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)

Serum Deoxyribonuclease (DNase) of normal persons and of patients with chronic pancreatitis, pancreatic cancer, Diabetes Mellitus, or other malignant diseases was determined with (32P) DNA as substrate. Serum DNase activity was much lower in patients with chronic pancreatitis, pancreatic cancer, or other malignant diseases than in control subjects, and serum DNase activity was almost normal in patients with Diabetes Mellitus. There was no correlation between serum DNase and serum amylase, but there was a good correlation between serum DNase and DNase I output in duodenal juice. There was an inverse correlation between serum DNase and serum RNase. These results imply that in the diagnosis of possible pancreatic disorders serum DNase may be a good indicator and thus may be useful for the detection of malignant diseases.
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PMID:Clinical investigation of serum deoxyribonuclease: II. Clinical studies of serum deoxyribonuclease activity in pancreatic disease. 52 Jul 66

The insulin-like growth factor I receptor (IGF-I-R) gene is expressed in most body tissues. The levels of IGF-I-R mRNA, however, are regulated by a number of physiological conditions (development, differentiation, and hormonal milieu) as well as in certain pathological states (diabetes and tumors). To understand the molecular mechanisms which control the transcription of the IGF-I-R gene, we have cloned the promoter of the rat receptor gene and have characterized its activity by transient expression assays. Different fragments of the 5'-flanking region (subcloned upstream of a luciferase reporter gene) were transfected into buffalo rat liver 3A cells (a cell line with a low number of IGF-I binding sites) and Chinese hamster ovary cells (a cell line with a higher number of cell-surface receptors). In both cell lines, most of the promoter activity was located in the proximal 416 base pairs of 5'-flanking region. However, further dissection of this proximal fragment revealed a cell type-specific pattern of promoter activity. Thus, in buffalo rat liver 3A cells, subfragments of this region each contributed to total activity, suggesting that contiguous cis-elements can act together to activate transcription. In Chinese hamster ovary cells, on the other hand, subfragments of the proximal promoter region partially substituted for the proximal 416 base pairs of 5'-flanking region. Coexpression studies using an IGF-I-R promoter reporter construct together with an Sp1 expression vector (under the control of an ADH promoter) were performed in SL2 cells, a Drosophila cell line which lacks endogenous Sp1. The results obtained showed that Sp1 can trans-activate the IGF-I-R promoter in vivo. Transient transfection assays were complemented with gel-retardation assays and DNase I footprinting experiments, which showed that transcription factor Sp1 is potentially an important regulator of IGF-I-R gene expression.
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PMID:Structural and functional analysis of the insulin-like growth factor I receptor gene promoter. 144 10

We identified the earliest events in autophosphorylation of the insulin receptor after insulin addition. Insulin-stimulated autophosphorylation at specific sites in the tyrosine kinase domain of the receptor's beta-subunit is correlated kinetically with activation of kinase-catalyzed phosphorylation of a model substrate (reduced and carboxyamidomethylated lysozyme; RCAM-lysozyme). To identify these sites, the deduced amino acid sequence of the 3T3-L1 adipocyte insulin receptor of the mouse was determined. Insulin-induced activation of substrate phosphorylation was shown to require autophosphorylation of three neighboring tyrosines (Tyr1148, Tyr1152, and Tyr1153) in the mouse receptor. A search for cellular substrates of the receptor kinase revealed that insulin causes accumulation of a 15,000-Mr phosphorylated (on tyrosine) cytosolic protein (pp15) in 3T3-L1 adipocytes treated with oxophenylarsine (PAO). PAO blocks turnover of the phosphoryl group of pp15, causing its accumulation, and thereby appears to interrupt signal transmission from the receptor to the glucose-transport system. Two membrane-bound protein phosphotyrosine phosphatases that are inhibited by PAO and are apparently responsible for the turnover of the pp15 phosphoryl group have been purified from 3T3-L1 adipocytes and characterized. These and other results support the hypothesis that turnover of the phosphoryl group of pp15, a product of insulin-receptor tyrosine kinase action, couples signal transmission to the glucose-transport system. [32P]pp15 was purified to homogeneity from 3T3-L1 adipocytes. Amino acid and radiochemical sequence analysis of the purified tryptic [32P]phosphopeptide revealed that pp15 is the phosphorylation product of 422(aP2) protein, a 15,000-Mr adipocyte protein whose cDNA we previously cloned and sequenced. 422(aP2) protein was found to bind fatty acids. When exposed to a free fatty acid, notably oleic acid, 422(aP2) protein becomes an excellent substrate of the isolated insulin-receptor tyrosine kinase. Compelling evidence indicates that on binding fatty acid, 422(aP2) protein undergoes a conformational change whereby Tyr19 becomes accessible to the receptor tyrosine kinase and undergoes O-phosphorylation. Adipose tissue and skeletal and heart muscle, which exhibit insulin-stimulated glucose uptake, express a specific insulin-responsive glucose transporter. A cDNA (GT2) that encodes this protein was isolated from a mouse 3T3-L1 adipocyte library and sequenced. We also isolated and characterized the corresponding mouse gene GLUT4. DNase I footprinting with nuclear extracts from 3T3-L1 cells revealed that a differentiation-specific nuclear factor binds to the GLUT4 promoter. The purified transcription factor C/EBP binds at the same position.(ABSTRACT TRUNCATED AT 400 WORDS)
Diabetes Care 1990 Jun
PMID:Insulin-receptor tyrosine kinase and glucose transport. 216 54

Insulin-like growth factor-I (IGF-I) gene transcription is mediated largely via exon 1. In an initial search for regulatory regions, rat hepatocytes were transfected with IGF-I constructs. Since omission of downstream sequences led to reduced expression, we then used in vitro transcription to evaluate potential metabolic regulation via downstream regions. With templates including 219 base pairs of downstream sequence, transcriptional activity was reduced 70-90% with hepatic nuclear extracts from diabetic versus normal rats. However, activity was comparable with templates lacking downstream sequences. The downstream region contained six DNase I footprints, and templates with deletion of either region III or V no longer provided reduced transcriptional activity with nuclear extracts from diabetic rats. Nuclear protein binding to regions III and V appeared to be metabolically regulated, as shown by reduced DNase I protection and activity in gel mobility shift assays with nuclear extracts from diabetic rats. Southwestern blotting probes corresponding to regions III and V recognized a approximately 65-kDa nuclear factor present at reduced levels in diabetic rats. These findings indicate that a downstream region in exon 1 may be important for both IGF-I expression and metabolic regulation. Altered concentration or activity of a transcription factor(s) binding to this region may contribute to reduced IGF-I gene transcription associated with diabetes mellitus.
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PMID:Transcriptional regulation of the rat insulin-like growth factor-I gene involves metabolism-dependent binding of nuclear proteins to a downstream region. 755 17

Glutamine:fructose-6-phosphate amidotransferase (GFAT) is the enzyme that is rate limiting in the synthesis of glucosamine and hexosamines. Glucosamine has been proposed to contribute to the glucotoxicity of diabetes. Evidence that the gene encoding GFAT is transcriptionally regulated prompted us to clone and characterize its promoter. The position of the mouse GFAT promoter relative to the translational start site was located by primer extension and found to be 149 bp upstream of the translational start site. A 1.9 kb SacI fragment of the GFAT gene was found to contain the promoter and 88 bp of sequence downstream of the transcriptional start site. This promoter segment could drive expression of a luciferase reporter gene, could confer correct transcriptional initiation to the reporter and could confer the EGF-responsiveness previously observed in the native gene. The mouse GFAT promoter lacks a canonical TATA box and has several GC boxes within a highly GC-rich region. Deletional analysis of the promoter indicated that a proximal element extending to -120 relative to the transcriptional start site could confer reporter expression at a level of 57% of the 1.9 kb construct. Detailed analysis of this proximal region by DNase I footprinting, electrophoretic mobility shift assays and site-directed mutagenesis indicated that Sp1 binds to three elements in this proximal promoter segment and plays a vital role in regulation of transcription from this gene.
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PMID:Cloning and partial characterization of the mouse glutamine:fructose-6-phosphate amidotransferase (GFAT) gene promoter. 906 Apr 44

In the liver, most insulin-like growth factor I (IGF-I) transcripts originate in exon 1, where important cis-regulatory regions are located downstream from the major transcription initiation sites. Within these regions, we have attempted to identify sequences which are involved in the decrease in IGF-I gene transcription associated with diabetes mellitus. The function of different genomic templates was assessed by in vitro transcription, which revealed a consistent 50-80% decrease in the activity of nuclear extracts from streptozotocin-diabetic as compared with normal rats. The disparity in transcriptional activity between normal and diabetic nuclear extracts was reduced with templates containing 11-bp mutations within DNase I protected regions III or V (+42 and +129 bp, respectively, from the major transcription initiation site), but a mutation between regions IV and V had little effect. Within region III, gel mobility shift analysis and methylation interference studies indicated that DNA-protein interactions involve a GCGC core sequence. In region V, gel mobility shift studies and uracil interference analysis revealed interactions involving a TTAT core. While gel mobility shift analysis and transient transfection studies indicate that the GCGC core sequence in region III recognizes C/EBP, the AT-rich sequence in region V is likely to recognize a protein with homeodomain characteristics. Identification of the nuclear factor(s) interacting with regions III and V, downstream from exon 1 initiation sites, will be important for understanding the mechanism of reduced IGF-I gene transcription due to diabetes mellitus.
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PMID:Identification of core sequences involved in metabolism-dependent nuclear protein binding to the rat insulin-like growth factor I gene. 1049 36

The increased expression of plasminogen activator inhibitor type-1 (PAI-1) is associated with increased concentrations of fatty acids in blood and may accelerate atherogenesis in diabetes. The present study was designed to define mechanisms by which nonesterified (free) fatty acids (FFAs) augment the expression of PAI-1. FFAs increased PAI-1 protein and mRNA expression by HepG2 cells. To identify potential regulatory elements, we constructed chimeric genes by fusing 1313, 853, 610, or 328 bp of human PAI-1 5'-flanking DNA to a luciferase reporter (PAI-LUC). A 2-fold increase in luciferase activity was seen when cells were transfected with PAI-LUC 1313, 863, or 610 and exposed to FFAs. No response to FFAs was seen with PAI-LUC 328 and after deletion of a 72-bp (-599 to -528) fragment from PAI-LUC 1313. This 72-bp fragment conferred FFA responsiveness to a different (simian virus 40) promoter. Two footprinted regions were demonstrated by DNase I analysis. Gel mobility shift assays indicated specific binding of extracted proteins to an FFA response element: 5'-TG(G/C)(1-2)CTG-3'. This sequence is repeated 4 times and is similar to an Sp1-binding site. Sp1 consensus oligonucleotides inhibited binding of extracted proteins to the regulatory elements. Accordingly, FFA-induced increased expression of PAI-1 in HepG2 cells is mediated by the binding of a transcription factor or factors to the repeated fatty acid response element, 5'-TG(G/C)(1-2)CTG-3', that is highly homologous to an Sp1-binding site.
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PMID:Identification and localization of a fatty acid response region in the human plasminogen activator inhibitor-1 gene. 1111 74

Recently, we have reported that biodegradable poly [alpha-(4-aminobutyl)-L-glycolic acid] (PAGA) can condense and protect plasmid DNA from DNase I. In this study, we investigated whether the systemic administration of pCAGGS mouse IL-10 (mIL-10) expression plasmid complexed with PAGA can reduce the development of insulitis in non-obese diabetic (NOD) mice. PAGA/mIL-10 plasmid complexes were stable for more than 60 min, but the naked DNA was destroyed within 10 min by DNase I. The PAGA/DNA complexes were injected into the tail vein of 3-week-old NOD mice. Serum mIL-10 level peaked at 5 days after injection, and could be detected for more than 9 weeks. The prevalence of severe insulitis on 12-week-old NOD mice was markedly reduced by the intravenous injection of PAGA/DNA complex (15.7%) compared with that of naked DNA injection (34.5%) and non-treated controls (90.9%). In conclusion, systemic administration of pCAGGS mIL-10 plasmid/PAGA complexes can reduce the severity of insulitis in NOD mice. This study shows that the PAGA/DNA complex has the potential for the prevention of autoimmune diabetes mellitus. Gene Therapy (2000) 7, 2099-2104.
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PMID:Degradable polymeric carrier for the delivery of IL-10 plasmid DNA to prevent autoimmune insulitis of NOD mice. 1122 91

For gene therapy, tissue targeting of gene delivery systems is required for the maximum efficiency. In this study, we constructed pRIP-IL4 in which the expression of interleukin-4 (IL-4) was driven by the rat insulin promoter. WSLP-pRIP-IL4 complex was characterized by pancreas beta-cell specific and glucose responsive expression of IL-4. pRIP-IL4 was completely retarded at a 6:1 or higher N/P (nitrogen atom of WSLP/phosphate of plasmid) ratio in 1% agarose gel. In addition, WSLP protected plasmid DNA from DNase I for more than 1 h. In cytotoxicity assay, WSLP showed less cytotoxicity than PEI (25000 Da) to mouse insulinoma (MIN6) cells. ELISA showed that pRIP-IL4 expressed much higher levels of IL-4 in MIN6 cells than in NIH3T3 cells. The expression level of IL-4 by pRIP-IL4 increased with increasing concentration of glucose. Also, IL-4 was expressed in a dose-dependent manner. This WSLP-pRIP-IL4 system will be useful in the development of a pancreas specific expression system for the prevention of diabetes without systemic side effects.
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PMID:Cell type specific and glucose responsive expression of interleukin-4 by using insulin promoter and water soluble lipopolymer. 1148 28

The regulation of the human Na(+)/I(-) symporter (NIS) gene is of considerable interest for both the diagnosis and therapy of thyroid pathologies. We investigated the influence of the thyroid-specific transcription factors TTF-1 and Pax8 on the NIS promoter and its 5'-flanking sequence. Reporter genes containing the corresponding genomic fragments coupled to a luciferase reporter gene were cotransfected with expression vectors carrying the the cDNA's for TTF-1 and Pax8. Transient transfection assays were performed in HeLa and COS-7 cells, which do not express endogenously these transcription factors. The experiments showed, that TTF-1 had no influence on the NIS promoter. Pax8, on the other hand, had a moderate stimulating effect (threefold) on the proximal NIS promoter. ABCD assays indicated an interaction of in vitro-translated Pax8 with the NIS promoter. However, DNase I footprinting experiments with bacterially expressed Pax8 were negative, suggesting an indirect mode of action with the participation of other proteins. A putative NIS upstream enhancer (NUE) 9000 bp upstream of the NIS gene, which was cloned based on its sequence homology to the rat NUE, was not transactivated by either Pax8 or TTF-1. The present data demonstrate, that the combination of Pax8 and TTF-1 is less important for NIS gene transcription than for other thyroid-specific genes. This is presumably related to the fact, that NIS is expressed also in other tissues such as mammary and salivary gland.
Exp Clin Endocrinol Diabetes 2001
PMID:Transcriptional regulation of the human sodium/iodide symporter gene by Pax8 and TTF-1. 1157 35


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