Horm Metab Res 2002; 34(11/12): 731-736
DOI: 10.1055/s-2002-38249
Review
© Georg Thieme Verlag Stuttgart · New York

Sex Steroid Biosynthesis in White Adipose Tissue

A.  Meseguer 1 , C.  Puche 1 , A.  Cabero 2
  • 1 Centre d’Investigacions en Bioquímica i Biologia Molecular, Hospital Universitari Vall d’Hebron, Barcelona, Spain
  • 2 Servei de Ginecologia i Obstetricia, Hospital Arnau de Vilanova, Lleida, Spain
Further Information

Publication History

Received 2 October 2002

Accepted after revision 5 December 2002

Publication Date:
27 March 2003 (online)

White Adipose Tissue. General Concepts

White adipose tissue has long been considered a mere storage site for lipids and therefore an energetic reservoir for the maintenance of vital cell functions. When a fall in glucose occurs, lipolysis leads to the release of fatty acids for use by a variety of tissues such as muscle, liver and kidney. Partial oxidation of fatty acids also generates ketones, which serve as an alternate fuel source for the brain and other tissues. Conversely, an increase in glucose and lipids results in increased adipose fatty acid transport and lipogenesis. Fat metabolism depends on energy requirements and is regulated by nutrient, neural and hormonal signals [1].

Obesity and its adverse health consequences constitute an upcoming global epidemic in developed countries that has attracted the attention of the biomedical research community and national health care systems for both scientific and economic reasons. Although it is well-known that obesity prejudices health, it has been recognised that not all patients develop the same metabolic risk profile. While this profile is quite normal in some individuals, severe complications such as insulin resistance, atherogenic dyslipidaemia, type 2 diabetes, hypertension and cardiovascular disease may develop in others. Many studies conducted in the last 20 years have revealed that considerable metabolic heterogeneity exists among various adipose tissue depots, with abdominally obese patients being the subgroup with the highest risk of complications.

The discovery of leptin in the mid-1990s [2] [3] changed the view of adipose tissue to that of a tissue with significant endocrine functions. This secreted circulating factor, known as leptin, is encoded by the ob gene [2], and functions as the signal that reports the state of the body’s energy stores to the brain. Although it is mainly expressed in adipose tissue, low levels of leptin have also been detected in the placenta, skeletal muscle, gastric and mammary epithelium, as well as brain [4] [5] [6]. Leptin has a relative mass of 16 kDa, a helical structure similar to cytokines, and is highly conserved among mammals. Adipose tissue and plasma leptin concentrations are dependent on the amount of energy stored as fat, as well as energy balance status. Leptin is up-regulated by insulin, glucocorticoids, acute infection and pro-inflammatory cytokines, and down-regulated by cold exposure, adrenergic stimulation, GH, thyroid hormone, melatonin and smoking [4] [5] [6]. Leptin expression displays a dimorphic pattern by gender since it is higher in females than in males, due in part to its inhibition by androgens and stimulation by oestrogens [7]. Mutations in the ob gene causing total leptin deficiency may produce hyperphagia, morbid obesity, diabetes, a variety of neuroendocrine abnormalities and autonomic and immune dysfunction [4].

Adipose tissue functions as the major storage depot for triglycerides, but is also an active endocrine organ that senses metabolic signals and secretes hormones that affect the whole body’s energy homeostasis [8] [9] [10]. Apart from leptin, adipocytes are able to secrete tumour necrosis factor alpha [11], plasminogen activator inhibitor (PAI-1) [12], adipsin [13], resistin [14] and adiponectin [15] [16] [17] [18] [19], collectively known as adipocytokines [20]. Other hormones such as angiotensinogen [21] and angiotensin II (AII) [22] have also been described in adipose tissue. Some authors have related the presence of AII with control of adiposity through regulation of lipid synthesis and storage in adipocytes [23]. Others have described the expression of AII receptors in human preadipocytes, claiming that AII has early, receptor-mediated effects on cell cycle progression in human preadipocytes that may contribute to their differentiation to the adipocyte phenotype [24].

Since all these products have been implicated in metabolic, neuroendocrine, immune and cardiovascular regulation [25], it is of great interest to understand the endocrine actions of products secreted by adipose tissue and their potential role in disease.

References

  • 1 Spiegelman B M, Flier J S. Adipogenesis and obesity: rounding out the big picture.  Cell. 1996;  87 377-389
  • 2 Zhang Y, Proenca R, Maffei M, Barone M, Leopold L, Friedman J M. Positional cloning of the mouse obese gene and its human homologue.  Nature. 1994;  372 425-432
  • 3 Chen H, Charlat O, Tartaglia L A, Woolf E A, Weng X, Ellis S J, Lakey N D, Culpepper J, Moore K J, Breitbart R E, Duyk G M, Tepper R I, Morgenstern J P. Evidence that the diabetes gene encodes the leptin receptor: identification of a mutation in the leptin receptor gene in db/db mice.  Cell. 1996;  84 491-495
  • 4 Friedman J M, Halaas J L. Leptin and the regulation of body weight in mammals.  Nature. 1998;  395 763-770
  • 5 Flier J S. Clinical review 94: What’s in a name? In search of leptin’s physiologic role.  J Clin Endocrinol Metab. 1998;  83 407-1413
  • 6 Ahima R S, Flier J S. Leptin.  Annu Rev Physiol. 2000;  62 413-437
  • 7 Rosenbaum M, Leibel R L. Clinical review 107: Role of gonadal steroids in the sexual dimorphisms in body composition and circulating concentrations of leptin.  J Clin Endocrinol Metab. 1999;  84 1784-1789
  • 8 Mohamed-Ali V, Pinkney J H, Coppack S W. Adipose tissue as an endocrine and paracrine organ.  Int J Obes Relat Metab Disord. 1998;  22 1145-1158
  • 9 Havel P J. Control of energy homeostasis and insulin action by adipocyte hormones: leptin, acylation stimulating protein, and adiponectin.  Curr Opin Lipidol. 2002;  13 51-59
  • 10 Ahima R S, Flier J S. Adipose tissue as an endocrine organ.  Trends Endocrinol Metab. 2000;  11 327-332
  • 11 Hotamisligil G S. The role of TNF-alpha and TNF receptors in obesity and insulin resistance.  J Intern Med. 1999;  245 621-625
  • 12 Shimomura I, Funahashi T, Takahashi M, Maeda K, Kotani K, Nakamura T, Yamashita S, Miura M, Fukuda Y, Takemura K, Tokunaga K, Matsuzawa Y. Enhanced expression of PAI-1 in visceral fat: possible contributor to vascular disease in obesity.  Nat Med. 1996;  2 800-803
  • 13 White R T, Damm D, Hancock N, Rosen B S, Lowell B B, Usher P, Flier J S, Spiegelman B M. Human adipsin is identical to complement factor D and is expressed at high levels in adipose tissue.  J Biol Chem. 1992;  267 9210-9213
  • 14 Steppan C M, Bailey S T, Bhat S, Brown E J, Banerjee R R, Wright C M, Patel H R, Ahima R S, Lazar M A. The hormone resistin links obesity to diabetes.  Nature. 2001;  409 307-312
  • 15 Maeda K, Okubo K, Shimomura I, Funahashi T, Matsuzawa Y, Matsubara K. cDNA cloning and expression of a novel adipose specific collagen-like factor, apM1 (AdiPose Most abundant Gene transcript 1).  Biochem Biophys Res Commun. 1996;  221 286-289
  • 16 Scherer P E, Williams S, Fogliano M, Baldini G, Lodish H F. A novel serum protein similar to C1q, produced exclusively in adipocytes.  J Biol Chem. 1995;  270 26 746-26 749
  • 17 Hu E, Liang P, Spiegelman B M. AdipoQ is a novel adipose-specific gene dysregulated in obesity.  J Biol Chem. 1996;  271 0697-10 703
  • 18 Nakano Y, Tobe T, Choi-Miura N H, Mazda T, Tomita M. Isolation and characterization of GBP28, a novel gelatin-binding protein purified from human plasma.  J Biochem (Tokyo). 1996;  120 803-812
  • 19 Yamauchi T, Kamon J, Waki H, Terauchi Y, Kubota N, Hara K, Mori Y, Ide T, Murakami K, Tsuboyama-Kasaoka N, Ezaki O, Akanuma Y, Gavrilova O, Vinson C, Reitman M L, Kagechika H, Shudo K, Yoda M, Nakano Y, Tobe K, Nagai R, Kimura S, Tomita M, Froguel P, Kadowaki T. The fat-derived hormone adiponectin reverses insulin resistance associated with both lipoatrophy and obesity.  Nat Med. 2001;  7 941-946
  • 20 Matsuzawa Y, Funahashi T, Nakamura T. Molecular mechanism of metabolic syndrome X: contribution of adipocytokines adipocyte-derived bioactive substances.  Ann N Y Acad Sci. 1999;  892 146-154
  • 21 Jones B H, Standridge M K, Taylor J W, Moustaid N. Angiotensinogen gene expression in adipose tissue: analysis of obese models and hormonal and nutritional control.  Am J Physiol. 1997;  273 (1 Pt 2) R236-R242
  • 22 Saye J A, Ragsdale N V, Carey R M, Peach M J. Localization of angiotensin peptide-forming enzymes of 3T3-F442A adipocytes.  Am J Physiol. 1993;  264 (6 Pt 1) C1570-C1576
  • 23 Jones B H, Standridge M K, Moustaid N. Angiotensin II increases lipogenesis in 3T3-L1 and human adipose cells.  Endocrinology. 1997;  138 1512-1519
  • 24 Crandall D L, Armellino D C, Busler D E, McHendry-Rinde B, Kral J G. Angiotensin II receptors in human preadipocytes: role in cell cycle regulation.  Endocrinology. 1999;  140 154-158
  • 25 Lawrence V J, Coppack S W. The endocrine function of the fat cell-regulation by the sympathetic nervous system.  Horm Metab Res. 2000;  32 453-467
  • 26 Lapidus L, Bengtsson C, Larsson B, Pennert K, Rybo E, Sjöström L. Distribution of adipose tissue and risk of cardiovascular disease and death: a 12-year follow up of participants in the population study of women in Gothenburg, Sweden.  Br Med J. 1984;  289 1257-1261
  • 27 Larsson B, Svardsudd K, Welin L, Wilhelmsen L, Björntorp P, Tibblin G. Abdominal adipose tissue distribution, obesity, and risk of cardiovascular disease and death: 13-year follow up of participants in the study of men born in 1913.  Br Med J. 1984;  288 1401-1404
  • 28 Ohlson L O, Larsson B, Svardsudd K, Welin L, Eriksson H, Wilhelmsen L, Bjorntorp P, Tibblin G. The influence of body fat distribution on the incidence of diabetes mellitus. 13.5 years of follow-up of the participants in the study of men born in 1913.  Diabetes. 1985;  34 1055-1058
  • 29 Ducimetière P, Richard J, Cambien F. The pattern of subcutaneous fat distribution in middle-aged men and the risk of coronary heart disease: the Paris Prospective Study.  Int J Obes. 1986;  10 229-240
  • 30 Donahue R P, Abbott R D, Bloom E, Reed D M, Yano K. Central obesity and coronary heart disease in men.  Lancet. 1987;  1 821-824
  • 31 Björntorp P. Hazards in subgroups of human obesity.  Eur J Clin Invest. 1984;  14 239-241
  • 32 Kissebah A H, Vydelingum N, Murray R, Evans D J, Hartz A J, Kalkhoff R K, Adams P W. Relation of body fat distribution to metabolic complications of obesity.  J Clin Endocrinol Metab. 1982;  54 254-260
  • 33 Folsom A R, Kaye S A, Sellers T A, Hong C P, Cerhan J R, Potter J D, Prineas R J. Body fat distribution and 5-year risk of death in older women.  JAMA. 1993;  269 483-487
  • 34 Kissebah A H, Peiris A N. Biology of regional body fat distribution: relationship to non-insulin-dependent diabetes mellitus.  Diabetes Metab Rev. 1989;  5 83-109
  • 35 Kissebah A H, Freedman D S, Peiris A N. Health risks of obesity.  Med Clin North Am. 1989;  73 111-138
  • 36 Bolinder J, Kager L, Ostman J, Arner P. Differences at the receptor and postreceptor levels between human omental and subcutaneous adipose tissue in the action of insulin on lipolysis.  Diabetes. 1983;  32 117-123
  • 37 Björntorp P. “Portal” adipose tissue as a generator of risk factors for cardiovascular disease and diabetes.  Arteriosclerosis. 1990;  10 493-496
  • 38 Hennes M M, Shrago E, Kissebah A H. Receptor and postreceptor effects of free fatty acids (FFA) on hepatocyte insulin dynamics.  Int J Obes. 1990;  14 831-841
  • 39 Svedberg J, Björntorp P, Smith U, Lonnroth P. Free-fatty acid inhibition of insulin binding, degradation, and action in isolated rat hepatocytes.  Diabetes. 1990;  39 570-574
  • 40 Després J P. Obesity and lipid metabolism: revelance of body fat distribution.  Curr Opin Lipidol. 1991;  2 5-15
  • 41 Després J P, Marette A. Relation of components of insulin resistance syndrome to coronary disease risk.  Curr Opin Lipidol. 1994;  5 274-289
  • 42 Tchernof A, Després J P. Sex steroid hormones, sex hormone-binding globulin, and obesity in men and women.  Horm Metab Res. 2000;  32 526-536
  • 43 Vague J. La différenciation sexuelle, facteur determinant des formes de l’obésite.  Press Med. 1947;  55 339-340
  • 44 Kalin M F, Zumoff B. Sex hormones and coronary disease: a review of the clinical studies.  Steroids. 1990;  55 330-352
  • 45 Barrett-Connor E. Heart disease in women.  Fertil Steril. 1994;  62 (Suppl. 2) 127S-132S
  • 46 Gambacciani M, Ciaponi M, Cappagli B, Piaggesi L, de Simone L, Orlandi R, Genazzani A R. Body weight, body fat distribution, and hormonal replacement therapy in early postmenopausal women.  J Clin Endocrinol Metab. 1997;  82 414-417
  • 47 Morishima A, Grumbach M M, Simpson E R, Fisher C, Qin K. Aromatase deficiency in male and female siblings caused by a novel mutation and the physiological role of estrogens.  J Clin Endocrinol Metab. 1995;  80 3689-3698
  • 48 Carani C, Qin K, Simoni M, Faustini-Fustini M, Serpente S, Boyd J, Korach K S, Simpson E R. Effect of testosterone and estradiol in a man with aromatase deficiency.  N Engl J Med. 1997;  337 91-95
  • 49 Bilezikian J P, Morishima A, Bell J, Grumbach M M. Increased bone mass as a result of estrogen therapy in a man with aromatase deficiency.  N Engl J Med. 1998;  339 599-603
  • 50 Conte F A, Grumbach M M, Ito Y, Fisher C R, Simpson E R. A syndrome of female pseudohermaphrodism, hypergonadotropic hypogonadism, and multicystic ovaries associated with missense mutations in the gene encoding aromatase (P450arom).  J Clin Endocrinol Metab. 1994;  78 1287-1292
  • 51 Fisher C R, Graves K H, Parlow A F, Simpson E R. Characterization of mice deficient in aromatase (ArKO) because of targeted disruption of the cyp19 gene.  Proc Natl Acad Sci U S A. 1998;  95 6965-6970
  • 52 Jones M E, Thorburn A W, Britt K L, Hewitt K N, Wreford N G, Proietto J, Oz O K, Leury B J, Robertson K M, Yao S, Simpson E R. Aromatase-deficient (ArKO) mice have a phenotype of increased adiposity.  Proc Natl Acad Sci USA. 2000;  97 12 735-12 740
  • 53 Wade G N. Gonadal hormones and behavioral regulation of body weight.  Physiol Behav. 1972;  8 523-534
  • 54 Heine P A, Taylor J A, Iwamoto G A, Lubahn D B, Cooke P S. Increased adipose tissue in male and female estrogen receptor-alpha knockout mice.  Proc Natl Acad Sci USA. 2000;  97 12 729-12 734
  • 55 Couse J F, Korach K S. Estrogen receptor null mice: what have we learned and where will they lead us?.  Endocr Rev. 1999;  20 358-417
  • 56 Darimont C, Delansorne R, Paris J, Ailhaud G, Negrel R. Influence of estrogenic status on the lipolytic activity of parametrial adipose tissue in vivo: an in situ microdialysis study.  Endocrinology. 1997;  138 1092-1096
  • 57 Hansen F M, Fahmy N, Nielsen J H. The influence of sexual hormones on lipogenesis and lipolysis in rat fat cells.  Acta Endocrinol. 1980;  95 566-570
  • 58 Shimizu H, Ohtani K, Kato Y, Tanaka Y, Mori M. Withdrawal of [corrected] estrogen increases hypothalamic neuropeptide Y (NPY) mRNA expression in ovariectomized obese rat .  Neurosci Lett. 1996;  204 81-84
  • 59 Haas D A, George S R. Gonadal regulation of corticotropin-releasing factor immunoreactivity in hypothalamus.  Brain Res Bull. 1988;  20 361-367
  • 60 Wing R R, Matthews K A, Kuller L H, Meilahn E N, Plantinga P L. Weight gain at the time of menopause.  Arch Intern Med. 1991;  151 97-102
  • 61 Pasquali R, Casimirri F, Labate A M, Tortelli O, Pascal G, Anconetani B, Gatto M R, Flamia R, Capelli M, Barbara L. Body weight, fat distribution and the menopausal status in women.  Int J Obes Relat Metab Disord. 1994;  18 614-621
  • 62 Grodin J M, Siiteri P K, Macdonald P C. Source of estrogen production in postmenopausal women.  J Clin Endocrinol Metab. 1973;  36 207-214
  • 63 Hemsell D L, Grodin J M, Brenner P F, Siiteri P K, MacDonald P C. Plasma precursors of estrogen. II. Correlation of the extent of conversion of plasma androstenedione to estrone with age.  J Clin Endocrinol Metab. 1974;  38 476-479
  • 64 Edman C D, MacDonald P C. Effect of obesity on conversion of plasma androstenedione to estrone in ovulatory and anovulator young women.  Am J Obstet Gynecol. 1978;  130 456-461
  • 65 Simpson E R, Mendelson C R. Effect of aging and obesity on aromatase activity of human adipose cells.  Am J Clin Nutr. 1987;  45 290-295
  • 66 Cleland W H, Mendelson C R, Simpson E R. Effects of aging and obesity on aromatase activity of human adipose cells.  J Clin Endocrinol Metab. 1985;  60 174-177
  • 67 Bulun S E, Simpson E R. Competitive reverse transcription-polymerase chain reaction analysis indicates that levels of aromatase cytochrome P450 transcripts in adipose tissue of buttocks, thighs, and abdomen of women increase with advancing age.  J Clin Endocrinol Metab. 1994;  78 428-432
  • 68 Miller W R, O’Neill J. The importance of local synthesis of estrogen within the breast.  Steroids. 1987;  50 537-548
  • 69 Edman C D, Macdonald P C. The role of extraglandular estrogen in women in health and disease. In: VHT James VHT, Serio M, Giusti G (eds) The Endocrine Function of the Human Ovary. Academic Press London; 1976: 135-140
  • 70 James V HT, Serio M, Giusti G. The endocrine function of the human ovary. London; Academic Press 1976: 135-140
  • 71 Clyne C D, Speed C J, Zhou J, Simpson E R. Liver receptor homologue-1 (LRH-1) regulates expression of aromatase in preadipocytes.  J Biol Chem. 2002;  277 20 591-20 597
  • 72 Horton R, Tait J F. Androstenedione production and interconversion rates measured in peripheral blood and studies on the possible site of its conversion to testosterone.  J Clin Invest. 1966;  45 301-313
  • 73 Bardin C W, Lipsett M B. Testosterone and androstenedione blood production rates in normal women and women with idiopathic hirsutism or polycystic ovaries.  J Clin Invest. 1967;  46 891-902
  • 74 Bleau G, Roberts K D, Chapdelaine A. The in vitro and in vivo uptake and metabolism of steroids in human adipose tissue.  J Clin Endocrinol Metab. 1974;  39 236-246
  • 75 Martel C, Rhéaume E, Takahashi M, Trudel C, Couet J, Luu-The V, Simard J, Labrie F. Distribution of 17 beta-hydroxysteroid dehydrogenase gene expression and activity in rat and human tissues.  J Steroid Biochem Mol Biol. 1992;  41 597-603
  • 76 Corbould A M, Judd S J, Rodgers R J. Expression of types 1, 2, and 3 17 beta-hydroxysteroid dehydrogenase in subcutaneous abdominal and intra-abdominal adipose tissue of women.  J Clin Endocrinol Metab. 1998;  83 187-194
  • 77 Corbould A M, Bawden M J, Lavranos T C, Rodgers R J, Judd S J. The effect of obesity on the ratio of type 3-17beta-hydroxysteroid dehydrogenase mRNA to cytochrome P450 aromatase mRNA in subcutaneous abdominal and intra-abdominal adipose tissue of women.  Int J Obes Relat Metab Disord. 2002;  26 165-175
  • 78 Miller L K, Kral J G, Strain G W, Zumoff B. Androgen binding to ammonium sulfate precipitates of human adipose tissue cytosols.  Steroids. 1990;  55 410-415
  • 79 Pedersen S B, Fuglsig S, Sjogren P, Richelsen B. Identification of steroid receptors in human adipose tissue.  Eur J Clin Invest. 1996;  26 1051-1056
  • 80 Eagon P K, Elm M S, Stafford E A, Porter L E. Androgen receptor in human liver: characterization and quantitation in normal and diseased liver.  Hepatology. 1994;  19 92-100
  • 81 Cohen C, Lawson D, DeRose P B. Sex and androgenic steroid receptor expression in hepatic adenomas.  Hum Pathol. 1998;  29 1428-1432
  • 82 Xu X, de Pergola G, Bjorntorp P. The effects of androgens on the regulation of lipolysis in adipose precursor cells.  Endocrinology. 1990;  126 1229-1234
  • 83 Xu X F, de Pergola G, Bjorntorp P. Testosterone increases lipolysis and the number of beta-adrenoceptors in male rat adipocytes.  Endocrinology. 1991;  128 379-382
  • 84 Lönnqvist F, Thome A, Nilsell K, Hoffstedt J, Arner P. A pathogenic role of visceral fat beta 3-adrenoceptors in obesity.  J Clin Invest. 1995;  95 1109-1116
  • 85 Ushiroyama T, Sugimoto O. Endocrine function of the peri- and postmenopausal ovary.  Horm Res. 1995;  44 64-68
  • 86 Jose M, Puche C, Cabero A, Cabero L, Meseguer A. Expression of P450c17 messenger ribonucleic acid in postmenopausal human ovary tissues.  Fertil Steril. 1999;  71 528-535
  • 87 Martel C, Melner M H, Gagne D, Simard J, Labrie F. Widespread tissue distribution of steroid sulfatase, 3-beta-hydroxysteroid dehydrogenase/delta 5-delta 4 isomerase (3-beta-HSD), 17-beta-HSD 5 alpha-reductase and aromatase activities in the rhesus monkey.  Mol Cell Endocrinol. 1994;  104 103-111
  • 88 Simard J, Melner M H, Breton N, Low K G, Zhao H F, Periman L M, Labrie F. Characterization of macaque 3 beta-hydroxy-5-ene steroid dehydrogenase/delta 5-delta 4 isomerase: structure and expression in steroidogenic and peripheral tissues in primate.  Mol Cell Endocrinol. 1991;  75 101-110
  • 89 Puche C, Jose M, Cabero A, Meseguer A. Expression and enzymatic activity of the P450c17 gene in human adipose tissue.  Eur J Endocrinol. 2002;  146 223-229
  • 90 Pasquali R, Casimirri F, Venturoli S, Antonio M, Morselli L, Reho S, Pezzoli A, Paradisi R. Body fat distribution has weight-independent effects on clinical, hormonal, and metabolic features of women with polycystic ovary syndrome.  Metabolism. 1994;  43 706-713
  • 91 Mahendroo M S, Mendelson C R, Simpson E R. Tissue-specific and hormonally controlled alternative promoters regulate aromatase cytochrome P450 gene expression in human adipose tissue.  J Biol Chem. 1993;  268 19 463-19 470
  • 92 Agarwal V R, Ashanullah C I, Simpson E R, Bulun S E. Alternatively spliced transcripts of the aromatase cytochrome P450 (CYP19) gene in adipose tissue of women.  J Clin Endocrinol Metab. 1997;  82 70-74

Dr. A. Meseguer

Centre d’Investigacions en Bioquímica i Biologia Molecular (CIBBIM) ·

Hospital Universitari Vall d’Hebron · Pg. Vall d’Hebron 119-129 · 08035 Barcelona · Spain ·

Phone: + 34 (93) 489-40 61

Fax: + 34 (93) 489-40 64

Email: meseguer@hg.vhebron.es

    >