title: Identification of microRNA-93 as a novel regulator of vascular endothelial growth factor in hyperglycemic conditions.
abstract: Vascular endothelial growth factor (VEGF) is a dimeric glycoprotein that plays a crucial role in microvascular complications of diabetes, including diabetic nephropathy. However, the precise regulatory mechanisms governing VEGF expression in the diabetic milieu are still poorly understood. Here, we provide evidence that microRNA-93 (miR-93) regulates VEGF expression in experimental models of diabetes both in vitro and in vivo. Comparative microRNA expression profile arrays identified miR-93 as a signature microRNA in hyperglycemic conditions. We identified VEGF-A as a putative target of miR-93 in the kidney with a perfect complementarity between miR-93 and the 3'-untranslated region of vegfa in several species. When cotransfected with a luciferase reporter construct containing the mouse vegfa 3'-untranslated region, expression of miR-93 markedly decreased the luciferase activity. We showed that forced expression of miR-93 in cells abrogated VEGF protein secretion. Conversely, anti-miR-93 inhibitors increased VEGF release. Transfection of miR-93 also prevented the effect of high glucose on VEGF downstream targets. Using transgenic mice containing VEGF-LacZ bicistronic transcripts, we found that inhibition of glomerular miR-93 by peptide-conjugated morpholino oligomers elicited increased expression of VEGF. Our findings also indicate that high glucose decreases miR-93 expression by down-regulating the promoter of the host MCM7 gene. Taken together, our findings provide new insights into the role of miR-93 in VEGF signaling pathway and offer a potentially novel target in preventing the progression of diabetic nephropathy.
authors.affiliation: Division of Nephrology, Department of Medicine, Baylor College of Medicine, Houston, Texas 77030, USA.
authors.forename: Jianyin
authors.initials: J
authors.lastname: Long
authors.forename: Yin
authors.initials: Y
authors.lastname: Wang
authors.forename: Wenjian
authors.initials: W
authors.lastname: Wang
authors.forename: Benny H J
authors.initials: BH
authors.lastname: Chang
authors.forename: Farhad R
authors.initials: FR
authors.lastname: Danesh
mesh_terms: D020413:3' Untranslated Regions / Q000235:genetics; D000818:Animals; D001483:Base Sequence; D018797:Cell Cycle Proteins / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics; D003920:Diabetes Mellitus / Q000235:genetics / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation / Q000187:drug effects; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism; D005947:Glucose / Q000494:pharmacology; D006367:HeLa Cells; D006801:Humans; D006943:Hyperglycemia / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D051379:Mice; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism*; D055806:Microvessels / Q000166:cytology; D064168:Minichromosome Maintenance Complex Component 7; D008969:Molecular Sequence Data; D009025:Morpholines / Q000737:chemistry / Q000494:pharmacology; D009687:Nuclear Proteins / Q000235:genetics; D050199:Podocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D011108:Polymers / Q000737:chemistry; D011401:Promoter Regions, Genetic / Q000235:genetics; D015203:Reproducibility of Results; D014158:Transcription, Genetic; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics* / Q000378:metabolism
chemical_list: D020413:3' Untranslated Regions; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D035683:MicroRNAs; C551470:Mirn93 microRNA, mouse; D009025:Morpholines; D009687:Nuclear Proteins; D011108:Polymers; D042461:Vascular Endothelial Growth Factor A; C467480:vascular endothelial growth factor A, mouse; C037574:morpholine; C491086:Mcm7 protein, mouse; D064168:Minichromosome Maintenance Complex Component 7; D005947:Glucose