Purpose: To examine for the expression of 15-lipoxygenase 1 (15-LOX1) and 15-LOX2 in human retinal microvascular endothelial cells (HRMVECs) and study the role of arachidonic acid metabolites of these enzymes in angiogenesis.
Methods: Quantitative RT-PCR and reverse-phase HPLC analyses were used to determine 15-LOX1/2 expression and their arachidonic acid metabolites in HRMVECs. The role of MEK1 in 15(S)-HETE-induced angiogenesis was studied using HRMVEC migration, tube formation, and basement membrane matrix plug angiogenesis.
Results: HRMVECs expressed both 15-LOX1 and 15-LOX2. Hypoxia induced the expression of 15-LOX1 and the production of its arachidonic acid metabolites 15(S)-hydroxyeicosatetraenoic acid (15(S)-HETE) and 12(S)-hydroxyeicosatetraenoic acid (12(S)-HETE). 15(S)-HETE stimulated HRMVEC migration and tube formation as potently as 20 ng/mL fibroblast growth factor-2 (FGF-2). In addition, 15(S)-HETE stimulated the phosphorylation of ERK1/2, JNK1, p38 MAPK, and MEK1 in a time-dependent manner in these cells. Inhibition of MEK1 by pharmacologic and dominant-negative mutant approaches attenuated 15(S)-HETE-induced phosphorylation of ERK1/2 and JNK1 but not p38 MAPK. Blockade of ERK1/2 and JNK1 activation suppressed 15(S)-HETE-induced HRMVEC migration and tube formation and basement membrane matrix plug angiogenesis. Inhibition of p38 MAPK attenuated 15(S)-HETE-induced HRMVEC migration only. Inhibition of MEK1 also blocked 15(S)-HETE-induced HRMVEC migration and tube formation and basement membrane matrix plug angiogenesis.
Conclusions: These results suggest that hypoxia, through the induction of 15-LOX1 expression, leads to the production of 15(S)-HETE in HRMVECs. In addition, 15(S)-HETE, through MEK1-dependent activation of ERK1/2 and JNK1, stimulates the angiogenic differentiation of HRMVECs and basement membrane matrix plug angiogenesis.
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http://dx.doi.org/10.1167/iovs.07-0617 | DOI Listing |
Exp Mol Med
August 2024
Integrative Biosciences Center, Wayne State University, Detroit, MI, 48202, USA.
Human interleukin-33 (IL-33) is a 270 amino acid protein that belongs to the IL-1 cytokine family and plays an important role in various inflammatory disorders. Neutrophil proteases (Cathepsin G and Elastase) and mast cell proteases (tryptase and chymase) regulate the activity of IL-33 by processing full-length IL-33 into its mature form. There is little evidence on the role of these mature forms of IL-33 in retinal endothelial cell signaling and pathological retinal angiogenesis.
View Article and Find Full Text PDFCell Death Dis
May 2020
Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA.
Pathological retinal neovascularization is the most common cause of vision loss. PKCθ has been shown to play a role in type 2 diabetes, which is linked to retinal neovascularization. Based on these clues, we have studied the role of PKCθ and its downstream target genes JunB and VEGFR3 in retinal neovascularization using global and tissue-specific knockout mouse models along with molecular biological approaches.
View Article and Find Full Text PDFExp Eye Res
April 2019
Department of Ophthalmology, University Medical Center Greifswald, Germany. Electronic address:
Background: Human retinal microvascular endothelial cells (HRMVECs) are involved in the pathogenesis of retinopathy of prematurity. In this study, the microRNA (miRNA) expression profiles of HRMVECs were investigated under resting conditions, angiogenic stimulation (VEGF treatment) and anti-VEGF treatment.
Materials And Methods: The miRNA profiles of HRMVECs under resting and angiogenic conditions (VEGF treatment), as well as after addition of aflibercept, bevacizumab or ranibizumab were evaluated by analyzing the transcriptome of small non-coding RNAs.
Biosci Trends
January 2017
Department of Diabetic Complications, Diabetes Research Center, Research Institute, National Center for Global Health and Medicine.
Retinal pericytes play an important role in the maintenance of retinal microvascular homeostasis. We performed a secretory peptidome of primary human retinal pericytes. Using liquid chromatography-tandem mass spectrometry analysis in the culture medium of retinal pericytes, we identified 256 peptides derived from 114 proteins, and identified a novel partial fragment Leu163-His183 (termed ΔADT) of adrenotensin (ADT).
View Article and Find Full Text PDFSci Rep
May 2016
Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA.
Despite the involvement of proline-rich tyrosine kinase 2 (Pyk2) in endothelial cell angiogenic responses, its role in pathological retinal angiogenesis is not known. In the present study, we show that vascular endothelial growth factor A (VEGFA) induces Pyk2 activation in mediating human retinal microvascular endothelial cell (HRMVEC) migration, sprouting and tube formation. Downstream to Pyk2, VEGFA induced signal transducer and activator of transcription 3 (STAT3) activation and cJun expression in the modulation of HRMVEC migration, sprouting and tube formation.
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