Transition in Pediatric and Adolescent Hypogonadal Girls: Gynecological Aspects, Estrogen Replacement Therapy, and Contraception.
uul A Abstract Hypogonadism may be suspected if puberty is delayed. Pubertal delay may be caused by a normal physiological variant, by primary ovarian insufficiency (Turner syndrome), or reflect congenital hypogonadotropic hypogonadism (HH; genetic) or acquired HH (brain lesions). Any underlying chronic disease like inflammatory bowel disease, celiac disease, malnutrition (anorexia or orthorexia), or excessive physical activity may also result in functional HH. Thus, girls with delayed puberty should be evaluated for an underlying pathology before any treatment, including oral contraception, is initiated. Estrogen...
Source: Endocrine Development - June 14, 2018 Category: Endocrinology Authors: Tønnes Pedersen A, Cleemann L, Main KM, Juul A Tags: Endocr Dev Source Type: research

"Child-Adult" Transition - Adolescence: When Illness Appears ….
"Child-Adult" Transition - Adolescence: When Illness Appears…. Endocr Dev. 2018 Jun 08;33:10-16 Authors: Malivoir S, Gueniche K Abstract Considering the patient's transition from child to adolescent to adult and its psychological aspects in endocrinology and diabetology, it is necessary to recall the child's psycho-affective development when he enters adolescence. Indeed, adolescence appears paradigmatic of the "child-adult" transition; it is a specific and decisive psychic process which allows the child to become an adult, that is to say autonomous and subject to his desire...
Source: Endocrine Development - June 8, 2018 Category: Endocrinology Authors: Malivoir S, Gueniche K Tags: Endocr Dev Source Type: research

Growth Hormone Deficiency in the Transition Age.
Abstract Growth hormone (GH) is essential not only for normal growth during childhood, but also for the acquisition of bone mass and muscle strength in both sexes. This process is completed after the achievement of adult height in the phase of transition from adolescence to adulthood. Adolescents with childhood onset GH deficiency (GHD) show reduction of bone mineral density, decrease in lean body mass, increase in fat mass, and deterioration of the lipid profile. For this reason, continuation of GH replacement therapy in the transition age is recommended in all patients with a confirmed diagnosis of GHD. To confi...
Source: Endocrine Development - June 8, 2018 Category: Endocrinology Authors: Loche S, Di Iorgi N, Patti G, Noli S, Giaccardi M, Olivieri I, Ibba A, Maghnie M Tags: Endocr Dev Source Type: research

Fertility Preservation in Klinefelter Syndrome Patients during the Transition Period.
Abstract Spermatozoa have occasionally been identified in ejaculate of adult Klinefelter syndrome (KS) patients but very exceptionally in KS adolescents. Spermatozoa can also be retrieved in testicular tissue of KS adolescents. The testis may also harbor spermatogonia and noncompletely differentiated germ cells. Neither clinical features nor hormonal parameters could predict germ cell recovery in KS adults or adolescents. No predictive factors can actually demonstrate that early diagnosis of KS would allow increasing the chance of sperm retrieval even if it has been suggested that semen quality may decline with ag...
Source: Endocrine Development - June 8, 2018 Category: Endocrinology Authors: Rives N, Rives A, Rondanino C, Castanet M, Cuny A, Sibert L Tags: Endocr Dev Source Type: research

Transition of Care from Childhood to Adulthood: Congenital Adrenal Hyperplasia.
Abstract Deficiency of the 21-hydroxylase enzyme is the most common form of congenital adrenal hyperplasia (CAH), accounting for more than 95% of the cases. With the advent of newborn screening and hormone replacement therapy, most children with CAH survive into adulthood. Adolescents and adults with CAH experience a number of complications, including short stature, obesity, infertility, impaired bone mineral density, and reduced quality of life. Transition from pediatric to adult care and management of long-term complications are challenging for both patients and practitioners. In adulthood, the aims of the medic...
Source: Endocrine Development - June 8, 2018 Category: Endocrinology Authors: Bachelot A Tags: Endocr Dev Source Type: research

Challenges of the Transition from Pediatric Care to Care of Adults: "Say Goodbye, Say Hello".
Challenges of the Transition from Pediatric Care to Care of Adults: "Say Goodbye, Say Hello". Endocr Dev. 2018 Jun 08;33:1-9 Authors: Touraine P, Polak M Abstract Transition has been defined as "the purposeful, planned movement of adolescents and young adults with chronic physical and medical conditions from child-centered to adult-oriented health care systems." We will here describe the challenges of such a process: challenges coming from the pediatrician, from the adolescent, linked to the disease itself, and those from the parents. We will outline how to overcome those fears and...
Source: Endocrine Development - June 8, 2018 Category: Endocrinology Authors: Touraine P, Polak M Tags: Endocr Dev Source Type: research

Transitions in Care from Pediatric to Adult Health Care Providers: Ongoing Challenges and Opportunities for Young Persons with Diabetes.
Abstract Adolescence and young adulthood are times of multiple developmental changes, including physiological, social, emotional, cognitive, and behavioral transformations. The adolescent or young adult living with type 1 or type 2 diabetes must navigate the vicissitudes of these developmental stages while managing the rigors and self-care demands of these conditions. Diabetes in children is managed by adults, mainly by parents. As the child matures, diabetes management tasks transition from parents to the developing teen. This transition in care is a process that generally begins in early adolescence and culminat...
Source: Endocrine Development - June 8, 2018 Category: Endocrinology Authors: Garvey K, Laffel L Tags: Endocr Dev Source Type: research

Transition of Care from Childhood to Adulthood: Turner Syndrome.
Abstract Girls with Turner syndrome (TS) require special consideration during transition from childhood to adult care. During the transition years, treatment for short stature will be completed and sexual development induced in parallel with the peer group. The timing of sexual development may have later repercussions with respect to psychosocial development and partnership status. Late presentation of TS, which is so common, can result in additional difficulties with the transition process. PMID: 29886498 [PubMed - as supplied by publisher] (Source: Endocrine Development)
Source: Endocrine Development - June 8, 2018 Category: Endocrinology Authors: Conway G Tags: Endocr Dev Source Type: research

Fertility Preservation in Endocrine Disorders during Transition for Girls.
erg M Abstract Recent advances in fertility preservation (FP) techniques have led to a wide spread of indications. FP should now be discussed not only for young girls having to receive gonadotoxic treatments for cancer, but also for those with genetic or endocrine disorders, as well as benign ovarian diseases at risk of premature ovarian insufficiency. For premenarchal girls, ovarian tissue cryopreservation is still the only available technique. Oocyte cryopreservation after ovarian stimulation could be offered to postmenarchal girls. Whenever possible, the parents and the young patient should be informed of the b...
Source: Endocrine Development - June 8, 2018 Category: Endocrinology Authors: Bénard J, Sermondade N, Grynberg M Tags: Endocr Dev Source Type: research

Management of Hypothalamic Obesity during Transition from Childhood to Adulthood.
Abstract Hypothalamic obesity (HO) is a rare and serious disease of various origins: tumor, traumatism, radiotherapy, vascular, genetic, or even psychotropic drug use. HO usually begins in childhood with eating disorders and progresses with an aggregate of severe comorbidities. Transition from pediatric to adult health care is a critical period to assure weight stability and a good management of comorbidities. In case of loss to follow-up, there is an increased risk of major weight gain and long-term complications with severe obesity. To minimize this risk, pediatric and adult specialists must work together to pre...
Source: Endocrine Development - June 8, 2018 Category: Endocrinology Authors: Bretault M, Carette C, Barsamian C, Czernichow S Tags: Endocr Dev Source Type: research

Transition of Care from Childhood to Adulthood: Congenital Hypogonadotropic Hypogonadism.
This article will review the state of the art in diagnosis and treatment of patients with CHH with a particular focus on supporting an effective transition from pediatric-centered care to adult-oriented endocrine services. A synthesis of best practices is offered to help guide clinicians in supporting patients and families during this challenging period of care. PMID: 29886503 [PubMed - as supplied by publisher] (Source: Endocrine Development)
Source: Endocrine Development - June 8, 2018 Category: Endocrinology Authors: Dwyer AA, Pitteloud N Tags: Endocr Dev Source Type: research

Enteroendocrine Cells: Metabolic Relays between Microbes and Their Host.
Abstract Gut bacteria exert a variety of metabolic functions unavailable to the host and are increasingly seen as a virtual organ located inside our gastrointestinal tract. Scattered in our intestinal epithelium, enteroendocrine cells (EECs) regulate several aspects of the host's physiology and translate signals coming from the gut microbiota through their hormonal secretions. In this chapter, we will assess the interplay between the gut microbiota and EEC and its consequences for the physiology of the host. We will first describe alterations of different populations of EEC in germ-free animals. The role of mediat...
Source: Endocrine Development - September 13, 2017 Category: Endocrinology Authors: Plovier H, Cani PD Tags: Endocr Dev Source Type: research

The Changing Concept of Gut Endocrinology.
Abstract Gastrointestinal hormones are released from enteroendocrine cells in the digestive tract. More than 30 hormone genes are expressed, which make the gut the largest endocrine organ in the body. At present, it is feasible to conceive the hormones under 5 headings: the structural homology groups most hormones into 9 families, each of which is assumed to originate from a single gene. Today's hormone gene often has multiple phenotypes due to alternative splicing, tandem organization or differentiated maturation of the prohormone. By these mechanisms, more than 100 different hormonal peptides are released from t...
Source: Endocrine Development - September 6, 2017 Category: Endocrinology Authors: Rehfeld JF Tags: Endocr Dev Source Type: research

Development and Anatomy of the Enteroendocrine System in Humans.
Abstract The gastrointestinal (GI) tract exhibits an enormous surface area that consists mostly of absorptive enterocytes. Enteroendocrine cells (EECs) are found scattered along the GI tract between absorptive enterocytes and other secretory cells, and comprise around 1% of the epithelial cell population. Interestingly, they develop from the same crypt stem cell as the other absorptive or secretory cells of the gut. EECs differentiate along the crypt villus axis and are renewed every 4-6 days, and hence possess a high plasticity. They constitute the largest endocrine system in the human body by secreting multiple ...
Source: Endocrine Development - September 6, 2017 Category: Endocrinology Authors: Posovszky C Tags: Endocr Dev Source Type: research

Incretins and Their Endocrine and Metabolic Functions.
Abstract Incretins are hormones secreted into the blood stream from the gut mucosa in response to nutrient intake. They have been characterized based on their capacity to lower blood glucose levels. The more potent reduction of blood glucose coupled to a more intensive stimulation of insulin secretion, in response to oral glucose uptake, as compared to intravenous glucose infusion has further been termed the "incretin effect." As a prototype incretin hormone, the biology of glucagon-like peptide 1 (GLP-1) has been intensively studied. GLP-1 actions are mediated through cyclic adenosine monophosphate-coup...
Source: Endocrine Development - September 6, 2017 Category: Endocrinology Authors: Seufert J Tags: Endocr Dev Source Type: research

Role of Incretin Hormones in Bowel Diseases.
Abstract Enteroendocrine cells (EEC) have been studied extensively for their ability to regulate gastrointestinal motility and insulin release by secretion of peptide hormones. In particular, the L cell-derived incretin glucagon-like peptide 1 has gained enormous attention due to its insulinotropic action and relevance in the treatment of type 2 diabetes. Yet, accumulating data indicates a critical role for EEC and incretins in metabolic adaptation and in orchestrating immune responses beyond blood glucose control. EEC actively sense the lamina propria and luminal environment including the microbiota via receptors...
Source: Endocrine Development - September 6, 2017 Category: Endocrinology Authors: Zietek T, Waldschmitt N, Rath E Tags: Endocr Dev Source Type: research

Ghrelin and Growth.
Abstract Ghrelin is a pleiotropic hormone, whose effect on growth hormone secretion, through the growth hormone secretagogue (GHS) receptor, is one of its many actions. Relationships between GHS receptor gene variants and human height, both in healthy individuals and in patients with growth disorders have been identified. These include constitutional delay in growth and puberty, idiopathic short stature, and isolated growth hormone deficiency. In this review, we provide an overview of the role of ghrelin in growth. PMID: 28873385 [PubMed - in process] (Source: Endocrine Development)
Source: Endocrine Development - September 6, 2017 Category: Endocrinology Authors: Perchard R, Clayton PE Tags: Endocr Dev Source Type: research

Development of Sweet Taste Perception: Implications for Artificial Sweetener Use.
Abstract Humans have an innate liking for sweetness, which may have an evolutionary basis. Sweetness typically signals the presence of calories and nutrients and thus, universal liking for sweet taste once served to support survival. In the modern food supply, however, sweetness is often delivered via added sugars and sweeteners devoid of other beneficial nutrients. Nonnutritive sweeteners (NNS) provide sweetness with no or few calories, and therefore may offer a potential strategy to maintain food and beverage palatability, while reducing the caloric content. Despite marked increases in NNS use, their metabolic a...
Source: Endocrine Development - September 6, 2017 Category: Endocrinology Authors: Sylvetsky AC, Conway EM, Malhotra S, Rother KI Tags: Endocr Dev Source Type: research

Just a Gut Feeling: Central Nervous Effects of Peripheral Gastrointestinal Hormones.
Abstract Despite greater health education, obesity remains one of the greatest health challenges currently facing the world. The prevalence of obesity among children and adolescents and the rising rates of prediabetes and diabetes are of particular concern. A deep understanding of regulatory pathways and development of new anti-obesity drugs with increased efficacy and safety are of utmost necessity. The 2 major biological players in the regulation of food intake are the gut and the brain as peptides released from the gut in response to meals convey information about the energy needs to brain centers of energy hom...
Source: Endocrine Development - September 6, 2017 Category: Endocrinology Authors: Roth CL, Doyle RP Tags: Endocr Dev Source Type: research

Gastrointestinal Endocrinology in Bariatric Surgery.
Abstract The long-lasting weight-reducing effect of bariatric surgical procedures cannot simply be explained by the malabsorption of nutrients and the subsequent energy deficit due to this malabsorption. Clinical studies have shown that the reorganization of the anatomy of the gut and the subsequent alterations of gastrointestinal physiology have a large impact on the secretion and function of gastrointestinal hormones, which regulate hunger and satiety. These changes have been named the BRAVE effect: bile flow alteration, reduction of gastric size, anatomical gut rearrangement and altered flow of nutrients, vagal...
Source: Endocrine Development - September 6, 2017 Category: Endocrinology Authors: Wabitsch M Tags: Endocr Dev Source Type: research

Treatment of Diabetes and Obesity by Rationally Designed Peptide Agonists Functioning at Multiple Metabolic Receptors.
i R Abstract Obesity and its comorbidities such as type 2 diabetes constitute major worldwide health threats, and the identification of an effective medical intervention has emerged as a global priority. The limited effectiveness of historical, anti-obesity treatments is commonly attributed to the complexity of the disease and the redundancy of metabolic regulatory mechanisms that sustain body weight. At the forefront of obesity research is the development of combinational drug therapies that simultaneously target multiple regulatory pathways, which promote dysfunctional metabolism. Recently, molecularly crafted u...
Source: Endocrine Development - September 6, 2017 Category: Endocrinology Authors: Khajavi N, Biebermann H, Tschöp M, DiMarchi R Tags: Endocr Dev Source Type: research

Gastrointestinal Hormones Induced the Birth of Endocrinology.
Abstract The physiological studies by British physiologists William Maddock Bayliss and Ernest Henry Starling, at the beginning of the last century, demonstrated the existence of specific messenger molecules (hormones) circulating in the blood that regulate the organ function and physiological mechanisms. These findings led to the concept of endocrinology. The first 2 hormones were secretin, discovered in 1902, and gastrin, discovered in 1905. Both hormones that have been described are produced in the gut. This chapter summarizes the history around the discovery of these 2 hormones, which is perceived as the birth...
Source: Endocrine Development - September 6, 2017 Category: Endocrinology Authors: Wabitsch M Tags: Endocr Dev Source Type: research

Gestational Diabetes Mellitus.
Abstract Based on the Hyperglycemia and Adverse Pregnancy Outcome study, new universal screening recommendations and cut-offs for gestational diabetes mellitus (GDM) have been proposed. In addition to the immediate perinatal risk, GDM carries an increased risk of metabolic disease in the mother and child. Maternal obesity has even been shown to be associated with increased all-cause mortality in offspring. In addition to known risk factors, excessive gestational weight gain, increased fat consumption, a low vitamin D level, psychological stress and negative mood are risk factors for GDM. Regarding therapy, the US ...
Source: Endocrine Development - January 30, 2016 Category: Endocrinology Authors: Spaight C, Gross J, Horsch A, Puder JJ Tags: Endocr Dev Source Type: research

The 'Old' Anti-Diabetic Agents: A Systematic Inventory.
z M Abstract An array of oral agents is available for the treatment of hyperglycaemia in type 2 diabetes. This systematic inventory focuses on 'old' oral agents, including metformin, sulfonylureas (SUs), thiazolidinediones, alpha glucosidase inhibitors, and meglitinides. Twelve meta-analyses and six randomized controlled trials that used patient-relevant outcomes as primary endpoints were critically reviewed. Guidelines recommend the use of metformin or an SU as the first-line pharmacotherapeutic options. Beneficial effects of metformin have been demonstrated for 'any diabetes-related endpoint' and 'all-cause mort...
Source: Endocrine Development - January 30, 2016 Category: Endocrinology Authors: Buhse S, Mühlhauser I, Lenz M Tags: Endocr Dev Source Type: research

Novel Therapeutic Approaches in Diabetes.
Abstract This chapter deals with novel therapeutic approaches, predominantly for type 2 diabetes. Incretin-based therapies utilize the effects of glucagon-like peptide-1 (GLP-1), which stimulates insulin and inhibits glucagon secretion in a glucose-dependent manner. Incretin-based therapies comprise injectable GLP-1 receptor agonists and orally active dipeptidyl peptidase-IV inhibitors. Both have a low hypoglycaemia risk. GLP-1 receptor agonists (exenatide, liraglutide, lixisenatide, dulaglutide, albiglutide) reduce glycated haemoglobin levels more effectively than oral antidiabetic agents do and lead to weight lo...
Source: Endocrine Development - January 30, 2016 Category: Endocrinology Authors: Gallwitz B Tags: Endocr Dev Source Type: research

Genetic Defects of the β-Cell That Cause Diabetes.
Genetic Defects of the β-Cell That Cause Diabetes. Endocr Dev. 2016;31:179-202 Authors: Stekelenburg CM, Schwitzgebel VM Abstract Individuals with higher-than-normal blood sugar levels used to be diagnosed as having either type 1 or type 2 diabetes. We now know that a wide range of different factors can cause diabetes, including single gene defects, which account for at least 1% of all diabetes cases and up to 4% of cases in the pediatric population. However, misdiagnosis remains common due to the considerable clinical overlap between the different diabetes forms. Monogenic diabetes onset can occ...
Source: Endocrine Development - January 30, 2016 Category: Endocrinology Authors: Stekelenburg CM, Schwitzgebel VM Tags: Endocr Dev Source Type: research

Diabetes Technology.
r A Abstract Diabetes technology is an evolving field. The research started with the development of blood glucose meters for patient self-testing and the introduction of insulin pen injection devices. Modern devices employ new technological features, such as the use of computer simulations and mathematical algorithms, connectivity and signal transfer, and the use of modern (space research-derived) materials. With these innovations, the goal to develop an artificial pancreas by closing the loop between a continuous glucose sensor and a continuous insulin-delivering device via insulin delivery algorithms is coming c...
Source: Endocrine Development - January 30, 2016 Category: Endocrinology Authors: Pfützner A Tags: Endocr Dev Source Type: research

Genetics of Type 2 Diabetes.
A, Laakso M Abstract Genetic and environmental factors as well as their interactions contribute to the pathogenesis of type 2 diabetes. Linkage analysis, candidate gene approaches, genome-wide association studies, and sequencing have been used in the identification of common, low-frequency and rare variants for type 2 diabetes. Genome-wide association studies have identified>80 common variants for type 2 diabetes, with small effect sizes (risk of type 2 diabetes increased by 5-40%). Almost all of these variants regulate insulin secretion, and only a few regulate insulin sensitivity. Common variants capture only...
Source: Endocrine Development - January 30, 2016 Category: Endocrinology Authors: Stančáková A, Laakso M Tags: Endocr Dev Source Type: research

Novelties in Diabetic Retinopathy.
Abstract Although diabetic retinopathy (DR) remains a leading cause of vision loss, the last decade has brought significant advances in the diagnosis and treatment of this common complication of diabetes mellitus. First, optical coherence tomography allows for noninvasive imaging of the retina, in particular, the macula, with very high resolution, thus facilitating the management of diabetic macular edema. In addition, recent advances in the understanding of the pathophysiology of DR, in particular, the key role of cytokines, such as vascular endothelial growth factor (VEGF), have led to the development of anti-VE...
Source: Endocrine Development - January 30, 2016 Category: Endocrinology Authors: Ebneter A, Zinkernagel MS Tags: Endocr Dev Source Type: research

Hypertension and Diabetic Nephropathy.
Abstract Diabetic nephropathy (DN) is a major complication of both type 1 and type 2 diabetes. DN is the most common cause of end-stage renal disease, and it markedly enhances the risk of cardiovascular events. An elevated urinary albumin excretion rate, increased blood pressure (BP), and a continual loss of renal function are characteristics of DN. Screening for microalbuminuria is central to diabetes care, and antihypertensive agents are used for the primary prevention and treatment of DN. Angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers play central roles and have protective propert...
Source: Endocrine Development - January 30, 2016 Category: Endocrinology Authors: Skov J, Christiansen JS, Poulsen PL Tags: Endocr Dev Source Type: research

The Diabetic Foot: The Never-Ending Challenge.
Abstract Diabetes, a major public health concern, is increasing in prevalence worldwide. A diabetic patient has an up to 25% lifetime risk of developing a foot ulcer condition that predisposes that patient to lower-extremity amputation. The underlying pathology is diabetic peripheral neuropathy and peripheral arterial disease (PAD) associated with deformities of foot anatomy due to motor neuropathy. Trauma, often secondary to ill-fitting shoes, precipitates skin breakdown, whereas PAD determines the prognosis for healing. Whenever optimal offloading is guaranteed, a neuropathic ulcer will heal, whereas an ulcerati...
Source: Endocrine Development - January 30, 2016 Category: Endocrinology Authors: Peter-Riesch B Tags: Endocr Dev Source Type: research

Diabetes and Cancer.
Abstract Diabetes and cancer are common conditions, affecting 384 million and 33 million people worldwide, respectively. Therefore, there is great potential for overlap, with people with diabetes also developing cancer and vice versa. However, people with diabetes may be at increased risk of developing cancer when compared with the general population. This is due to both shared risk factors associated with the two diseases and the metabolic derangements associated with diabetes, such as hyperglycaemia, insulin resistance, hyperinsulinaemia and oxidative stress. Glucose-lowering therapies may influence the risk of ...
Source: Endocrine Development - January 30, 2016 Category: Endocrinology Authors: Holden SE Tags: Endocr Dev Source Type: research

Treatment Goals in Diabetes.
Abstract The quality of glycaemic control in diabetes mellitus relies on accurate individualization of available treatment options. Treatment targets depend on the type and duration of diabetes, the patients' abilities and characteristics and the individual risk for acute and/or late-stage complications. These complications include hypoglycaemia, which can be severe and life threatening, hyperglycaemia, which is a main factor for the development of cardiovascular disease, and macrovascular and microvascular disease, both of which are hallmark features of diabetes-associated constraints. Moreover, other treatment g...
Source: Endocrine Development - January 30, 2016 Category: Endocrinology Authors: Melmer A, Laimer M Tags: Endocr Dev Source Type: research

Beta-Cell Replacement: Pancreas and Islet Cell Transplantation.
ney T Abstract Pancreas and islet transplantation are 2 types of beta-cell replacement therapies for type 1 diabetes mellitus. Since 1966, when pancreas transplantation was first performed, it has evolved to become a highly efficient procedure with high success rates, thanks to advances in surgical technique and immunosuppression. Pancreas transplantation is mostly performed as simultaneous pancreas-kidney transplantation in patients with end-stage nephropathy secondary to diabetes. In spite of its efficiency, pancreas transplantation is still a major surgical procedure burdened by high morbidity, which called for...
Source: Endocrine Development - January 30, 2016 Category: Endocrinology Authors: Niclauss N, Meier R, Bédat B, Berishvili E, Berney T Tags: Endocr Dev Source Type: research

The Emerging Role of Epigenetics in the Regulation of Female Puberty.
Abstract In recent years the pace of discovering the molecular and genetic underpinnings of the pubertal process has accelerated considerably. Genes required for human puberty to occur have been identified and evidence has been provided suggesting that the initiation of puberty requires coordinated changes in the output of a multiplicity of genes organized into functional networks. Recent evidence suggests that a dual mechanism of epigenetic regulation affecting the transcriptional activity of neurons involved in stimulating gonadotropin-releasing hormone release plays a fundamental role in the timing of puberty. ...
Source: Endocrine Development - December 21, 2015 Category: Endocrinology Authors: Lomniczi A, Ojeda SR Tags: Endocr Dev Source Type: research

Normal Variation in Pubertal Timing: Genetic Determinants in Relation to Growth and Adiposity.
Abstract In humans, there is a considerable variation in age of onset of puberty. Twin studies have indicated that pubertal timing is a highly heritable trait. Recently, a few rare genetic causes of precocious puberty have been reported as well as genetic mutations associated with isolated hypogonadotropic hypogonadism. Genome-wide association (GWA) studies have helped to explore the genetic determinants of the normal variation in pubertal timing, but have been able to explain only 2.7% of the variance in age at menarche, highlighting the involvement of multiple genes with small effect sizes. These studies indicat...
Source: Endocrine Development - December 21, 2015 Category: Endocrinology Authors: Willemsen RH, Dunger DB Tags: Endocr Dev Source Type: research

Genetics of Hypogonadotropic Hypogonadism.
Abstract Hypogonadotropic hypogonadism (HH) often manifests as pubertal delay. A considerable proportion of cases of HH is due to genetic mutations. Recognizing those mutated genes and associated phenotypes may improve our diagnostic capabilities. GNRHR and TACR3 should be the first two genes to be screened in a clinical setting for equivocal cases such as constitutional delay in puberty versus idiopathic HH. In Kallmann syndrome (KS), according to the presence of certain accompanying clinical features, genetic screening for particular gene(s) may be prioritized: synkinesia (KAL1), dental agenesis (FGF8/FGFR1), bo...
Source: Endocrine Development - December 21, 2015 Category: Endocrinology Authors: Topaloglu AK, Kotan LD Tags: Endocr Dev Source Type: research

Sexual Precocity - Genetic Bases of Central Precocious Puberty and Autonomous Gonadal Activation.
Abstract Precocious puberty has been classically defined as the onset of sexual secondary characteristics in girls younger than 8 years and in boys younger than 9 years. The discovery of potential factors which trigger human puberty is one of the central mysteries of reproductive biology. Several approaches, including mutational analysis of candidate genes, large-scale genome-wide association studies, and (more recently) whole-exome sequencing, have been performed in attempt to identify novel genetic factors that modulate the human hypothalamic-pituitary-gonadal axis, resulting in premature sexual development. In ...
Source: Endocrine Development - December 21, 2015 Category: Endocrinology Authors: Macedo DB, Silveira LF, Bessa DS, Brito VN, Latronico AC Tags: Endocr Dev Source Type: research

Congenital Hypogonadotropic Hypogonadism: A Trait Shared by Several Complex Neurodevelopmental Disorders.
ger J Abstract Reproductive function depends on the activity of the gonadotropic axis, which is controlled by a hypothalamic neural network whose main function is to regulate the secretion of gonadotropin-releasing hormone (GnRH). This endocrine network is not mature at birth, and several phases of activation-inactivation of the gonadotropic axis are necessary for its normal development. The postnatal maturation of the GnRH network lies under the control of a neurodevelopmental program that starts in fetal life and ends at puberty. There are many clinical situations in which this program is interrupted, leading to...
Source: Endocrine Development - December 21, 2015 Category: Endocrinology Authors: de Roux N, Carel JC, Léger J Tags: Endocr Dev Source Type: research

Animal Modeling of Early Programming and Disruption of Pubertal Maturation.
Abstract Puberty is a fascinating developmental transition that gates the attainment of reproductive capacity and culminates the somatic and sexual maturation of the organism. Rather than a circumscribed phenomenon, puberty is the endpoint of a long-lasting developmental continuum, which initiates in utero. Besides important genetic determinants, the tempo of puberty is influenced by numerous endogenous and exogenous factors that, acting at different levels of the developing hypothalamic-pituitary-gonadal (HPG) axis along the maturational continuum indicated above, can influence puberty onset. Among the different ...
Source: Endocrine Development - December 21, 2015 Category: Endocrinology Authors: Castellano JM, Tena-Sempere M Tags: Endocr Dev Source Type: research

Contemporary Trends in Onset and Completion of Puberty, Gain in Height and Adiposity.
Abstract Recent studies have documented earlier pubertal maturation in both girls and boys. Several factors have been proposed to account for earlier maturation. Epidemiologic studies have indicated that genetic factors are the most important influence contributing to the variability in the onset of puberty. Studies have also noted the association of elevated BMI with earlier puberty in girls, although the relationship between BMI and onset of puberty in boys is less consistent. The relationship of BMI and onset of puberty may be mediated by several factors, including leptin and kisspeptin, changes in bioavailable...
Source: Endocrine Development - December 21, 2015 Category: Endocrinology Authors: Biro FM, Kiess W Tags: Endocr Dev Source Type: research

Consequences of Early Life Programing by Genetic and Environmental Influences: A Synthesis Regarding Pubertal Timing.
Abstract Sexual maturation is closely tied to growth and body weight gain, suggesting that regulative metabolic pathways are shared between somatic and pubertal development. The pre- and postnatal environment affects both growth and pubertal development, indicating that common pathways are affected by the environment. Intrauterine and early infantile developmental phases are characterized by high plasticity and thereby susceptibility to factors that affect metabolic function as well as related reproductive function throughout life. In children born small for gestational age, poor nutritional conditions during gest...
Source: Endocrine Development - December 21, 2015 Category: Endocrinology Authors: Roth CL, DiVall S Tags: Endocr Dev Source Type: research

Nutritional and Pubertal Disorders.
nte J Abstract Caloric-protein malnutrition can slow growth and cause pubertal delay. This chapter focuses on endocrine abnormalities and pubertal alterations in patients with eating disorders, childhood obesity, the female athlete triad and children cancer survivors. Patients with anorexia nervosa (AN) exhibit multiple endocrine abnormalities, including isolated hypogonadotropic hypogonadism. The delay in pubertal development and reduction in growth seen in AN patients may be a direct result of malnutrition. Appropriate psychiatric, nutritional and hormonal therapy is necessary. It is suggested that obesity durin...
Source: Endocrine Development - December 21, 2015 Category: Endocrinology Authors: Muñoz-Calvo MT, Argente J Tags: Endocr Dev Source Type: research

Current Changes in Pubertal Timing: Revised Vision in Relation with Environmental Factors Including Endocrine Disruptors.
Abstract The aim of this chapter is to revise some common views on changes in pubertal timing. This revision is based on recent epidemiological findings on the clinical indicators of pubertal timing and data on environmental factor effects and underlying mechanisms. A current advancement in timing of female puberty is usually emphasized. It appears, however, that timing is also changing in males. Moreover, the changes are towards earliness for initial pubertal stages and towards lateness for final stages in both sexes. Such observations indicate the complexity of environmental influences on pubertal timing. The me...
Source: Endocrine Development - December 21, 2015 Category: Endocrinology Authors: Parent AS, Franssen D, Fudvoye J, Pinson A, Bourguignon JP Tags: Endocr Dev Source Type: research

Sex Steroid and Gonadotropin Treatment in Male Delayed Puberty.
Abstract Male delayed puberty is common, affecting up to 3% of the population. Management of patients with pubertal delay is dependent on the underlying cause. The main differential diagnoses of delayed puberty in males include constitutional delay of growth and puberty (CDGP), idiopathic hypogonadotropic hypogonadism and hypergonadotropic hypogonadism. Treatment of isolated CDGP involves expectant observation or short courses of low-dose sex steroid supplementation. More complex and involved management is required in males with hypogonadism to achieve both development of secondary sexual characteristics and to ma...
Source: Endocrine Development - December 21, 2015 Category: Endocrinology Authors: Howard S, Dunkel L Tags: Endocr Dev Source Type: research

Sex Steroid Replacement Therapy in Female Hypogonadism from Childhood to Young Adulthood.
m B Abstract The overall goal of pubertal sex hormone replacement therapy (HRT) in girls is not only about development of secondary sexual characteristics, but also to establish an adult endocrine and metabolic milieu, as well as adult cognitive function. Estradiol (E2) is the first choice for HRT compared to ethinyl estradiol (EE2). E2 is the most potent endogenous estrogen in the circulation, with established levels during spontaneous puberty. Transdermal E2, compared to oral administration, is the first choice to start pubertal HRT. Transdermal application avoids liver exposure to supraphysiologic estrogen conc...
Source: Endocrine Development - December 21, 2015 Category: Endocrinology Authors: Norjavaara E, Ankarberg-Lindgren C, Kriström B Tags: Endocr Dev Source Type: research

Gonadotropin-Releasing Hormone Agonist Treatment in Sexual Precocity.
Abstract Depot gonadotropin-releasing hormone (GnRH) analogs represent the first-line therapy in sexual precocity due to central precocious puberty. GnRH analogs desensitize the pituitary and account for the suppression of luteinizing hormone and follicle-stimulating hormone leading to a decrease of sex steroid levels. The conventional indications are central puberty starting before the age of 8 years in girls and 9 years in boys. These indications can be extended to difficult conditions with poor adult height prognosis or marked psychosocial impact. This includes children after irradiation, international adoption...
Source: Endocrine Development - December 21, 2015 Category: Endocrinology Authors: Pienkowski C, Tauber M Tags: Endocr Dev Source Type: research

Treatment of Peripheral Precocious Puberty.
Abstract There are many etiologies of peripheral precocious puberty (PPP) with diverse manifestations resulting from exposure to androgens, estrogens, or both. The clinical presentation depends on the underlying process and may be acute or gradual. The primary goals of therapy are to halt pubertal development and restore sex steroids to prepubertal values. Attenuation of linear growth velocity and rate of skeletal maturation in order to maximize height potential are additional considerations for many patients. McCune-Albright syndrome (MAS) and familial male-limited precocious puberty (FMPP) represent rare causes ...
Source: Endocrine Development - December 21, 2015 Category: Endocrinology Authors: Schoelwer M, Eugster EA Tags: Endocr Dev Source Type: research

Consultation for Disordered Puberty: What Do Adolescent Medicine Patients Teach Us?
Abstract The period of adolescence is not only marked by important growth and pubertal events, but is also characterized by important psychosocial changes driven by a search for autonomy and the construction of one's identity. It can thus be easily understood that puberty disorders interfere heavily with these process, requiring from the endocrinologist not only medical knowledge, but also a great deal of emotional and psychological skills. They must progressively move from an educational approach that heavily involves the parents to one of shared information and decision making that places the young patient at th...
Source: Endocrine Development - December 21, 2015 Category: Endocrinology Authors: Michaud PA, Ambresin AE Tags: Endocr Dev Source Type: research

Toward Automation of Insulin Delivery - Management Solutions for Type 1 Diabetes.
Abstract In the past decade, the field of type 1 diabetes was characterized by the efforts to integrate technology into the daily management of diabetes. Automated insulin delivery systems have emerged followed by the improvements in technology of pumps and sensors and automated close-loop systems that were developed around the world for overnight as well as for day and night use. Initially, these closed-loop systems were tested clinically in research centers, then at diabetes camps or hotels, and recently at patients' homes. The systems were tested in a wide range of populations of patients with type 1 diabetes: ...
Source: Endocrine Development - December 21, 2015 Category: Endocrinology Authors: Nimri R, Phillip M Tags: Endocr Dev Source Type: research