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)

Abnormalities in extracellular matrix degradation may play a pathogenetic role in diabetic nephropathy. Cultured renal mesangial cells are known to synthesize increased amounts of matrix proteins when incubated in high glucose media (e.g., 30 mmol/l). However, the effect of glucose loading on degradative enzymes is unknown. Primary cultures of rat mesangial cells were grown until confluent in the presence of fetal calf serum (FCS) and insulin (0.67 U/ml). Cells were then cultured for 7 days in plastic wells in either 10 or 30 mmol/l glucose media containing neither FCS nor insulin. Collagenase activity in media were determined by zymography and quantitative spectrofluorometry. Cathepsin B and D activities in cell extracts were measured by spectrofluorometry (using the fluorescent substrate Z-Arg-Arg-7-amido-4-methylcoumarin) and 125I-labeled hemoglobin digestion, respectively. Gelatin-degrading activity of live mesangial cells was also determined. mRNA levels for collagenase IV, cathepsin B, and cathepsin D were determined by Northern analysis. A major band of collagenase activity with a molecular size of 72 kDa was observed in all mesangial cell media. Exposure of cells to high glucose media resulted in significant reductions in collagenase and cathepsin B activities as well as impairment in gelatin-degrading activity. Collagenase IV and cathepsin B and D mRNA levels were also decreased by glucose loading. To exclude the possibility that glucose loading was injurious to cells, 3H-leucine uptake (as a measure of protein synthesis) and membrane alkaline phosphatase activity (as a biochemical marker of viability) were not affected by the high glucose condition.(ABSTRACT TRUNCATED AT 250 WORDS)
Diabetes 1995 Aug
PMID:Decreased degradative enzymes in mesangial cells cultured in high glucose media. 762 99

The expression of mRNA and distribution of alpha 1(IV), alpha 3(IV) chains of type IV collagen, matrix metalloproteinase 2 (MMP-2), and tissue inhibitor of metalloproteinase 1 (TIMP-1) were examined in kidneys from streptozotocin-diabetic rats, 2.5 months after administration of the drug, an early time point when specific diabetic glomerular changes were still minimal. Ten age-matched Sprague-Dawley rats were assigned to control and diabetic groups. Compared to the controls, the diabetic rats had a significantly lower body weight, higher kidney weight and serum glucose levels, but no significant changes of glomerular surface area and urine albumin were observed. Northern blot analysis, using whole kidney mRNA, revealed that diabetic rat kidneys expressed 113.5% more alpha 1(IV), 46.5% more alpha 3(IV), 54.8% less MMP-2 and 246% more TIMP-1 (in all instances: p < 0.05). These results were corroborated by in situ hybridization for RNA expression. A quantitative analysis of the data indicated the following changes in glomeruli: (1) 74.6% more alpha 1(IV), (2) 103.8% more alpha 3(IV), (3) 40.7% less MMP-2 and (4) 80.9% more TIMP-1. Similar changes were observed in tubular (proximal and distal) cells. We conclude that an increased synthesis and decreased degradation of renal extracellular matrix components occur early after induction of experimental diabetes, before the onset of typical structural changes in the kidneys, and represent changes of specific gene expression at the transcriptional level. All the cell types in the glomerulus as well as the proximal and distal tubules appear to be involved in this alteration of expression, and this is a novel finding.
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PMID:Altered kidney matrix gene expression in early stages of experimental diabetes. 939 52

A number of studies have shown elevated matrix metalloproteinase expression in chronic wound fluid compared to an acute wound; however, little has been done to characterize animal models in a similar manner and thus determine their usefulness. The diabetes mouse is an animal model of type II diabetes that shows impaired dermal wound healing and has been proposed as a model of human impaired wound healing. In this study we have determined the mRNA and protein expression profiles of matrix metalloproteinases 2, 3, and 9 during the first 10 d of dermal healing for the diabetes mouse and its normally healing littermate. Additionally, human wound fluid from diabetic chronic wounds and acute surgical wounds were studied to enable a comparison of the model to the human condition. We show that during the early stages of wound healing the diabetes mouse possesses significantly reduced protein levels of pro-matrix metalloproteinases 2 and 9 within the wound tissue and active matrix metalloproteinase 3 within the fluid. Pro-matrix metalloproteinase 3 levels are also significantly reduced in the diabetes mouse during the later stages of healing. These differences may be contributing to the impaired healing of the diabetes mouse; however, they differ from the human data presented here, which show elevated matrix metalloproteinase 2 and reduced matrix metalloproteinase 9 in human diabetic chronic wound fluid compared to acute wound fluid. Therefore, although clearly showing the importance of appropriate matrix metalloproteinase regulation for normal acute wound healing to occur, the diabetes mouse may not be an ideal model for study of matrix metalloproteinase involvement in human chronic wound healing.
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PMID:Differential expression of matrix metalloproteinases during impaired wound healing of the diabetes mouse. 1216 30

Glycation has been implicated in the endothelial dysfunction that contributes to both diabetes- and aging-associated vascular complications. The aim of the present study was to determine whether Amadori-glycated phosphatidylethanolamine (Amadori-PE), a lipid-linked glycation compound that is formed at an increased rate in hyperglycemic states, affected proliferation, migration and tube formation of cultured human umbilical vein endothelial cells (HUVEC). Amadori-PE at a low concentration of less than 5 microM significantly enhanced these three factors involved in angiogenesis. Furthermore, stimulation of HUVEC with Amadori-PE resulted in secretion of matrix metalloproteinase 2 (MMP-2), a pivotal enzyme in the initial step of angiogenesis. Our results demonstrated for the first time that Amadori-PE may be an important compound that promotes vascular disease as a result of its angiogenic activity on endothelial cells. We also demonstrated that MMP-2 is a primary mediator of Amadori-PE-driven angiogenesis.
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PMID:Amadori-glycated phosphatidylethanolamine induces angiogenic differentiations in cultured human umbilical vein endothelial cells. 1464 53

The pathologic hallmarks of diabetic nephropathy are excess mesangial extracellular matrix (ECM) and mesangial cell proliferation. We previously showed that mesangial cell phenotypic changes play an important role in the pathogenesis of diabetic nephropathy. We concluded that phenotypic changes were present in bone marrow (BM)-derived mesangial cell progenitors, as transplantation of BM from db/db mice, a model of type 2 diabetic nephropathy, transferred the db genotype and a nephropathy phenotype to naive B6 mice recipients. The recipients did not develop diabetes; however, they did develop albuminuria and glomerular lesions mirroring those in the donors (i.e., glomerular hypertrophy, increased ECM, and increased cell number with cell proliferation). We found that matrix metalloproteinase 2 (MMP-2) facilitated invasion of the mesangial cells into ECM and proliferation in vitro. Thus, increased MMP-2 activity in db/db mesangial cell progenitors may partially explain increased mesangial cell repopulation and proliferation in B6 recipients of db/db BM. In summary, BM-derived mesangial cell progenitors may play a crucial role in the development and progression of ECM accumulation and mesangial cell proliferation in this model of diabetic nephropathy in type 2 diabetes.
Diabetes 2004 Sep
PMID:Development of albuminuria and glomerular lesions in normoglycemic B6 recipients of db/db mice bone marrow: the role of mesangial cell progenitors. 1533 54

Intra-abdominal fat accumulation is related to several diseases, especially diabetes and heart disease. Molecular mechanisms associated with this independent risk factor are not well established. Through the serial analysis of gene expression (SAGE) strategy, we have studied the transcriptomic effects of castration and dihydrotestosterone (DHT) in retroperitoneal adipose tissue of C57BL6 male mice. Approximately 50,000 SAGE tags were isolated in intact and gonadectomized mice, as well as 3 and 24 h after DHT administration. Transcripts involved in energy metabolism, such as glyceraldehyde-3-phosphate dehydrogenase, malic enzyme supernatant, fatty acid synthase, lipoprotein lipase, hormone-sensitive lipase and monoglyceride lipase, were upregulated by DHT. Transcripts involved in adipogenesis, and cell cycle and cell shape organization, such as DDX5, C/EBPalpha, cyclin I, procollagen types I, III, IV, V and VI, SPARC and matrix metalloproteinase 2, were upregulated by DHT. Cell defense, division and signaling, protein expression and many novel transcripts were regulated by castration and DHT. The present results provide global genomic evidence for a stimulation of glycolysis, fatty acids and triacylglycerol production, lipolysis and cell shape reorganization, as well as cell proliferation and differentiation, by DHT. The novel transcripts regulated by DHT may contribute to identify new mechanisms involved in the action of sex hormones and their potential role in obesity.
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PMID:Effects of dihydrotestosterone on adipose tissue measured by serial analysis of gene expression. 1552 99

For diabetes mellitus, little research has been done on the tissue-based or cell-based drug screening model, which has advantages over traditional animal diabetic model in high specificity, high screening volume, low cost and simple manipulation. Considering that the maintenance of complete islet tissue structure is the prerequisite for islet cells to perform their functions normally, an in vitro islet-based drug screening model for diabetes mellitus was established and evaluated. Pancreatic islets were isolated from 3 weeks old mice of either sex by collagenase digestion and density gradient centrifugation as prescribed by Ramanadham S. The volume of 0.1% (W/V) collagenase IV, 0.1% (W/V) Hyaluroridase and 0.1% (W/V) DNase I were 4 times, 2 times and 1 times that of the islets to be digested. And a 2 hours' cold digestion at 4 degrees C was followed by a 10 minutes' warm digestion at 37 degrees C. Under the optimized digestion condition, the islet recovery could be increased by 10%. The isolated islets could survive 6 weeks in vitro and show stable insulin secretion in the first 10 days after inoculation. The obtained islets were cultured in RPMI-1640 medium at 37 degrees C with 5% CO2. Then a diabetic model was established by selecting streptozotocin (STZ) as the evocator and nitric oxide (NO) as the responding index. After 1 day's inoculation, islets culture was treated with STZ, whose concentration ranged from 0 to 5.0 mmol/L. NO was measured by a colorimetric assay at 540nm based on the Griess reaction for 10 min with 0.1 mL Griess reagent and 0.1 mL culture supernatants. Insulin secretion was assayed by RIA methods. Due to the islets-related inoculation variations, NO release and insulin content were both expressed as a percentage of the value recorded in basal experiment which was in the only presence of Krebs culture medium. It was testified that the amount of NO released from islet itself remained steady at 30-35 mmol/L regardless of the changes of STZ concentration from 0 to 5.0 mmol/L. However the NO content in the supernatants of islets culture had close relationship with STZ concentration. This indicated that in this STZ-induced islet diabetic model, NO mainly comes from STZ when it dissolves in water. On the other hand, when STZ changed from 0 to 5.0 mmol/L, the dose-dependent relationship between NO content and insulin secretion showed that the increase of NO came along with the decrease of insulin secretion, which is an important symbol of islet function. As a kind of oxidative free radical, NO is capable of impair islet cells. Thus, NO is a reliable responding index of the model. The optimal STZ concentration in the model is finally determined to be 5.0 mmol/L, under which condition the NO content and insulin secretion is 10.81 times and 0.43 times that in the medium before STZ is added. So if anything is effective in lowering the NO content in the culture, it could protect islets cells from the oxidative attacks of NO. Finally, as an application of the model, the scavenging effect of KOSCr on NO was studied. In a series of KOSCr with different chromium content, all had shown better NO scavenging effects than KOS itself, which could give us an enlightenment of the influence of chromium ion on oligosaccharide. And 1 g/mL KOSCr with 3.519% chromium content can significantly inhibit the NO formation. This has lain a theoretic basis for the research of KOSCr bioactivity and quality control. These results suggested that the STZ-induced diabetic islet model which is impaired by NO free radical can be used effectively, fast and conveniently when screening potential diabetes drugs.
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PMID:[Establishment and application of the model of islet impaired by NO free radical released from streptozotocin]. 1596 20

The aim of this article is to provide methods for the isolation and identification of pancreatic stem cells and cell source for research and therapy of diabetes. ICCs were isolated by collagenase IV digesting and then cultured; epithelial cells were purified from monolayer cultured ICCs. The growth curve of the epithelial cells was measured by MTT. The expression of molecular markers in the cells was identified by immunohistochemical staining. The surface markers in the epithelial cells were analyzed by FACS. Epithelial cells were purified from isolated human fetal ICCs and passaged 40 times, and 10(6) - 10(8) cells were cryopreservated per passage. The growth curve demonstrated that the epithelial cells proliferated rapidly. The epithelial cells expressed PDX-1, PCNA, CK-7, CK-19, Nestin, Glut2, and Vimentin, but Insulin was undetected. The cells expressed CD29, CD44, and CD166, but did not express CD11a, CD14, CD34, CD45, CD90, CD105, and CD117. Taken together, these results indicate that self-renewable epithelial cells can be isolated and purified from human fetal pancreas. These also show that the epithelial cells originate from ducts and have the characteristics of pancreatic stem cells.
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PMID:[Isolation, purification and identification of epithelial cells derived from fetal islet-like cell clusters]. 1746 Aug 96

Atrial fibrillation (AF) may result from an electric conduction disturbance, increased hemodynamic stress, ischemia, inflammation, or remodeling in atria. Although genetic epidemiological studies have identified several genetic variants as risk factors for AF, the genetic determinants of this condition remain largely unknown. The purpose of the present study was to identify gene polymorphisms that confer susceptibility to lone AF. The study population comprised 1069 unrelated Japanese individuals, including 196 subjects with chronic lone AF and 873 controls. The genotypes for 40 polymorphisms of 32 candidate genes were determined by a method that combines the polymerase chain reaction and sequence-specific oligonucleotide probes with suspension array technology. Multivariable logistic regression analysis with adjustment for age, sex, body mass index, and the prevalence of smoking, hypertension, diabetes mellitus, and hyperchole-sterolemia as well as a stepwise forward selection procedure revealed that the -1306C-->T polymorphism of the matrix metalloproteinase 2 gene (MMP2) and the -592A-->C polymorphism of the interleukin 10 gene (IL10) were significantly (false discovery rate of <0.05) associated with the prevalence of AF. The T allele of the MMP2 polymorphism and the C allele of the IL10 polymorphism were a risk factor for and protective factor against AF, respectively. Determination of the genotypes for these polymorphisms may thus prove informative for assessment of the genetic component of AF.
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PMID:Genetic factors for lone atrial fibrillation. 1748 26

Remodeling of extracellular matrix (ECM) is an important physiological feature of normal growth and development. Recent studies have emphasized the role of matrix metalloproteinases (MMP-2 and MMP-9) in normal mouse nephrogenesis. We have demonstrated previously in the rat that in utero exposure to maternal diabetes impairs renal development leading to a 30% reduction in the nephron number. Transforming growth factor-beta1 (TGF-beta1) and connective tissue growth factor (CTGF) are known to mediate high glucose effects on matrix degradation. The aim of the present study was to address the expression of type IV collagenase and TGF-beta1/CTGF systems in rat kidney during normal development and after in utero exposure to maternal diabetes. Both MMP-2 and MMP-9 mRNA metanephric expressions and activities were dramatically downregulated in kidneys issued from diabetic fetuses and in metanephros cultured in the presence of high glucose concentration. TGF-beta1 and CTGF expressions were significantly enhanced in diabetic fetal kidneys and in high glucose cultured metanephroi. Conditioned media obtained from metanephroi grown with high glucose concentration upregulated functional TGF-beta activity in transfected ATDC5 cells. In conclusion, in impaired nephrogenesis resulting from in utero exposure to maternal diabetes, alteration of both type IV collagenase and TGF-beta1/CTGF systems may lead to abnormal remodeling of ECM, which may, in turn, induce defects in ureteral bud branching leading to the observed reduction in the nephron number with consequences later in life: progression of chronic renal disease and hypertension.
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PMID:Expression of matrix metalloproteinases MMP-2 and MMP-9 is altered during nephrogenesis in fetuses from diabetic rats. 1749 4


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