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)

Phase three of the Quebec Cooperative Study of Friedreich's Ataxia was devoted to an understanding of the physiopathology of individual symptoms on the basis of previously discovered biochemical leads. The present paper attempts to pull these results together by presenting, as a hypothesis, a unifying scheme of possible interactions and relationships. The central core of this hypothesis is the demonstration in Friedreich's ataxia of a state of mitochondrial energy deprivation. This is indirectly responsible for such associated and important symptoms as muscle weakness, dying-back neuropathy, scoliosis and hypertrophic cardiomyopathy. Secondarily, and possibly as an independent but linked-event, the entry of glucose into cells and pyruvate oxidation, are slowed down, favoring the development of diabetes. As a consequence, tissue concentrations of glutamic acid and aspartic acid are decreased, particularly in more vulnerable areas such as the cerebellum, brain stem and dorsal root ganglia. This tissue deficiency in putative excitatory neurotransmitters is directly responsible for the symptom of ataxia. This conclusion is reinforced by the correction of the ataxia in experimental animals, by the intraventricular injection of the same amino acids, and not by the injection of other stimulants of motricity. The observed mitochondrial energy deprivation could be the metabolic consequence of major changes in the linoleic acid (18.2) composition of inner mitochondrial membrane phospholipids, such as cardiolipin. Such decreases in membrane 18:2 could be the result of interference with the normal incorporation of this fatty acid to lipoproteins and/or cell membranes. It is at this level that the search for the specific enzyme defect in Friedreich's ataxia is continuing.
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PMID:Friedreich's ataxia 1980. An overview of the physiopathology. 678 90

Blood-borne free amino acids of 100 mothers were tested immediately after birth. Fifty of the probands had diabetes, while the other 50 were metabolically intact. Amino acid imbalance was recorded by means of multidimensional variance analysis from the diabetics and found to have been largely associated with glutamic acid threonine, alanine, glycine-serine, and glutamine.--A formula, derived from the aforementioned relevant amino acid concentrations, is given in this paper together with a nomogram (which might be used instead of the formula) for determination of diabetes-caused alterations in the amino acid spectrum
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PMID:[Amino acid imbalances in blood of pregnant women with diabetes and in blood of their newborns--limit values for screening (author's transl)]. 681 May 83

The modification of haemoglobin A by glucose to haemoglobin A Ic is a classical example for a nonenzymatic glucosylation (n. e. glu.) reaction of a protein. It has been suggested, that various proteins are subjected to this process during hyperglycemia phases, if the protein meets certain steric, electrostatic and biochemical characteristics. In the present report n. e. glu. of haemoglobin, serum protein, collagen, basement membrane protein and alkaline phosphatase is discussed. It is suggested that n. e. glu. might influence protein function and forms thus the biochemical basis for specific complications of diabetes mellitus in an outside pregnancy.
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PMID:[Non-enzymatic glucosylation of proteins]. 709 97

Free amino acids were studied in the blood of 50 newborns each of women with intact metabolism and of diabetic mothers. The tests were conducted immediately after delivery and on the fifth day of age. Amino acid imbalance reflected, after birth, in changed concentrations of glutamic acid-threonine, alanine and glycin-serine was recordable from newborns of the diabetic mothers. However, nothing but significant changes in concentrations of glutamic acid-threonine and alanine was recordable on the fifth day of age. --An account is given of the formulae and nomograms (applicable instead of these formulae) for postpartum amino acid concentrations and for concentrations on the fifth day of age, being established by discriminant analysis. These can be used to identify alterations inflicted upon amino acid metabolism by diabetes mellitus.
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PMID:[Amino acid imbalance in the blood of pregnant diabetic women and their newborn infants--limit values for screening. II. Neonatal amino acid imbalance]. 718 Feb 43

In non-insulin-dependent diabetes, site-specific defects of glucose metabolism in the pancreatic B-cell may account for a preferential alteration of its secretory response to the hexose. A novel therapeutic approach could thus be based on the use of non-glucidic nutrients that would bypass the metabolic defect in the islets of diabetic subjects. In this respect, the esters of mitochondrial dicarboxylic acids, such as succinic or glutamic acid, offer the advantage of being well transported into the islet cells and, hence, of stimulating efficiently both proinsulin biosynthesis and insulin release.
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PMID:[Current therapeutic approach to diabetes using esters of dicarboxylic mitochondrial metabolites]. 755 36

1. In non-insulin-dependent diabetes mellitus, the pancreatic B-cell displays a preferential impairment of its secretory response to D-glucose. 2. A number of agents could be used to restore secretory activity in the diseased B-cell. 3. In this respect, esters of carboxylic nutrients, such as succinic or glutamic acid, present the advantages of stimulating both proinsulin biosynthesis and insulin release, remaining efficient in models of B-cell glucotoxicity, augmenting the secretory response to hypoglycemic pharmacological agents, protecting the B-cell against cytotoxic aggressions, and exerting a long-term beneficial effect upon the secretory potential of the endocrine pancreas. 4. Potential limitations of this new therapeutical approach, such as the generation of methanol from the esters, their postulated inefficacy after enteral administration, or the occurrence of extrapancreatic metabolic effects may be circumvented. 5. The esters of carboxylic nutrients could even be used in other cells endangered by ATP depletion.
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PMID:The esters of carboxylic nutrients as insulinotropic tools in non-insulin-dependent diabetes mellitus. 759 Jan 1

The Brockmann body of the teleost fish, the tilapia (Oreochromis nilotica) has been considered as a potential source of islet xenograft tissue for patients with insulin-dependent diabetes. This study describes the purification from an extract of tilapia Brockmann bodies of insulin and several peptides arising from different pathways of post-translational processing of two proglucagons, two prosomatostatins and proPYY. The primary structure of tilapia insulin is similar to insulins from other teleosts (particularly the anglerfish, Lophius americanus) except that the strongly conserved glutamine residue at position 5 in the A-chain, a residue that is important in the binding of insulin to its receptor, is replaced by glutamic acid. In common with other teleosts, the tilapia Brockmann body expresses two non-allelic glucagon genes. Alternative pathways of post-translational processing lead to glucagons with 29 and 36 amino acid residues derived from proglucagon I and glucagons with 29 and 32 residues derived from proglucagon II. Glucagon-like peptides with 30 and 34 residues derived from proglucagon II were also isolated. In each case, the longer peptide is a C-terminally extended form of the shorter. Tilapia peptide tyrosine-tyrosine (PYY) was isolated in a C-terminally alpha-amidated from with 36 amino acid residues that is structurally similar (89% sequence identity) to anglerfish PYY. A 30-amino acid peptide, representing the C-terminal flanking peptide of PYY, was also isolated that shows only 53% sequence identity with the corresponding anglerfish peptide. Tilapia somatostatin-14 is identical to mammalian somatostatin but the [Tyr7, Gly10] somatostatin-containing peptide derived from prosomatostatin II contains the additional substitution (Phe11-->Leu) compared with the corresponding peptide from other teleosts.
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PMID:Characterization of the pancreatic hormones from the Brockmann body of the tilapia: implications for islet xenograft studies. 765 83

We report the clinical, biochemical, and molecular genetic findings in a family with an unusual mitochondrial disease phenotype harboring a novel mtDNA tRNA glutamic acid mutation at position 14709. The proband and his sister presented with congenital myopathy and mental retardation and subsequently developed cerebellar ataxia. Other family members had either adult-onset diabetes mellitus with muscle weakness or adult-onset diabetes mellitus alone. Ragged-red and cytochrome c oxidase (COX)-negative fibers were present in muscle biopsies. Biochemical studies of muscle mitochondria showed reduced complex I and IV activities. The mtDNA mutation was heteroplasmic in blood and muscle in all matrilineal relatives analyzed. Primary myoblast, but not fibroblast, cultures containing high proportions of mutant mtDNA exhibited impaired mitochondrial translation. These observations indicate that mtDNA tRNA point mutations should be considered in the differential diagnosis of congenital myopathy. In addition they illustrate the diversity of phenotypes associated with this mutation in the same family and further highlight the association between mtDNA mutations and diabetes mellitus.
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PMID:Congenital encephalomyopathy and adult-onset myopathy and diabetes mellitus: different phenotypic associations of a new heteroplasmic mtDNA tRNA glutamic acid mutation. 772 55

The dimethyl ester of L-glutamic acid (GME) stimulates insulin release in isolated pancreatic islets and may represent a novel experimental tool in the study of non-insulin-dependent diabetes. In the present study, GME was found both to stimulate insulin secretion and to augment glibenclamide-stimulated insulin release in normal anaesthetized rats. A comparable hierarchy in the magnitude of the secretory response to GME and/or glibenclamide was found in control rats and animals injected with streptozotocin during the neonatal period. In the latter animals, however, the B-cell secretory response was invariably lower than in control animals. It is proposed that GME represents a novel tool to bypass anomalies of glucose transport and metabolism in the beta cell and, hence, to stimulate insulin release and enhance the insulinotropic action of hypoglycaemic sulphonylurea in animal models of non-insulin-dependent diabetes.
Diabetes Res Clin Pract 1995 Jan
PMID:Stimulation of insulin secretion and potentiation of glibenclamide-induced insulin release by the dimethyl ester of glutamic acid in anaesthetized rats. 778 91

In an attempt to define the pathogenesis of congenital malformations in diabetic pregnancy, a number of serum factors were determined in normal and diabetic pregnant rats and correlated to the outcome of gestation with the aid of multivariate linear regression analysis. The animals were from two different lines of Sprague-Dawley rats with documented differences in rates of fetal dysmorphogenesis in diabetic pregnancy. The diabetic rats increased less in body weight than the normal rats, yet displayed increased liver and kidney weights. The serum concentrations of glucose, beta-hydroxybutyrate, triglycerides, the branched-chain amino acids, and asparagine, proline, alanine, citrulline, tyrosine, and ornithine were increased by diabetes. In contrast, IGF-I, glutamic acid, glutamine, cystine, and lysine were decreased in the serum of the diabetic pregnant rats. The maternal metabolic imbalance exerted profound effects on embryonic development. Thus, the embryos of the diabetic rats were smaller, had fewer somites, and contained less DNA and protein than the control embryos. In addition, the resorption and malformation rates were increased in the embryos of the diabetic rats. The regression analysis of the data revealed significant interrelationships between adverse embryonic outcome (rates of malformations and resorptions) and the maternal serum concentrations of glucose, triglycerides, beta-hydroxybutyrate, branched-chain amino acids, and creatinine. This suggests that the maternal metabolism of the three major classes of nutrients covariates with the embryonic development in diabetic rat pregnancy. The monitoring of only one of these maternal parameters, e.g. the serum glucose concentration, may therefore not adequately predict the developmental status of the offspring. Our results suggest that the pathogenesis of fetal malformations in diabetic pregnancy is multifactorial. Thus, maintaining metabolites from all nutrient classes at a normal level may be important in preventing adverse fetal outcome.
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PMID:Correlations between maternal metabolism and deranged development in the offspring of normal and diabetic rats. 778 44


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