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Journal Article 2008; 29(5): 775-778 PubMed PMID: 18987578 Citation  Keywords:  Aldehyde Reductase:antagonists & inhibitors, Animals, Blotting, Western, Calcimycin:pharmacology, Cattle, Cell Line, Electrochemistry, Endothelial Cells:drug effects, Endothelium, Vascular:drug effects, Enzyme Inhibitors:pharmacology, Glucose:pharmacology.   

OBJECTIVES: An increased glucose utilization by aldose reductase (ALR-2) has been implicated in the pathogenesis of diabetic vascular complications. In this process, several mechanisms are involved, including the depletion of cofactors required for the action of antioxidant enzymes or endothelial NO synthase. In this study, the effect of a novel ALR-2 inhibitor JMC-2004 on hyperglycemia-induced endothelial dysfunction was studied.

METHODS: Bovine aortic endothelial cells (BAEC) were treated with glucose (30 mM), JMC-2004 (0.01mM), or glucose and JMC-2004 for 24 h. The cells were then stimulated with calcium ionophore A23187 after which NO production was measured electrochemically using a porphyrine-coated carbon NO electrode. Nitrite concentrations were determined in the cell supernatants. The peroxyl and hydroxyl radical-scavenging activity of JMC-2004 was measured with luminol-enhanced chemiluminescence. The expression of eNOS was determined by Western blotting. JMC-2004 IC50 for ALR-2 was determined colorimetrically with D-glyceraldehyde as a substrate.

RESULTS: Incubating the cells with 30 mM glucose strongly diminished A23187- induced NO production. Treatment with JMC-2004 restored NO production by 40% without affecting eNOS expression. This effect was probably antioxidantindependent, since JMC-2004 did not have any antioxidant capacity. JMC-2004 exerted high selectivity towards ALR-2.

CONCLUSIONS: ALR-2 inhibition with JMC-2004 was able to abolish hyperglycemia- induced endothelial dysfunction in bovine aortic endothelial cells....

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Journal Article 2002; 23(2): 95-100 PubMed PMID: 12011792 Citation  Keywords:  Adult, Aged, Analgesics, Opioid:pharmacology, Base Sequence, Down-Regulation:drug effects, Endothelium, Vascular:drug effects, Estrogen Receptor beta, Female, Gene Expression:drug effects, Humans, In Vitro Techniques, Male, Middle Aged, Molecular Sequence.   

UNLABELLED: Human vascular endothelial cells express the estrogen receptor-beta (ER-beta), which can be modulated by the opiate alkaloid morphine.

OBJECTIVES: To determine if morphine is capable of down regulating the ER-beta receptor in a similar fashion as the mu opiate receptor since they are both coupled to constitutive nitric oxide synthase derived nitric oxide release.

METHODS AND RESULTS: Endothelial cells obtain from human vascular tissues (saphenous vein, atria and primary saphenous vein cells) were treated with 1 uM morphine plus or minus the mu opiate receptor antagonist naloxone or CTOP (10 uM) for 24 h at 37 degrees C. Total RNA was isolated from treated and untreated primary endothelial cells, and specific primers and a probe were used to determine the ER-beta gene expression by real-time RT-PCR. Cells treated with morphine exhibited a down-regulation of ER-beta, whereas naloxone and CTOP were able to partially block the morphine effect. In addition, the 266 bp fragment generated by RT-PCR using the same primers as in the real-time PCR was sequenced and revealed a 100% sequence identity as the authentic ER-beta gene sequence.

CONCLUSIONS: These results indicate that ER-beta is expressed in human vascular endothelial cells, and morphine appears to regulate this receptor in a similar fashion as the mu opiate receptor....

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