Endothelin 1 transciption is controlled by nuclear factor-κB in AGE-stimulated cultured endothelial cells

Incubation of bovine aortic endothelial cells (BAECs) with erythrocytes from patients with type 2 diabetes induced an increase in endothelin 1 (ET-1) production. The effect of erythrocytes on ET-1 synthesis was dependent on glycemic control. ET-1 levels after incubation with erythrocytes derived from patients with HbA(1c) levels <6% were just half the levels observed after incubation with erythrocytes from patients with HbA(1c) levels >8%. N(ε)-(carboxymethyl)lysine (CML)-containing protein isolated from patients' erythrocytes induced ET-1, and CML-containing protein-dependent ET-1 induction was blocked by the recombinant decoy peptide soluble receptor for advanced glycation end products (AGEs), which comprises the NH₂-terminal Ig domain of the receptor for AGEs. In vitro-generated AGEs induced ET-1 mRNA transcription (nuclear run-on assay and Northern blot) in a time- and dose-dependent manner. Transient transfection of BAECs with a chimeric construct containing the 5' promoter region of the ET-1 gene linked to a reporter gene confirmed that AGE induced ET-1 promoter activity. Electrophoretic mobility shift assay confirmed AGE-inducible binding of members of the nuclear factor-κb (NF-κB) family to a potential binding site at -2,090 bp. Binding was functionally significant because overexpression of the cytoplasmic inhibitor of NF-κB or deletion of the NF-κB binding site reduced ET-1 induction, whereas overexpression of NF-κB p65 induced ET-1 even in the absence of AGEs. Thus, ET-1 transcription is controlled by the AGE-inducible redox-sensitive transcription factor NF-κB.