Role of transcription factors in estrogen‐dependent upregulation of CYP 2C family in arteries of eNOS deficient mice

Abstract

Upregulation of cytochrome P450 (CYP) 2C29/38/40 is responsible for the EET‐mediated flow‐dependent dilation in microvessels of female mice, as a function of NO deficiency. In the present studies, we provide evidence of the correlation between transcription factors (PPAR‐γ, PPAR‐δ and RXR‐γ) and CYP 2C29/38/40 in isolated arterioles of female eNOS‐KO mice by microarray (SuperArray, OMM‐401). Five single arterioles isolated from mesentery of both genders of eNOS‐KO and WT mice were pooled and snap frozen in liquid nitrogen; ∼10 μg of total RNA were isolated, and a total of 10 arrays from 2 WT and 3 eNOS‐KO mice of each gender were performed. Microarray results indicate that associated with a specific upregulation of CYP 2C29/38/40, expression of genes for PPAR‐γ, PPAR‐δ and RXR‐γ, the nuclear receptors that function as gene regulators via specific DNA binding, was also increased (P<0.01, 0.05 and 0.03, respectively) in female eNOS‐KO compared to male eNOS‐KO vessels. These significant differences were validated by quantitative real‐time PCR and Western blot analysis. The increase in gene expression for the three transcription factors was only observed in vessels of female, but not in those of male eNOS‐KO mice, and without significant differences between vessels of WT male and WT female mice, a pattern that is similar to the upregulation of CYP 2C/29/38/40. Thus, the microarray analysis screened the global expression of genes for the transcription factors and revealed the specificity of estrogen and NO deficiency in the control of the transcription factors which may play a role in the regulation of CYP 2C expression (Supported by NIH HL‐43023, HL‐68813 and HL‐070653).