Pharmacogenomic analysis of ATP-sensitive potassium channels coexpressing the common type 2 diabetes risk variants E23K and S1369A.
Pharmacogenet Genomics
; 22(3): 206-14, 2012 Mar.
Article
in En
| MEDLINE
| ID: mdl-22209866
ABSTRACT
OBJECTIVES:
The common ATP-sensitive potassium (KATP) channel variants E23K and S1369A, found in the KCNJ11 and ABCC8 genes, respectively, form a haplotype that is associated with an increased risk for type 2 diabetes. Our previous studies showed that KATP channel inhibition by the A-site sulfonylurea gliclazide was increased in the K23/A1369 haplotype. Therefore, we studied the pharmacogenomics of seven clinically used sulfonylureas and glinides to determine their structure-activity relationships in KATP channels containing either the E23/S1369 nonrisk or K23/A1369 risk haplotypes. RESEARCH DESIGN ANDMETHODS:
The patch-clamp technique was used to determine sulfonylurea and glinide inhibition of recombinant human KATP channels containing either the E23/S1369 or the K23/A1369 haplotype.RESULTS:
KATP channels containing the K23/A1369 risk haplotype were significantly less sensitive to inhibition by tolbutamide, chlorpropamide, and glimepiride (IC50 values for K23/A1369 vs. E23/S1369=1.15 vs. 0.71 µmol/l; 4.19 vs. 3.04 µmol/l; 4.38 vs. 2.41 nmol/l, respectively). In contrast, KATP channels containing the K23/A1369 haplotype were significantly more sensitive to inhibition by mitiglinide (IC50=9.73 vs. 28.19 nmol/l for K23/A1369 vs. E23/S1369) and gliclazide. Nateglinide, glipizide, and glibenclamide showed similar inhibitory profiles in KATP channels containing either haplotype.CONCLUSION:
Our results demonstrate that the ring-fused pyrrole moiety in several A-site drugs likely underlies the observed inhibitory potency of these drugs on KATP channels containing the K23/A1369 risk haplotype. It may therefore be possible to tailor existing therapy or design novel drugs that display an increased efficacy in type 2 diabetes patients homozygous for these common KATP channel haplotypes.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Receptors, Drug
/
Tolbutamide
/
Chlorpropamide
/
Gene Expression Regulation
/
ATP-Binding Cassette Transporters
/
Potassium Channels, Inwardly Rectifying
Type of study:
Diagnostic_studies
/
Etiology_studies
/
Risk_factors_studies
Limits:
Humans
Language:
En
Journal:
Pharmacogenet Genomics
Year:
2012
Document type:
Article