Plasticity in developmental programming has evolved in order to provide the best chances of survival and reproductive success to the organism under changing environments. Environmental conditions that are experienced in early life can profoundly influence human biology and long-term health. Developmental origins of health and disease and life-history transitions are purported to use placental, nutritional, and endocrine cues for setting long-term biological, mental, and behavioral strategies in response to local ecological and/or social conditions. The window of developmental plasticity extends from preconception to early childhood and involves epigenetic responses to environmental changes, which exert their effects during life-history phase transitions. These epigenetic responses influence development, cell- and tissue-specific gene expression, and sexual dimorphism, and, in exceptional cases, could be transmitted transgenerationally. Translational epigenetic research in child health is a reiterative process that ranges from research in the basic sciences, preclinical research, and pediatric clinical research. Identifying the epigenetic consequences of fetal programming creates potential applications in clinical practice: the development of epigenetic biomarkers for early diagnosis of disease, the ability to identify susceptible individuals at risk for adult diseases, and the development of novel preventive and curative measures that are based on diet and/or novel epigenetic drugs.
Endocrinology of Adipose Tissue-An Update ures and of specifi c drugs that may be able to restore the dysregulated endocrine system of adipose tissue. It was hoped that through prevention and intervention the deleterious sequelae of obesity and, in particular, of the visceral accumulation of body fat, might be avoided. Five years later, more than one hundred adipose tissue secretion products have been described including fatty acids, prostaglandins, and steroids, as well as complex proteins (᭹ ᭤ Fig. 1). Some of these factors primarily have local auto-or paracrine effects in adipose tissue, while others are released into the circulation and exert specifi c effects at target organs or systemic effects. In this review, we present an overview of the endocrine functions of adipose tissue with special focus on fi ndings obtained within the past 5 years. Old and new fi ndings of adipose tissue cellularity & Adipose tissue mass is determined by competing processes regulating both the volume and the number of adipocytes. For many years the dogma claimed that the number of adipocytes is fi xed during childhood, and remains constant throughout life. According to this model, changes in size of adipose tissue could only be achieved by modulation of adipocyte volume, which in turn is bal-Authors P.
Despite substantial heritability in pubertal development, much variation remains to be explained, leaving room for the influence of environmental factors to adjust its phenotypic trajectory in the service of fitness goals. Utilizing evolutionary development biology (evo-devo), we examine adolescence as an evolutionary life-history stage in its developmental context. We show that the transition from the preceding stage of juvenility entails adaptive plasticity in response to energy resources, other environmental cues, social needs of adolescence and maturation toward youth and adulthood. Using the evolutionary theory of socialization, we show that familial psychosocial stress fosters a fast life history and reproductive strategy rather than early maturation being just a risk factor for aggression and delinquency. Here we explore implications of an evolutionary-developmental-endocrinological-anthropological framework for theory building, while illuminating new directions for research.
Bone fragility in Turner's syndrome is reflected by low SOS but not by DXA BMD. Low QUS, which assesses the cortical bone only, supports a defect in cortical bone in Turner's syndrome. Lack of SOS correlation with age, height and hormonal therapy in Turner's syndrome suggests a primary bone defect, rather than enhanced resorption of endocrine origin.
In the last few decades, pediatric medicine has observed a dramatic increase in the prevalence of hitherto rare illnesses, among which obesity, diabetes, allergies and other autoimmune diseases stand out. In addition, secular trends towards earlier onset of puberty and sexual activity contribute to the psychological problems of youth and adolescents. All this has occurred in spite of the improved health care provision for children, yet traditional concepts of medicine have failed to explain these new ?epidemics?. A recent conference and science school of the European Society of Paediatric Endocrinology (ESPE) in Acre, Israel, has taken up this challenge. Experts across disciplines including medicine, anthropology and developmental psychology discussed potential causes of childhood ill-health from an evolutionary point-of-view. Seen from an evolutionary vantage point, the ?epidemics? of childhood obesity, diabetes and psychological dysfunction appear, in part, to be related to a mismatch between ancestral adaptations and novel environmental contingencies. These include changing exposures to pathogens, which impact on the function of the immune system, as well as changing patterns of parenting, which influence the timing of puberty and the risk for developing psychopathology.
Hyperlipidemia has been reported in adults with hypopituitarism, and human (h) GH therapy has been shown to lower plasma cholesterol in patients with hypercholesterolemia. Macrophage cholesterol accumulation is an early event in atherosclerosis, and these cells have been shown to respond to GH and insulin-like growth factor (IGF-I). The present study was aimed at investigating the activity of GH and IGF-I in macrophages, and used murine macrophages as a model system to investigate the effects of GH and IGF-I on cellular uptake and metabolism of low density lipoprotein (LDL). The J-774 murine macrophage cell line was shown to bind hGH, to respond to hGH by an increase in cell IGF-I content, and to have specific high affinity binding sites for IGF-I. Mouse peritoneal macrophages and the J-774 macrophage cell line respond to hGH with a dose-dependent stimulation of cellular association and degradation of LDL as well as an enhanced cholesterol esterification rate. A similar response was observed after in vitro treatment of the cells with IGF-I. Preliminary results in human monocyte-derived macrophages showed similar results. The dependency of the effect of hGH on locally produced IGF-I was shown by abrogation of the hGH effect after adding anti-IGF-I antibody to the culture medium. It is concluded that murine macrophages possess the machinery to bind GH, produce IGF-I, and bind IGF-I. This machinery is used by macrophages, and apparently by other cells, to execute GH-dependent IGF-I-mediated stimulation of cellular uptake and metabolism of LDL. This may provide the explanation for both the elevated plasma LDL concentration in patients with GH deficiency and the effect of GH therapy to reduce plasma LDL levels.
ContextThe age of puberty has fallen over the past 130 years in industrialized, western countries, and this fall is widely referred to as the secular trend for earlier puberty. The current study was undertaken to test two evolutionary theories: (a) the reproductive system maximizes the number of offspring in response to positive environmental cues in terms of energy balance, and (b) early puberty is a trade-off response for high mortality rate and reduced resource availability.MethodsUsing a sample of 22 natural-fertility societies of mostly tropical foragers, horticulturalists, and pastoralists from Africa, South America, Australia, and Southeastern Asia, this study compares indices of adolescence growth and menarche with those of fertility fitness in these non-industrial, traditional societies.ResultsThe average age at menarche correlated with the first reproduction, but did not correlate with the total fertility rate TFR or reproductive fitness. The age at menarche correlated negatively with their average adult body mass, and the average adult body weight positively correlated with reproductive fitness. Survivorship did not correlate with the age at menarche or age indices of the adolescent growth spurt. The population density correlated positively with the age at first reproduction, but not with menarche age, TFR, or reproductive fitness.ConclusionsBased on our analyses, we reject the working hypotheses that reproductive fitness is enhanced in societies with early puberty or that early menarche is an adaptive response to greater mortality risk. Whereas body mass is a measure of resources is tightly associated with fitness, the age of menarche is not.
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