Weight gain and inflammation regulate aromatase expression in male adipose tissue, as evidenced by reporter gene activity L. Polari a,b , E. Yatkin a,b , M.G. Martínez Chacón a,b , M. Ahotupa c , A. Smeds d , L. Strauss b,e , F. Zhang b,e , M. Poutanen b,e , N. Saarinen a,b,e , S.I. Mäkelä a,b, * a Functional Foods Forum, University of Turku, Turku, Finland b Turku Center for Disease Modeling, Institute of Biomedicine, University of Turku, Turku, Finland c Research Centre of Applied and Preventive Cardiovascular Medicine, University of Turku, Turku, Finland d Åbo Akademi University, Process Chemistry Centre, Laboratory of Wood and Paper Chemistry, Turku, Finland e Department of Physiology, Institute of Biomedicine, University of Turku, Finland ARTICLE INFO Article history: Received 19 February 2015 Received in revised form 11 May 2015 Accepted 1 June 2015 Available online Keywords: Aromatase White adipose tissue Inflammation Obesity Polyphenols Lignans A B ST R AC T Obesity and white adipose tissue (WAT) inflammation are associated with enhanced aromatization in women, but little is known about the regulation of aromatase (CYP19A1) gene expression in male WAT. We investigated the impact of weight gain and WAT inflammation on the regulation of CYP19A1 in males, by utilizing the hARO-Luc aromatase reporter mouse model containing a >100-kb 5′-region of the human CYP19A1 gene. We show that hARO-Luc reporter activity is enhanced in WAT of mice with increased ad- iposity and inflammation. Dexamethasone and TNFα, as well as forskolin and phorbol 12-myristate 13- acetate, upregulate hARO-Luc activity, suggesting the involvement of promoters I.4 and I.3/II. Furthermore, we show that diet enriched with antioxidative plant polyphenols attenuates WAT inflammation and hARO- Luc activity in obese males. In conclusion, our data suggest that obesity-associated WAT inflammation leads to increased peripheral CYP19A1 expression in males, and that polyphenol-enriched diet may have the potential to attenuate excessive aromatization in WAT of obese men. © 2015 Published by Elsevier Ireland Ltd. 1. Introduction The final step in the biosynthesis of estrogens is catalyzed by the cytochrome P450 aromatase (CYP19A1) enzyme, which converts an- drostenedione and testosterone (T) to estrone and estradiol (E2), respectively. In humans, white adipose tissue (WAT) is an impor- tant site for extragonadal aromatization and estrogen production, and it has been estimated that 80% of E2 in men is produced in extragonadal tissues (MacDonald et al., 1979). Increase in WAT mass, thus, leads into increased peripheral conversion of androgens to es- trogens. Moreover, obesity-associated inflammatory factors upregulate aromatase gene expression in WAT of women (Morris et al., 2011; Subbaramaiah et al., 2012), indicating that low-grade inflammation further contributes to increased estrogen biosynthe- sis in WAT of obese individuals. Very little, however, is known about the regulation of CYP19A1 gene expression, or the effects of locally produced estrogens in male WAT. Excessive estrogen production in WAT of obese men can be pos- tulated to play a role in the development of various disorders, such as male obesity-associated secondary hypogonadism (Tajar et al., 2012) and breast cancer (Liukkonen et al., 2010). Obesity is asso- ciated with elevated serum E2/T ratio in men (Dobs et al., 2001; Foresta et al., 2009), and aromatase inhibitors normalize T levels in hypogonadal obese men (de Ronde and de Jong, 2011). In order to understand the pathophysiology of obesity-related endocrine dysregulation in men, and to develop effective interventions, it is necessary to define the mechanisms by which adiposity, inflam- mation and dietary factors regulate the expression of CYP19A1 in male WAT. These mechanisms are difficult to study in human sub- jects, and experimental studies in vivo have been hampered by the lack of appropriate rodent models, due to the critical differences in the regulatory regions of human and rodent CYP19A1 genes (Zhao et al., 2009). Human CYP19A1 gene is widely expressed in extragonadal tissues, and consists of at least 11 noncoding first exons, alternatively expressed in different tissues and each controlled by distinct sets of cytokines and hormones (Demura et al., 2008; Simpson et al., 2002). In rodent aromatase gene, the regulatory region is less complex, and lacks several of the first exons that drive extragonadal aromatase expression in humans (Golovine et al., 2003). Abbreviations: CLS, crown like structure; DEX, dexamethasone; E2, 17β- estradiol; FSK, forskolin; HFD, high fat diet; GF, gonadal fat tissue; LFD, low fat diet; Luc, luciferase; MSC, mesenchymal stromal cell; PKE, pine knot extract; PMA, phorbol 12-myristate 13-acetate; SCF, subcutaneous fat tissue; T, testosterone; WAT, white adipose tissue. * Corresponding author. Functional Foods Forum, University of Turku, 20520 Turku, Finland. Tel.: +358 405143714. E-mail address: sarmak@utu.fi (S.I. Mäkelä). http://dx.doi.org/10.1016/j.mce.2015.06.002 0303-7207/© 2015 Published by Elsevier Ireland Ltd. Molecular and Cellular Endocrinology ■■ (2015) ■■–■■ ARTICLE IN PRESS Please cite this article in press as: L. Polari, et al.,Weight gain and inflammation regulate aromatase expression in male adipose tissue, as evidenced by reporter gene activity, Mo- lecular and Cellular Endocrinology (2015), doi: 10.1016/j.mce.2015.06.002 Contents lists available at ScienceDirect Molecular and Cellular Endocrinology journal homepage: www.elsevier.com/locate/mce Q2 Q1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89