Mair, KM, Wright, AF, Duggan, N, Rowlands, DJ, Hussey, MJ, Roberts, S, Fullerton, J, Nilsen, M, Loughlin, L, Thomas, M and MacLean, MR (2014) Sex-Dependent Influence of Endogenous Estrogen in Pulmonary Hypertension. American Journal of Respiratory and Critical Care Medicine. pp. 456-467.

Abstract

Rationale: The incidence of pulmonary arterial hypertension is greater in women, suggesting estrogens may play a role in the disease pathogenesis. Experimentally, in males, exogenously administered estrogen can protect against pulmonary hypertension (PH). However, in models that display female susceptibility, estrogens may play a causative role.Objectives: To clarify the influence of endogenous estrogen and sex in PH and assess the therapeutic potential of a clinically available aromatase inhibitor.Methods: We interrogated the effect of reduced endogenous estrogen in males and females using the aromatase inhibitor, anastrozole, in two models of PH: the hypoxic mouse and Sugen 5416/hypoxic rat. We also determined the effects of sex on pulmonary expression of aromatase in these models and in lungs from patients with pulmonary arterial hypertension.Measurements and Main Results: Anastrozole attenuated PH in both models studied, but only in females. To verify this effect was caused by reduced estrogenic activity we confirmed that in hypoxic mice inhibition of estrogen receptor alpha also has a therapeutic effect specifically in females. Female rodent lung displays increased aromatase and decreased bone morphogenetic protein receptor 2 and Id1 expression compared with male. Anastrozole treatment reversed the impaired bone morphogenetic protein receptor 2 pathway in females. Increased aromatase expression was also detected in female human pulmonary artery smooth muscle cells compared with male.Conclusions: The unique phenotype of female pulmonary arteries facilitates the therapeutic effects of anastrozole in experimental PH confirming a role for endogenous estrogen in the disease pathogenesis in females and suggests aromatase inhibitors may have therapeutic potential

Item Type:	Article
Additional Information:	NIBR author: Duggan, N institute: NIBR contributor address: Univ Glasgow, Coll Med Vet & Life Sci, Inst Cardiovasc & Med Sci, Glasgow G12 8QQ, Lanark, Scotland mandy.maclean@glasgow.ac.uk; Novartis Inst BioMed Res, Horsham, W Sussex, England
Date Deposited:	13 Oct 2015 13:12
Last Modified:	13 Oct 2015 13:12
URI:	https://oak.novartis.com/id/eprint/24236