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)

Both blood vessels and nerves are guided to their tissue targets by "specific" growth factors such as vascular endothelial growth factor (VEGF) and nerve growth factor (NGF), originally discovered as growth factors specific for endothelial and neuronal cells, respectively. While the eminent role of VEGF in the formation of new blood vessels (angiogenesis) is unquestioned, recent studies indicate that VEGF also has direct effects on the nervous system in terms of neuronal growth, survival (neurotrophic), axonal outgrowth (neurotropic), and neuroprotection. Conversely, NGF, a neurotrophin that plays a crucial role in promoting neurotrophic and neurotropic effects in sympathetic neurons, has recently been identified as a novel angiogenic molecule exerting a variety of effects on endothelial cells and in the cardiovascular system in general. VEGF and NGF have also been implicated in both neurodegenerative and vascular diseases. The pleiotropic effects of these growth factors have raised interest in assessing their therapeutic potential. The challenge for the future is to unravel to what extent the effects of these growth factors are interrelated with regards to their angiogenic, and neurotrophic effects and how to design selective drugs interfering with their respective actions. Most biological actions of NGF and VEGF are mediated by their cognate receptor protein tyrosine kinases, tropomyosin related kinase (trkA for NGF) and kinase insert domain-containing receptor (KDR, VEGFR-2, flk-1 for VEGF), which activate a complex and integrated network of signaling pathways in neurons and endothelial cells. Two small molecules, K252a and SU-5416, which are antagonists of trkA and VEGFR-2, respectively, may serve as key tools in dissecting the role of NGF and VEGF in angiogenesis and neurogenesis. Development of selective drugs specific for the trkA and VEGFR-2 subtypes of receptors will provide new tools for the treatment of neurodegenerative diseases, such as Alzheimer's and Parkinson's, as well as of numerous angiogenesis-dependent diseases, such as cancer, diabetes, and arthritis.
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PMID:Cross talk between the cardiovascular and nervous systems: neurotrophic effects of vascular endothelial growth factor (VEGF) and angiogenic effects of nerve growth factor (NGF)-implications in drug development. 1684 61

Plaque angiogenesis may be associated with the development of unstable and vulnerable plaques. Vascular endothelial growth factors (VEGFs) are potent angiogenic factors that can affect plaque neovascularization. Our objective was to determine the effect of diabetes on atherosclerosis and on the expression of angiogenesis-related genes in atherosclerotic lesions. Alloxan was used to induce diabetes in male Watanabe heritable hyperlipidemic (WHHL) rabbits that were sacrificed 2 and 6 months after the induction of diabetes. Nondiabetic WHHL rabbits served as controls. Blood glucose (Glc), serum-free fatty acids (FFA), and serum triglyceride levels were significantly higher in diabetic rabbits. Accelerated atherogenesis was observed in the diabetic WHHL rabbits together with increased intramyocellular lipids (IMCL), as determined by 1H-NMR spectroscopy. Atherosclerotic lesions in the diabetic rabbits had an increased content of macrophages and showed significant increases in immunostainings for vascular endothelial growth factor (VEGF)-A, VEGF-D, VEGF receptor-1, VEGF receptor-2, RAGE, and NF-kappaB. VEGF-A165 and VEGFR-2 mRNA levels were significantly increased in aortas of the diabetic rabbits, where a trend toward increased plaque vascularization was also observed. These results suggest that diabetes accelerates atherogenesis, up-regulates VEGF-A, VEGF-D, and VEGF receptor-2 expression, and increases NF-kappaB, RAGE, and inflammatory responses in atherosclerotic lesions in WHHL rabbits.
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PMID:VEGF-A, VEGF-D, VEGF receptor-1, VEGF receptor-2, NF-kappaB, and RAGE in atherosclerotic lesions of diabetic Watanabe heritable hyperlipidemic rabbits. 1693 42

Vascular endothelial growth factor (VEGF) is a potent stimulating factor for angiogenesis and vascular permeability. There are eight isoforms with different and sometimes overlapping functions. The mechanisms of action are under investigation with emerging insights into overlapping pathways and cross-talk between other receptors such as the neuropilins, which were not previously associated to angiogenesis. VEGF has important physiological actions on embryonic development, healing, and menstrual cycle. It also has a great role in pathological conditions that are associated to autoimmune diseases. There is considerable evidence in various autoimmune diseases such as in systemic lupus erythematosus, rheumatoid arthritis, and multiple sclerosis of an interrelationship between the VEGF system and theses disorders. Serum levels of VEGF correlate with disease activity in a large number of autoimmune diseases and fall with the use of standard therapy. We raised the possible future therapeutic strategies in autoimmune diseases with the anti-VEGF or anti-VEGFR (receptor). So far, this therapy has been used in cancer and macular ocular degeneration in diabetes. This review outlines the evidence for VEGF participation in various autoimmune diseases and proposes lines for future research in this field.
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PMID:Vascular endothelial growth factor (VEGF) in autoimmune diseases. 1734 Jan 92

Deficient angiogenesis after ischemia may contribute to worse outcomes of peripheral arterial disease in patients with diabetes mellitus (DM). Vascular endothelial growth factor (VEGF) and its receptors promote angiogenesis. We hypothesized that in peripheral arterial disease, maladaptive changes in VEGF ligand/receptor expression could account for impaired angiogenesis in DM. Skeletal muscle from diet-induced, type 2 diabetic (DM) and age-matched normal chow (NC)-fed mice was collected at baseline and 3 and 10 days after hindlimb ischemia and analyzed for expression of VEGF (n=10 per group), full-length VEGF receptor (VEGFR)-1, soluble VEGFR-1, and markers of downstream VEGF signaling (n=20 per group) using ELISA, reverse transcriptase-polymerase chain reaction, and Western blots. In the absence of ischemia, DM mice had increased VEGF (NC versus DM: 26.6+/-2.6 versus 53.5+/-8.8 pg/mg protein; P<0.05), decreased soluble and membrane-bound VEGFR-1 (NC versus DM: 1.44+/-0.30 versus 0.85+/-0.08 and 1.03+/-0.10 versus 0.72+/-0.10, respectively; P<0.05), decreased phospho-AKT/AKT and phospho-endothelial NO synthase/endothelial NO synthase (NC versus DM: 0.76+/-0.2 versus 0.38+/-0.1 and 0.36+/-0.06 versus 0.25+/-0.04, respectively; P<0.05), and no change in VEGFR-2. After ischemia, both DM and NC had comparable increases in VEGF-A. VEGFR-1 and soluble VEGFR-1 expression increased in both groups, but the fold increase was significantly greater in DM. These data demonstrate that soluble VEGFR-1, an angiogenesis inhibitor, is regulated in skeletal muscle by type 2 DM and ischemia. In the absence of ischemia, despite reductions in both soluble VEGFR-1 and VEGFR-1, VEGF ligand signaling is lower in DM compared with controls. After ischemia, maladaptive upregulation of these receptors further reduces the capacity of VEGF to induce an angiogenic response, which may provide a novel target for therapy.
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PMID:Impaired angiogenesis after hindlimb ischemia in type 2 diabetes mellitus: differential regulation of vascular endothelial growth factor receptor 1 and soluble vascular endothelial growth factor receptor 1. 1782 71

Ang-1 (angiopoietin-1) improves the ineffective angiogenesis and impaired wound healing in diabetes; however, the mechanism underlying this positive effect is still far from being completely understood. In the present study, we investigated whether rAAV (recombinant adeno-associated virus)-Ang-1 gene transfer could improve wound repair in genetically diabetic mice (db+/db+) and the mechanism(s) by which it causes new vessel formation. An incisional skin-wound model in diabetic and normoglycaemic mice was used. After the incision, animals received rAAV-LacZ or rAAV-Ang-1 in the wound edge. After 7 and 14 days, wounds were used to (i) confirm Ang-1 gene transfer, (ii) assess histologically the healing process, (iii) evaluate wound-breaking strength, and (iv) study new vessel formation by PECAM-1 (platelet/endothelial cell adhesion molecule-1) immunostaining. Finally, we investigated VEGF (vascular endothelial growth factor) mRNA and protein levels, eNOS (endothelial NO synthase) expression and VEGFR-1 and VEGFR-2 (VEGF receptor-1 and -2 respectively) immunostaining. The efficiency of Ang-1 gene transfer was confirmed by increased mRNA and protein expression of the protein. rAAV-Ang-1 significantly improved the healing process, stimulating re-epithelization and collagen maturation, increasing breaking strength and significantly augmenting the number of new vessels, as indicated by PECAM-1 immunostaining. However, Ang-1 gene transfer did not modify the decrease in VEGF mRNA and protein expression in diabetic mice; in contrast, Ang-1 increased eNOS expression and augmented nitrate wound content and VEGFR-2 immunostaining and protein expression. Ang-1 gene transfer did not change vascular permeability. Similar results were obtained in normoglycaemic animals. In conclusion, our results provide strong evidence that Ang-1 gene transfer improves the delayed wound repair in diabetes by inducing angiogenesis in a VEGF-independent manner.
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PMID:Angiopoietin-1 gene transfer improves impaired wound healing in genetically diabetic mice without increasing VEGF expression. 1807 86

Retinal and choroidal vascular diseases, with their associated abnormalities in vascular permeability, account for the majority of patients with vision loss in industrialized nations. VEGF is upregulated in ischemic retinopathies such as diabetes and is known to dramatically alter vascular permeability in a number of nonocular tissues via Src kinase-regulated signaling pathways. VEGF antagonists are currently in clinical use for treating the new blood vessels and retinal edema associated with neovascular eye diseases, but such therapies require repeated intraocular injections. We have found that vascular leakage following intravitreal administration of VEGF in mice was abolished by systemic or topical delivery of what we believe is a novel VEGFR2/Src kinase inhibitor; this was confirmed in rabbits. The relevance of Src inhibition to VEGF-associated alterations in vascular permeability was further substantiated by genetic studies in which VEGF injection or laser-induced vascular permeability failed to augment retinal vascular permeability in Src-/- and Yes-/- mice (Src and Yes are ubiquitously expressed Src kinase family members; Src-/- and Yes-/- mice lacking expression of these kinases show no vascular leak in response to VEGF). These findings establish a role for Src kinase in VEGF-mediated retinal vascular permeability and establish a potentially safe and painless topically applied therapeutic option for treating vision loss due to neovascular-associated retinal edema.
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PMID:Retinal vascular permeability suppression by topical application of a novel VEGFR2/Src kinase inhibitor in mice and rabbits. 1848 22

The study included 20 patients with diabetes mellitus type I (DM I) and 16 with type II (DM II) suffering from prolipherative diabetic retinopathy (PDR) for which they underwent vitrectomy. The quantity of VEGF and its receptors in the vitreous of investigated patients were measured by immunoassay and results compared between patients with DM I and II. The mean levels in the vitreous were significantly higher in diabetics with PDR and diabetes mellitus I (432.2 pg/mL, 1460.4 pg/mL and 1054.6 pg/mL) than in diabetics with PDR and diabetes mellitus II (147.5 pg/mL, 641.4 pg/mL and 448.5 pg/mL) and in control group (63.26 pg/mL). Considering that VEGF VEGFR1 and VEGFR2 levels were significantly higher in diabetics with PDR than in controls and that the patients with DM I had higher levels than with DM II, anti-VEGF therapy might be beneficial for diabetics with PDR, especially those with DM I.
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PMID:Expression of vascular endothelial growth factor in proliferative diabetic retinopathy. 1913 4

Peripheral artery disease is characterized by reduced blood flow to the lower limb, resulting in chronic ischemia in these muscles, which can lead to eventual amputation of the affected limb. Stimulation of angiogenesis in the ischemic region would be of therapeutic benefit; however, attempts to increase angiogenesis through delivery of vascular endothelial growth factor (VEGF) largely have been unsuccessful. Recent studies have shown that VEGF signaling through its receptors, VEGFR1 and VEGFR2, is much more complex than previously appreciated. This review will examine current research into the function of VEGFR1 and -2 signaling pathways, and evidence of cross-talk between these two receptors. The potential impact of endothelial cell co-stimulation via other growth factors/cell surface receptors (such as angiopoietins and ephrins) on angiogenesis also will be discussed. Evidence suggesting deficiencies in VEGF pathway signaling in individuals with chronic ischemia and diabetes will be discussed. Numerous pro-angiogenic therapies for ischemia have been employed. The successes and limitations of these therapies will be illustrated, emphasizing more recent angiogenesis therapies that focus on activating co-ordinated patterns of pro-angiogenic genes as the most promising direction in the treatment of ischemic muscle tissue in peripheral artery disease.
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PMID:Evolving strategies in manipulating VEGF/VEGFR signaling for the promotion of angiogenesis in ischemic muscle. 1919 67

Epithelial ovarian cancer (EOC) is a serious gynecological cancer and there may be an increased risk of developing EOC in women with metabolic disruptions such as diabetes-related hyperglycemia, obesity or high glycemic load. Upregulation of vascular endothelial growth factor (VEGF) in ischemic conditions (e.g. hypoxia, hypoglycemia) induces tumor angiogenesis. We previously showed that EOC cells employ an autocrine VEGF/VEGFR2 signaling loop. Here we demonstrate the influence of glucose levels on VEGF and its receptors in the human EOC lines OVCAR-3 and CAOV-3. Glucose (but not pyruvate) deprivation induced significant increase in VEGF transcription and secretion, but a rapid reduction in VEGFR2 protein synthesis and glycosylation, combined with a reduction in co-receptor neuropilin-1 (NRP-1) protein levels. In contrast, mRNA for KDR and NRP-1 was increased upon glucose depletion suggesting a mechanism of feed back upon protein reduction. The addition of the proteosome inhibitor epoxomycin restored VEGFR2 under glucose free conditions, suggesting degradation as the main mechanism of VEGFR2 reduction and transcriptional activation through the unfolded protein response (UPR) which was activated in glucose-starved cells through the upregulation of the Endoplasmic reticulum chaperon GRP-78. Our finding that glucose can regulate VEGF/VEGFR2 levels suggests that initiation and/or progression of ovarian surface epithelial cells towards a neoplastic phenotype might be modulated by dietary conditions, and that a patient's metabolic status may alter the effectiveness of the known anti-angiogenic therapies. This information provides opportunities to explore the biology of EOC progression and improve our understanding of the mechanistic insight of this interesting regulatory effect.
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PMID:Glucose is a key regulator of VEGFR2/KDR in human epithelial ovarian carcinoma cells. 1978 46

Previous work identified an important role for hyperglycemia in diabetic nephropathy (The Diabetes Control and Complications Trial Research Group. N Engl J Med 329: 977-986, 1993; UK Prospective Diabetes Study Group. Lancet 352: 837-853, 1998), and increased glomerular GLUT1 has been implicated. However, the roles of GLUT1 and intracellular glucose have not been determined. Here, we developed transgenic GLUT1-overexpressing mice (GT1S) to characterize the roles of GLUT1 and intracellular glucose in the development of glomerular disease without diabetes. GLUT1 was overexpressed in glomerular mesangial cells (MC) of C57BL6 mice, a line relatively resistant to diabetic nephropathy. Blood pressure, blood glucose, glomerular morphometry, matrix proteins, cell signaling, transcription factors, and selected growth factors were examined. Kidneys of GT1S mice overexpressed GLUT1 in glomerular MCs and small vessels, rather than renal tubules. GT1S mice were neither diabetic nor hypertensive. Glomerular GLUT1, glucose uptake, mean capillary diameter, and mean glomerular volume were all increased in the GT1S mice. Moderately severe glomerulosclerosis (GS) was established by 26 wk of age in GT1S mice, with increased glomerular type IV collagen and fibronectin. Modest increases in glomerular basement membrane thickness and albuminuria were detected with podocyte foot processes largely preserved, in the absence of podocyte GLUT1 overexpression. Activation of glomerular PKC, along with increased transforming growth factor-beta1, VEGFR1, VEGFR2, and VEGF were all detected in glomeruli of GT1S mice, likely contributing to GS. The transcription factor NF-kappaB was also activated. Overexpression of glomerular GLUT1, mimicking the diabetic GLUT1 response, produced numerous features typical of diabetic glomerular disease, without diabetes or hypertension. This suggested GLUT1 may play an important role in the development of diabetic GS.
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PMID:Transgenic overexpression of GLUT1 in mouse glomeruli produces renal disease resembling diabetic glomerulosclerosis. 2037 17


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