Estrogens and male reproduction

The chapter deals with the study of estrogen role in male reproduction, in particulare the role on hypothalamic-pituitary-gonadal axi

MEDICINA OGGI: La terapia delle disfunzioni sessuali nel paziente diabetico

The approach to sexual dysfunction in the diabetic patient is reviewe

Estrogens and male reproduction

n males, estrogens exert pleiotropic effects by acting on several tissue and organs, including the male reproductive system. The action of estrogens is manifest from prenatal life during which the exposure to estrogen excess might influence the development of some structures of the male reproductive tract. Male fertility is under the control of estrogens, especially in rodents. The loss of function of estrogen receptor alpha and/or of the aromatase enzyme leads to infertility in mice. In men, estrogens are able to exert their actions at several levels through the reproductive tract and on several different reproductive cells. However, the regulation of human male reproduction is more complex and the role of estrogens is less clear compared to mice. During fetal and perinatal life, estrogen acts on the central nervous system by modulating the development of some areas within the brain that are committed to controlling male sexual behavior in terms of setting gender identity, sexual orientation development and the evolution of normal adult male sexual behavior. This organizational, central effect of estrogens is of particular significance in other species (especially rodents and rams), being probably less important in men where psychosocial factors become more determining. Other relevant, non-reproductive physiological events depend on estrogen in men and they involve bone maturation and mineralization as well as metabolic functions. In this chapter we provide an update of estrogen\u2019s role in male reproductive function by reviewing the physiological actions of estrogen on male reproduction and the pathophysiology related to estrogen deficiency and estrogen excess. Phenotypes associated with estrogen deficiency and excess in rodents and in man have shed new light on the mechanisms involved in male reproduction, challenging the perception of the predominant importance of androgens in men. It is now clear that the imbalance between estrogen and androgen in men might affect male reproductive function even in presence of normal circulating androgens. Some uncertainties still remain, especially regarding the impact of abnormal serum estrogen levels on male health, particularly due to the fact that estrogen is not routinely measured in men in clinical practice. Advancements in methods to precisely measure estrogens in men, together with a reduction of their costs, should provide better evidence on this issue and inform clinical practice. New basic and clinical research is required to improve our knowledge on the role of estrogen in male reproductive function and men\u2019s health in general. For complete coverage of all related areas of Endocrinology, please see our online FREE web-book, www.endotext.org

Estrogens in males: what have we learned in the last 10 years?

This review focuses on the role of estrogen in men, mainly in male reproduction. The continuing increase in data obtained, and recent discoveries in this area will enable a better understanding of male physiology; these, in turn, will have important clinical implications

The osteoporotic male: Overlooked and undermanaged?

Age-related bone loss in men is a poorly understood phenomenon, although increasing data on the pathophysiology of bone in men is becoming available. Most of what we know on bone pathophysiology derives from studies on women. The well-known association between menopause and osteoporosis is far from been disproven. However, male osteoporosis is a relatively new phenomenon. Its novelty is in part compensated for by the number of studies on female osteoporosis and bone pathophysiology. On the other hand, the deeper understanding of female osteoporosis could lead to an underestimation of this condition in the male counterpart. The longer life-span exposes a number of men to the risk of mild-to-severe hypogonadism which in turn we know to be one of the pathogenetic steps toward the loss of bone mineral content in men and in women. Hypogonadism might therefore be one among many corrigible risk factors such as cigarette smoking and alcohol abuse against which clinicians should act in order to prevent osteoporosis and its complications. Treatments with calcium plus vitamin D and bisphophonates are widely used in men, when osteoporosis is documented and hypogonadism has been excluded. The poor knowledge on male osteoporosis accounts for the lack of well shared protocols for the clinical management of the disease. This review focuses on the clinical approach and treatment strategy for osteoporosis in men with particular attention to its relationship with male hypogonadism

Prevalence and characterization of hypogonadism among men with human immunodeficiency virus infection: preliminary results

Preliminary results on the prevalence of male hypogonadism in HIV-infected me

Effects of treatment for acromegaly on Bone Mineral Density (BMD): is Pegvisomant protective on lumbar BMD?

The abstract deals with the different effects of treatments for acromegaly on bon

Could chronic Vardenafil administration influence the cardiovascular risk in men with type 2 diabetes mellitus?

Introduction Appropriate algorithms for the prediction of cardiovascular risk are strongly suggested in clinical practice, although still controversial. In type 2 diabetes mellitus (T2DM), the benefi- cial effect of phosphodiesterase (PDE)-5 inhibitors is demonstrated on endothelial function but not on the estimation of cardiovascular risk. Aim To study whether the chronic Vardenafil administration to men with T2DM influences vari- ables correlated with the predicted long-term cardiovascular risk calculated by different vali- dated algorithms. Methods Per-protocol analysis of a longitudinal, prospective, randomized, placebo-controlled, dou- ble-blind, investigator-started, clinical trial. 54 male patients affected by T2DM were assigned to study (26patients) and control-group (28patients), respectively. The study included a treatment phase (24weeks) (Vardenafil/placebo 10mg twice-daily) and a follow- up phase (24weeks). Three time points were considered: baseline(V0), end of treatment (V1) and end of the study(V2). Parameters evaluated: endothelial health-related parameters and cardiovascular risk, assessed by calculating the Framingham (coronary hart disease [CHD], myocardial infarction [MI], stroke and cardiovascular disease [CVD]), ASSIGN and CUORE equations. Results Predicted cardiovascular risk at ten years resulted different using the three algorithms cho- sen, without differences between study and control groups and among visits. IL-6 was directly related to CHD, CVD and CUORE scores at V1 and with MI and STROKE at V2. Similarly, hs-CRP was directly related to CHD, MI, STROKE and CUORE only at V1 in the study group. Testosterone serum levels were inversely related to CHD and MI at V1 in study group. Discussion The predicted cardiovascular risk is different depending on the algorithm chosen. Despite no predictive risk reduction after six months of treatment, a possible effect of Vardenafil could be hypothesized through its action on inflammation markers reduction and through restoration of normal testosterone levels

Chronic, long-term administration of Vardenafil improves endothelial function and corrects hypogonadism in patients with type 2 diabetes mellitus. A longitudinal, prospective, randomized, placebo-controlled, double blind, clinical trial

10.1530/endoabs.37.OC4.