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1.
J Endocrinol ; 212(1): 71-84, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22010203

RESUMO

Metabolic syndrome (MetS) and benign prostatic hyperplasia (BPH)/lower urinary tract symptoms (LUTS) are often associated. One of their common denominators is hypogonadism. However, testosterone supplementation is limited by concerns for potential prostatic side effects. The objective was to determine whether MetS-associated prostate alterations are prevented by testosterone supplementation. We used a previously described animal model of MetS, obtained by feeding male rabbits a high-fat diet (HFD) for 12 weeks. Subsets of HFD rabbits were treated with testosterone or with the farnesoid X receptor agonist INT-747. Rabbits fed a standard diet were used as controls. HFD-animals develop hypogonadism and all the MetS features: hyperglycemia, glucose intolerance, dyslipidemia, hypertension, and visceral obesity. In addition, HFD-animals show a prostate inflammation. Immunohistochemical analysis demonstrated that HFD-induced prostate fibrosis, hypoxia, and inflammation. The mRNA expression of several proinflammatory (IL8, IL6, IL1ß, and TNFα), T lymphocyte (CD4, CD8, Tbet, Gata3, and ROR γt), macrophage (TLR2, TLR4, and STAMP2), neutrophil (lactoferrin), inflammation (COX2 and RAGE), and fibrosis/myofibroblast activation (TGFß, SM22α, αSMA, RhoA, and ROCK1/ROCK2) markers was significantly increased in HFD prostate. Testosterone, as well as INT-747, treatment prevented some MetS features, although only testosterone normalized all the HFD-induced prostate alterations. Interestingly, the ratio between testosterone and estradiol plasma level retains a significant, negative, association with all the fibrosis and the majority of inflammatory markers analyzed. These data highlight that testosterone protects rabbit prostate from MetS-induced prostatic hypoxia, fibrosis, and inflammation, which can play a role toward the development/progression of BPH/LUTS.


Assuntos
Androgênios/uso terapêutico , Ácido Quenodesoxicólico/análogos & derivados , Síndrome Metabólica/complicações , Prostatite/prevenção & controle , Testosterona/uso terapêutico , Animais , Biomarcadores/metabolismo , Ácido Quenodesoxicólico/uso terapêutico , Gorduras na Dieta/efeitos adversos , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Estradiol/sangue , Fibrose/metabolismo , Masculino , Próstata/metabolismo , Próstata/patologia , Prostatite/etiologia , Prostatite/metabolismo , Prostatite/patologia , RNA Mensageiro/metabolismo , Coelhos , Receptores Citoplasmáticos e Nucleares/agonistas , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Esteroides/metabolismo , Testosterona/sangue
2.
J Sex Med ; 8(11): 2960-82; quiz 2983, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22032408

RESUMO

INTRODUCTION: The circulation of large amounts of dehydroepiandrosterone (DHEA) and its sulfated derivative (DHEA-S) suggests a physiological role in human physiology. In the central nervous system, DHEA is considered a neurosteroid with a wide range of functions. AIM: The goal of this review is to discuss metabolism, biochemical, and physiological mechanism of DHEA action and the potential role of DHEA in aging and in ameliorating a host of pathological conditions, associated with aging. METHODS: We examined preclinical and clinical data reported in various studies from the available literature concerning the effects of DHEA in normal and pathological conditions. MAIN OUTCOME MEASURES: Data reported in the literature were analyzed, reviewed, and discussed. RESULTS: DHEA mediates its action via multiple signaling pathways involving specific membrane receptors and via transformation into androgen and estrogen derivatives (e.g., androgens, estrogens, 7α and 7ß DHEA, and 7α and 7ß epiandrosterone derivatives) acting through their specific receptors. These pathways include: nitric oxide synthase activation, modulation of γ-amino butyric acid receptors, N-methyl D-aspartate, receptors sigma receptors (Sigma-1), differential expression of inflammatory factors, adhesion molecules and reactive oxygen species, among others. Clinical and epidemiological studies suggested that low DHEA levels might be associated with ischemic heart disease, endothelial dysfunction, atherosclerosis, bone loss, inflammatory diseases, and sexual dysfunction. Most importantly, no significant adverse or negative side effects of DHEA were reported in clinical studies of men and women. CONCLUSIONS: DHEA modulates endothelial function, reduces inflammation, improves insulin sensitivity, blood flow, cellular immunity, body composition, bone metabolism, sexual function, and physical strength in frailty and provides neuroprotection, improves cognitive function, and memory enhancement. DHEA possesses pleiotropic effects and reduced levels of DHEA and DHEA-S may be associated with a host of pathologies; however, the clinical efficacy of DHEA supplementation in ameliorating patho-physiological symptoms remains to be evaluated.


Assuntos
Desidroepiandrosterona/fisiologia , Envelhecimento/fisiologia , Animais , Composição Corporal/fisiologia , Osso e Ossos/metabolismo , Doenças Cardiovasculares/fisiopatologia , Desidroepiandrosterona/biossíntese , Desidroepiandrosterona/metabolismo , Sulfato de Desidroepiandrosterona/metabolismo , Depressão/fisiopatologia , Endotélio Vascular/fisiologia , Feminino , Humanos , Imunidade Celular/fisiologia , Inflamação/fisiopatologia , Masculino , Comportamento Sexual/fisiologia , Pele/metabolismo
3.
J Sex Med ; 7(8): 2698-713, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20412431

RESUMO

INTRODUCTION: In male, lower urinary tract symptoms (LUTS) have been associated, beside benign prostatic hyperplasia, to some unexpected comorbidities (hypogonadism, obesity, metabolic syndrome), which are essentially characterized by an unbalance between circulating androgens/estrogens. Within the bladder, LUTS are linked to RhoA/Rho-kinase (ROCK) pathway overactivity. AIM: To investigate the effects of changing sex steroids on bladder smooth muscle. METHODS: ER α, ER ß, GPR30/GPER1 and aromatase mRNA expression was analyzed in male genitourinary tract tissues, and cells isolated from bladder, prostate, and urethra. Estrogen and G1 effect on RhoA/ROCK signaling output like cell migration, gene expression, and cytoskeletal remodeling, and [Ca(2+) ](i) was also studied in hB cells. Contractile studies on bladder strips from castrated male rats supplemented with estradiol and testosterone was also performed. MAIN OUTCOME MEASURES: The effects of classical (ER α, ER ß) and nonclassical (GPR30/GPER1) estrogen receptor ligands (17 ß-estradiol and G1, respectively) and androgens on RhoA/ROCK-.mediated cell functions were studied in hB cells. Contractility studies were also performed in bladder strips from castrated male rats supplemented with testosterone or estradiol. RESULTS: Aromatase and sex steroid receptors, including GPR30, were expressed in human bladder and mediates several biological functions. Both 17 ß-estradiol and G1 activated calcium transients and induced RhoA/ROCK signaling (cell migration, cytoskeleton remodeling and smooth muscle gene expression). RhoA/ROCK inhibitors blunted these effects. Estrogen-, but not androgen-supplementation to castrated rats increased sensitivity to the ROCK inhibitor, Y-27632 in isolated bladder strips. In hB cells, testosterone elicited effects similar to estrogen, which were abrogated by blocking its aromatization through letrozole. CONCLUSION: Our data indicate for the first time that estrogen-more than androgen-receptors up-regulate RhoA/ROCK signaling. Since an altered estrogen/androgen ratio characterizes conditions, such as aging, obesity and metabolic syndrome, often associated to LUTS, we speculate that a relative hyperestrogenism may induce bladder overactivity through the up-regulation of RhoA/ROCK pathway.


Assuntos
Músculo Liso/fisiopatologia , Hiperplasia Prostática/genética , Hiperplasia Prostática/fisiopatologia , RNA Mensageiro/genética , Obstrução do Colo da Bexiga Urinária/genética , Obstrução do Colo da Bexiga Urinária/fisiopatologia , Bexiga Urinária Hiperativa/genética , Bexiga Urinária Hiperativa/fisiopatologia , Bexiga Urinária/fisiopatologia , Quinases Associadas a rho/genética , Quinases Associadas a rho/fisiologia , Proteína rhoA de Ligação ao GTP/genética , Proteína rhoA de Ligação ao GTP/fisiologia , Androgênios/sangue , Animais , Aromatase/genética , Aromatase/fisiologia , Movimento Celular/genética , Movimento Celular/fisiologia , Células Cultivadas , Citoesqueleto/genética , Citoesqueleto/fisiologia , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/fisiologia , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/fisiologia , Estrogênios/sangue , Genitália Masculina/fisiopatologia , Humanos , Hipogonadismo/genética , Hipogonadismo/fisiopatologia , Masculino , Síndrome Metabólica/genética , Síndrome Metabólica/fisiopatologia , Microscopia Confocal , Obesidade/genética , Obesidade/fisiopatologia , Ratos , Ratos Sprague-Dawley , Receptores de Estrogênio , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/fisiologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Testosterona/sangue , Regulação para Cima/genética , Regulação para Cima/fisiologia
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