High glucose and endothelial cell growth: novel effects independent of autocrine TGF-beta 1 and hyperosmolarity.
Human endothelial cells were exposed to 5 mM glucose (control), 25 mM (high) glucose, or osmotic control for 72 h. TGF-beta1 production, cell growth, death, and cell cycle progression, and the effects of TGF-beta1 and TGF-beta neutralization on these parameters were studied. High glucose and hyperosmolarity increased endothelial TGF-beta1 secretion (P < 0.0001) and bioactivity (P < 0.0001). However, high glucose had a greater effect on reducing endothelial cell number (P < 0.001) and increasing cellular protein content (P < 0.001) than the osmotic control. TGF-beta antibody only reversed the antiproliferative and hypertrophic effects of high glucose. High glucose altered cell cycle progression and cyclin-dependent kinase inhibitor expression independently of hyperosmolarity. High glucose increased endothelial cell apoptosis (P < 0.01), whereas hyperosmolarity induced endothelial cell necrosis (P < 0.001). TGF-beta antibody did not reverse the apoptotic effects observed with high glucose. Exogenous TGF-beta1 mimicked the increased S phase delay but not endoreduplication observed with high glucose. High glucose altered endothelial cell growth, apoptosis, and cell cycle progression. These growth effects occurred principally via a TGF-beta1 autocrine pathway. In contrast, apoptosis and endoreduplication occurred independently of this cytokine and hyperosmolarity.
McGinn
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Department of Medicine, Kolling Institute: Renal Research Group, St Leonards, NSW 2065, Australia.
Poronnik
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King
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Gallery
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Pollock
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D000906:Antibodies / Q000378:metabolism; D017209:Apoptosis / Q000502:physiology; D019898:Autocrine Communication; D002453:Cell Cycle / Q000502:physiology; D018797:Cell Cycle Proteins / Q000378:metabolism; D002455:Cell Division / Q000502:physiology; D002478:Cells, Cultured; D050759:Cyclin-Dependent Kinase Inhibitor p21; D050760:Cyclin-Dependent Kinase Inhibitor p27; D016213:Cyclins / Q000378:metabolism; D003920:Diabetes Mellitus / Q000378:metabolism; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D009336:Necrosis; D009994:Osmolar Concentration; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2; D016212:Transforming Growth Factor beta / Q000235:genetics / Q000378:metabolism*; D053773:Transforming Growth Factor beta1; D025521:Tumor Suppressor Proteins / Q000378:metabolism; D051028:bcl-2-Associated X Protein
D000906:Antibodies; C493956:CDKN1A protein, human; D018797:Cell Cycle Proteins; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D004791:Enzyme Inhibitors; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; C508960:TGFB1 protein, human; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D025521:Tumor Suppressor Proteins; D051028:bcl-2-Associated X Protein; D050760:Cyclin-Dependent Kinase Inhibitor p27; D007770:L-Lactate Dehydrogenase; D005947:Glucose