The effect of aldose reductase inhibition by JMC-2004 on hyperglycemia-induced endothelial dysfunction.
OBJECTIVE
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.
Papezikova
Ivana
I
Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czech Republic. ivanah@ibp.cz
Pekarova
Michaela
M
Chatzopoulou
Maria
M
Nicolaou
Ioannis
I
Demopoulos
Vassilis
V
Kubala
Lukas
L
Lojek
Antonin
A
D000449:Aldehyde Reductase / Q000037:antagonists & inhibitors*; D000818:Animals; D015153:Blotting, Western; D000001:Calcimycin / Q000494:pharmacology; D002417:Cattle; D002460:Cell Line; D004563:Electrochemistry; D042783:Endothelial Cells / Q000187:drug effects / Q000473:pathology; D004730:Endothelium, Vascular / Q000187:drug effects / Q000473:pathology*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005947:Glucose / Q000494:pharmacology; D005985:Glyceraldehyde / Q000378:metabolism; D017665:Hydroxyl Radical / Q000378:metabolism; D006943:Hyperglycemia / Q000473:pathology*; D049449:Luminescence; D009569:Nitric Oxide / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism; D010545:Peroxides / Q000378:metabolism; D010636:Phenols / Q000494:pharmacology; D011758:Pyrroles / Q000494:pharmacology
C486795:(1-(3,5-difluoro-4-hydroxyphenyl)-1H-pyrrol-3-yl)phenylmethanone; D004791:Enzyme Inhibitors; D010545:Peroxides; D010636:Phenols; D011758:Pyrroles; D009569:Nitric Oxide; D017665:Hydroxyl Radical; D005985:Glyceraldehyde; D000001:Calcimycin; D000449:Aldehyde Reductase; D052250:Nitric Oxide Synthase Type III; D005947:Glucose