Torcetrapib induces aldosterone and cortisol production by an intracellular calcium-mediated mechanism independently of cholesteryl ester transfer protein inhibition.

Article Details

Citation

Hu X, Dietz JD, Xia C, Knight DR, Loging WT, Smith AH, Yuan H, Perry DA, Keiser J

Torcetrapib induces aldosterone and cortisol production by an intracellular calcium-mediated mechanism independently of cholesteryl ester transfer protein inhibition.

Endocrinology. 2009 May;150(5):2211-9. doi: 10.1210/en.2008-1512. Epub 2009 Jan 22.

PubMed ID
19164467 [ View in PubMed
]
Abstract

ILLUMINATE (Investigation of Lipid Level Management to Understand its Impact in Atherosclerotic Events), the phase 3 morbidity and mortality trial of torcetrapib, a cholesteryl ester transfer protein (CETP) inhibitor, identified previously undescribed changes in plasma levels of potassium, sodium, bicarbonate, and aldosterone. A key question after this trial is whether the failure of torcetrapib was a result of CETP inhibition or of some other pharmacology of the molecule. The direct effects of torcetrapib and related molecules on adrenal steroid production were assessed in cell culture using the H295R as well as the newly developed HAC15 human adrenal carcinoma cell lines. Torcetrapib induced the synthesis of both aldosterone and cortisol in these two in vitro cell systems. Analysis of steroidogenic gene expression indicated that torcetrapib significantly induced the expression of CYP11B2 and CYP11B1, two enzymes in the last step of aldosterone and cortisol biosynthesis pathway, respectively. Transcription profiling indicated that torcetrapib and angiotensin II share overlapping pathways in regulating adrenal steroid biosynthesis. Hormone-induced steroid production is mainly mediated by two messengers, calcium and cAMP. An increase of intracellular calcium was observed after torcetrapib treatment, whereas cAMP was unchanged. Consistent with intracellular calcium being the key mediator of torcetrapib's effect in adrenal cells, calcium channel blockers completely blocked torcetrapib-induced corticoid release and calcium increase. A series of compounds structurally related to torcetrapib as well as structurally distinct compounds were profiled. The results indicate that the pressor and adrenal effects observed with torcetrapib and related molecules are independent of CETP inhibition.

DrugBank Data that Cites this Article

Drug Enzymes
DrugEnzymeKindOrganismPharmacological ActionActions
TorcetrapibCytochrome P450 11B2, mitochondrialProteinHumans
Unknown
Inducer
Details
Pharmaco-transcriptomics
DrugDrug GroupsGeneGene IDChangeInteractionChromosome
ColforsinExperimental InvestigationalCYP11B11584
upregulated
Colforsin results in increased expression of CYP11B1 mRNA8q24.3
ColforsinExperimental InvestigationalCYP11B21585
upregulated
Colforsin results in increased expression of CYP11B2 mRNA8q24.3
TorcetrapibInvestigationalCREM1390
upregulated
torcetrapib results in increased expression of CREM mRNA10p11.21
TorcetrapibInvestigationalCYP11B11584
upregulated
torcetrapib results in increased expression of CYP11B1 mRNA8q24.3
TorcetrapibInvestigationalCYP11B21585
upregulated
torcetrapib results in increased expression of CYP11B2 mRNA8q24.3
TorcetrapibInvestigationalCYR613491
upregulated
torcetrapib results in increased expression of CYR61 mRNA1p22.3
TorcetrapibInvestigationalGEM2669
upregulated
torcetrapib results in increased expression of GEM mRNA8q22.1
TorcetrapibInvestigationalNR4A13164
upregulated
torcetrapib results in increased expression of NR4A1 mRNA12q13.13
TorcetrapibInvestigationalNR4A24929
upregulated
torcetrapib results in increased expression of NR4A2 mRNA2q22-q23
TorcetrapibInvestigationalNR4A38013
upregulated
torcetrapib results in increased expression of NR4A3 mRNA9q22
TorcetrapibInvestigationalPPIA5478
upregulated
torcetrapib results in increased expression of PPIA mRNA7p13
TorcetrapibInvestigationalRHOB388
upregulated
torcetrapib results in increased expression of RHOB mRNA2p24.1
TorcetrapibInvestigationalUSP47375
upregulated
torcetrapib results in increased expression of USP4 mRNA3p21.31
TorcetrapibInvestigationalZNF33155422
upregulated
torcetrapib results in increased expression of ZNF331 mRNA19q13