relation to the control tests, but the difference reached statistical significance only in the group receiving chlorpropamide. Moreover, patients (pooled) with positive thermographic response had also significantly higher blood levels of ethanol and acetaldehyde during the second test. The ratio of acetaldehyde to ethanol concentration in blood (mumol:mmol) was not significantly changed in any group indicating parallel impairment of both steps of ethanol metabolism. All studied drugs intensified to a similar degree the alcohol-induced hypoglycaemia, but had no significant effect on the decrease of blood pyruvate level neither on the increase of blood lactate level. They didn't change the post-alcohol decrease of blood bicarbonate and pH, and didn't modify the behaviour of partial gas pressure. There was also no difference between pooled groups of patients with positive and negative thermographic reaction with respect to family history of diabetes and frequency and intensity of vascular complications. It is concluded that in patients with non-insulin-dependent (type 2) diabetes the second generation sulphonylurea derivatives are associated with lower risk of alcohol intolerance in case of its incidental ingestion in small amounts. The hypothesis of association of positive thermographic reaction to alcohol during treatment with sulphonylurea derivatives with more frequent occurrence of diabetes in family members and lower tendency to vascular complications was not confirmed.
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PMID:[Alcohol tolerance in patients with non-insulin-dependent diabetes (type 2) treated orally with drugs--derivatives of sulphonylurea]. 841 9

We compared the distribution and density of ocular adrenergic nerves in rats after 3 to 13 months of streptozotocin diabetes and in age-matched control animals to learn whether diabetic sympathetic neuropathy is evident in the eye as it is in other organs. An aqueous aldehyde method for histochemical demonstration of catecholamines provided a clear and complete view of the adrenergic innervation in whole flat preparations of choroid and iris. In the choroid, a dense plexus of varicose nerve fibers invested all of the branching arterial blood vessels. A less dense network of nerves was present in the choroidal stroma between the arteries, but there was no obvious association of nerves with the venules draining choroidal capillaries. Using a stereological method to measure the density of the adrenergic plexus of choroidal arteries, we found the mean innervation density to be normal in diabetic animals sampled at 3, 9, and 13 months after onset of hyperglycemia. Microscopic examination also failed to reveal diabetes-associated changes in the diffuse stromal nerves of the choroid or in the rich adrenergic innervation of the iris. Diabetes of relatively long duration, therefore, does not obviously affect the density or distribution pattern of catecholamine-containing nerves supplying the rat eye.
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PMID:Adrenergic innervation of the choroid and iris in diabetic rats. 843 13

The widespread distribution of enzymes classed as semicarbazide-sensitive amine oxidases (SSAO enzymes) throughout a very wide range of eukaryotic as well as prokaryotic organisms encourages the aspirations of those who wish to demonstrate physiological, pathological or pharmacological importance. Such enzymes are found in several tissues of mammals, both freely soluble, as in blood plasma, and membrane-bound, for example, in smooth muscle and adipose tissue. While they are capable of deaminating many amines with the production of an aldehyde and hydrogen peroxide, doubt still surrounds the identity of the most important endogenous substrates for these enzymes. At present, methylamine and aminoacetone appear to head the list of candidates. The possibility that SSAO enzymes can convert amine substrates to highly toxic metabolites is illustrated by the production of acrolein from the xenobiotic amine, allylamine and formaldehyde and methylglyoxal from methylamine and aminoacetone, respectively. Activities of SSAO enzymes may be influenced by physiological changes, such as pregnancy or pathologically by disease states, including diabetes, tumours and burns. Increased deamination of aminoacetone by tissue and plasma SSAO enzymes as a result of its increased production from L-threonine in conditions such as exhaustion, starvation and diabetes mellitus may be harmful. Such dangers could be mitigated either physiologically by a compensatory reduction in SSAO activity or pharmacologically by treatment with inhibitors of SSAO.
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PMID:Some aspects of the pathophysiology of semicarbazide-sensitive amine oxidase enzymes. 858 67

Group B streptococci (GBS) are the major cause of serious infections in neonates and an important cause of infection in adults, particularly peripartum women and patients with diabetes mellitus and malignancy. Immunity to GBS in neonates is associated with naturally acquired maternal antibodies to the type-specific capsular polysaccharides of these organisms. IgG class antibodies directed to these polysaccharides are passed transplacentally and protect the child from invasive GBS disease. Phase I and II clinical trials showed that the purified polysaccharides had limited immunogenicity. However, vaccine responders passed functional IgG class antibodies to their children. A glycoconjugate vaccine has been designed so that the type-specific polysaccharides are covalently linked to a carrier protein. This secondary amine linkage is between aldehyde groups created on the eighth carbon of a selected number of periodate-oxidized sialic acid residues of the polysaccharide and epsilon-amino groups on lysine residues of tetanus toxoid. Careful epitope mapping studies had demonstrated that modification by controlled periodate oxidation could be accomplished and that an important conformational epitope on the polysaccharide would be preserved. Preclinical testing of the glycoconjugate vaccines in animal models of GBS disease demonstrated the immunogenicity and protective efficacy of the vaccine-induced antibodies. Phase I clinical testing of the glycoconjugate vaccine is in progress, and the early results appear promising.
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PMID:Designer vaccines to prevent infections due to group B Streptococcus. 860 25


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