Hormonal Regulation of Puberty and Fertility
Endocrine DiseaseInfertility3 moreBackground: - The body produces gonadotropin-releasing hormone (GnRH) about every 2 hours. GnRH travels through the bloodstream to the pituitary gland, where it stimulates the gland to produce hormones called gonadotropins. These hormones stimulate the testicles or ovaries. The testicles produce testosterone and develop sperm. The ovaries produce estrogen and prepare for ovulation. Normal estrogen and testosterone levels are required for puberty. Some people, however, have either low levels or total lack of GnRH. This can cause problems with puberty and fertility. Researchers want to study people with low or no GnRH to better understand how it affects puberty and fertility. Objectives: - To study disorders of GnRH production. Eligibility: Adult men and women at least 18 years of age with low or no gonadotropin levels. Adolescents between 14 and 18 years of age with low or no gonadotropin levels. Design: Participants will be screened with a physical exam and medical history. Blood and urine samples will be collected. Participants will have tests to look at their hormone levels. Blood samples may be collected after taking different drugs, including insulin and cortisone. A 24-hour urine sample will be collected. Participants will have imaging studies to look at bone and brain development. They will also have ultrasounds of the kidneys, abdomen, and reproductive organs. Tests of smell and hearing will be used to look for abnormalities in these senses.
Cardiovascular Outcomes of Low Testosterone
HypogonadismThis study plans to learn more about heart and vascular aging in men. In some men as they get older, testosterone levels fall below the normal range for young men. Also, as men get older cardiovascular health worsens. This can lead to high blood pressure and heart disease. In this study we want to find out what causes cardiovascular health to worsen in older men. Also we want to find out what happens when testosterone levels are lowered for a short time. Specifically, we want to see if the reduction in cardiovascular health in older men with low testosterone levels is because of damage to mitochondria. Mitochondria are the main power supply of the cells in our body. The results from this study will help to understand why cardiovascular health declines in older men with low testosterone levels compared to younger men and older men who have higher testosterone levels. Knowing this information will help to develop therapies to prevent heart disease in men.
The Molecular Basis of Inherited Reproductive Disorders
Hypogonadotropic HypogonadismReproductive Disorder2 moreThe goal of this study is to learn more about the genes that control puberty and reproduction in humans.
Rare Disease Patient Registry & Natural History Study - Coordination of Rare Diseases at Sanford...
Rare DisordersUndiagnosed Disorders316 moreCoRDS, or the Coordination of Rare Diseases at Sanford, is based at Sanford Research in Sioux Falls, South Dakota. It provides researchers with a centralized, international patient registry for all rare diseases. This program allows patients and researchers to connect as easily as possible to help advance treatments and cures for rare diseases. The CoRDS team works with patient advocacy groups, individuals and researchers to help in the advancement of research in over 7,000 rare diseases. The registry is free for patients to enroll and researchers to access. Visit sanfordresearch.org/CoRDS to enroll.
Hypothalamic-pituitary Dysfunction in Diabetes
Diabete MellitusHypogonadism3 moreType 2 Diabetes mellitus (T2DM) is a chronic disease with a high prevalence and several comorbidities impacting on public health and society. Among the complications of T2DM it has been showed a high prevalence of hypogonadotropic hypogonadism. Even if hypogonadism is associated to a worse metabolic profile and cardiovascular risk, it is discussed whether and when to treat this potentially reversible form associated to diabetes. In fact, the pathogenic mechanism of this condition in diabetic patients is not fully understood, and its clinical correlates, including the prevalence of other possible associated hypothalamic-pituitary axes dysfunctioning, questioned. The aim of the present study is to assess with an observational, cross sectional study on a large series of type 2 diabetic patients, enrolled consecutively: all the suspected etiologies of this complication in one single evaluation (both acquired and genetic congenital predisposition), its clinical correlates and the real prevalence of the disease using the lastly validated criteria for late onset hypogonadotropic hypogonadism.
Genetics of Reproductive Disorders (Including Kallmann Syndrome) and Cleft Lip and/or Palate
Kallmann SyndromeHypogonadotropic Hypogonadism6 moreThe purpose of this study is to explore the genetic basis of reproductive disorders and cleft lip and/or palate.
Hypogonadotropic Hypogonadism in Obese Young Males
HypogonadismHypogonadotropicObesity can lead to low testosterone concentrations in young men. This study will study the effects of low testosterone in those men and the result of treating them with clomiphene.
A Phase 1/2a Study to Determine the Dose Response Pharmacokinetics of TSX-011 (Testosterone Undecanoate)...
HypogonadismHypogonadism4 moreThis will be a phase 1/2a, open-label, single-center study with 3 periods. The aims of the study are to: evaluate the dose-response curve following ascending single doses of TSX-011; confirm optimum dosing conditions; evaluate the efficacy of single or multiple daily adaptive dosing; and evaluate the safety and tolerability of TSX-011.
Effect of Testosterone on Endothelial Function and Microcirculation in Type 2 Diabetic Patients...
Type 2 DiabetesHypogonadismDiabetes mellitus is associated with long-term complications affecting mainly the eyes, nerves and kidneys. One of the main underlying causes for this is damage to the lining of the small blood vessels supplying these organs with dysfunction of the endothelium (lining of the small blood vessels). Testosterone has been shown to have an effect macro (large) blood vessels with limited data available on the micro (small) blood vessels. Testosterone is recognised to have important effects on metabolism and vascular behaviour beyond the accepted effects on secondary sexual characteristics. Physiological testosterone therapy is associated with some beneficial effects on the cardiovascular system and has been used with some success to treat patients with stable angina and chronic heart failure. The investigators therefore propose to study the effects of testosterone replacement therapy in patients with hypogonadism (low testosterone levels) on the endothelium in males with type 2 diabetes. 40 diabetic patients with type 2 diabetes and low testosterone levels and erectile dysfunction (impotence) will be recruited into the study. All patients will receive testosterone replacement therapy and 10 patients will also receive Vardenafil (a drug used to treat impotence). The investigators hope to demonstrate an improvement in endothelial dysfunction by assessing biochemical markers such as nitric oxide (a chemical that causes relaxation for the blood vessels) and C-reactive protein (a chemical that can increase in patients with diabetes) as well as the effect on weight, blood pressure, diabetes control and cholesterol.
Hypogonadism in Young Men With Type 2 Diabetes
Hypogonadotropic HypogonadismType 2 DiabetesLow testosterone production, known clinically as hypogonadism, appears to be common complication of type 2 diabetes, affecting one in three diabetic men. Hypogonadism is known to be associated with decreased muscle mass, increased fat mass, increased inflammation and decreased fertility. In this grant, the investigators propose to study the effects of having low testosterone on 1) insulin sensitivity, the ability of the body to handle glucose 2) fat and muscle mass at specific areas of the body 3) expression of mediators of inflammation in the blood 4) semen quality. This study will compare diabetic men (with or without hypogonadism). This study will also evaluate the effect of treatment with clomiphene (a drug that increases testosterone and sperm production) or testosterone in men with diabetes and hypogonadism. The investigators hope that this project will help us understand the state of hypogonadism in young type 2 diabetic men who are in their peak fertility years and give us insights into treatment of this condition. With the rising prevalence of type 2 diabetes in the young, this project may have implications for public health.