Madhusmita Misra

..To do this, it is necessary to understand the mechanisms underlying low bone density in anorexia nervosa. This article discusses current concepts related to bone loss associated with anorexia nervosa, including how to prevent it...

..OPG values correlate negatively with markers of nutritional status and lumbar bone density z-scores and may be a compensatory response to the bone loss seen in this population...

..Adolescence is a common time for the onset of anorexia nervosa (AN), a condition associated with long-term medical and hormonal consequences...

..This remaining growth potential may be impaired as a consequence of low levels of insulin-like growth factor-I (IGF-I) levels from persistent undernutrition...

..Recent data suggest that marrow fat measured by 1H-magnetic resonance spectroscopy (MRS) in combination with bone mineral density (BMD) may be more valuable than either parameter alone in detecting bone weakness...

..This advantage is lost in AAs, who do not differ from nonathletes for most parameters and fare worse than EAs for cross-sectional area...

..MDD has recently been associated with lower bone mineral density (BMD) in adults. Our objective was to determine whether MDD is associated with BMD, bone turnover markers, vitamin D, and gonadal steroids in adolescents...

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..These cases suggest the need for a low threshold to undertake hormonal evaluation of patients who present with a past history of growth attenuation...

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..We hypothesized that in AN, growth hormone (GH) resistance and hypercortisolemia would increase CV risk through effects on pro-inflammatory cytokines and lipid status despite low weight...

..Adolescents with anorexia nervosa (AN) have low bone mineral density (BMD). Adipokines and insulin play an important role in bone metabolism in healthy individuals. However, their association with bone metabolism in AN is unknown...

..Our data indicate that lower peak GH and higher UFC in overweight girls are associated with visceral adiposity, insulin resistance, and lipids...

..Although primarily a disease in females, AN is increasingly being recognized in males. However, there are few or no data regarding BMD, bone turnover markers or their predictors in adolescent AN boys...

..Adult data cannot be extrapolated to children given the pubertal increase in GH concentration. In addition, because GH levels are higher in pubertal girls than boys, nadir GH may differ across gender...

..We hypothesized that baseline levels of nutritionally regulated hormones and of bone turnover markers would predict DeltaBMD overall...

..We hypothesized that menstrual recovery and weight gain (> or =10% increase in body mass index) would predict an increase in these measures of bone density...

..Baseline cortisol level strongly predicted increases in the percentage of body fat. We demonstrate that 1) high baseline cortisol level predicts increases in body fat and 2) increases in body fat predict menses recovery in AN...

..However, the effect of low testosterone and other hormonal alterations on body composition in boys with AN is not known...

..Changes in anorexigenic and orexigenic hormones in obese vs. normal-weight adolescents following high-carbohydrate and high-fat meals may influence hunger and satiety signals and subsequent food intake...

..This review discusses causes of impaired bone health in anorexia nervosa and potential therapeutic strategies...

..It is concluded that physiologic estradiol replacement increases spine and hip BMD in girls with AN...

..Bisphosphonates act by decreasing bone resorption, and are not optimal for use in adolescents with AN, in whom the primary defect is low bone formation...

..In addition, the review discusses low bone mineral density and altered bone microarchitecture in AN, the pathophysiology underlying impaired bone metabolism, and possible therapeutic strategies to optimize bone health...

..abstract:..

..Weight gain is associated with a stabilization of bone density, although residual deficits persist in the short term, and in some cases, long term...

..Although IGF-1 is key to pubertal bone accretion, and effects have been demonstrated in adults, there are no data regarding the effect of recombinant human (rh) IGF-1 administration in adolescents with AN...

..Beneficial effects of increased mechanical loading from athletic activity do not appear to protect against the deleterious effects of hypogonadism in adolescent athletes...

..The effects of supraphysiological recombinant human GH (rhGH) on GH resistance in AN are not currently known...

..Leptin predicts GH and cortisol parameters and with ghrelin predicts GH burst frequency. Low leptin and high ghrelin may be dual stimuli for high GH concentrations in undernutrition...

..We conclude that higher ghrelin and lower leptin secretion in AA related to lower fat mass may contribute to altered LH pulsatility and amenorrhea...

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..Anorexia nervosa (AN) in adolescents is associated with low bone mineral density (BMD) and increases in ghrelin secretion, an orexigenic GH secretagogue that stimulates osteoblast proliferation in vitro...

..We therefore investigated oxytocin secretion and its association with bone microarchitecture and strength in young female athletes...

..The relationship between sclerostin and bone turnover markers is disrupted in adolescent girls with AN. Despite an increase in BMD with estradiol administration in AN, estrogen does not impact sclerostin levels in this group...

..In addition, known regulators of bone turnover, such as GH, cortisol, and estrogen, explain only a fraction of the variability in bone turnover marker levels...

..Resumption of menses is associated with significant increases in the FLI, suggesting that free leptin may be an important determinant of menstrual recovery...

..Conclusion: VAT is an independent inverse determinant of bone density in obesity. This association may be mediated by adipokines and a chronic inflammatory state...

..This is particularly so for adolescents, who are in the process of accruing peak bone mass, and in whom a failure to attain peak bone mass may occur in AN in addition to loss of established bone...

..The role of other nutritionally regulated hormones such as peptide YY (PYY) and adiponectin in mediating gonadal status and bone metabolism remains to be determined...

..We investigated the relationship between leptin and ghrelin levels and symptoms of depression, anxiety and perceived stress in women across the weight spectrum...

..We therefore studied the relationship between orexigenic and anorexigenic hormones and disordered eating psychopathology in women across a range of weights...

..We hypothesized that adolescent athletes with amenorrhea (AA) would have higher ghrelin and lower leptin levels than eumenorrheic athletes (EA) and would predict levels of gonadal steroids...

..Finite element analysis (FEA) is a unique tool to estimate bone strength in vivo, and the contribution of cortical microstructure to bone strength in young athletes is not well understood...

..Moreover, oral estrogens, known to increase hsCRP in other populations, are commonly prescribed in AN. To date, hsCRP levels and their physiological determinants have not been reported in women with AN...

..In a transgenic mouse model, FGF-21 reduces IGF-I levels by inhibiting signal transducer and activator of transcription-5, a mediator of the intracellular effects of GH...

..Adipocytes and osteoblasts differentiate from a common progenitor cell, the human mesenchymal stem cell. Therefore, understanding factors that regulate this differentiation process may provide insight into bone loss in AN...

..Significant hypercortisolemia, as in Cushing's disease, causes bone loss. It is unknown whether anxiety and depression and/or cortisol dysregulation contribute to low bone density in AN or HA...

..Therefore, high cortisol values in AN may contribute to the low bone density observed in adolescents with this disorder by decreasing bone formation...

..Puberty is characterized by increases in growth hormone (GH) and insulin-like growth factor-1 (IGF-1) and the pubertal growth spurt. Bone formation and resorption also increase, consistent with increased bone metabolism...

..Estrogen administration has not been shown to prevent bone loss in this population, and to date, there are no approved, effective therapies for this comorbidity...

..Further studies are needed to define GH suppression in an adolescent population...

..Abnormal bone microarchitecture is an independent determinant of fracture risk and has not been assessed in young athletes and nonathletes...

..Y2 receptor knockout mice have increased bone mineral density (BMD) and thus PYY may play a role in regulating bone mass. We hypothesized that PYY levels would be inversely associated with BMD in women with AN...

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..78, P<0.0001). Less robust correlations were observed for calcium intake (r=0.65, P<0.0001). The FFQ used in this study can be effectively used to assess daily calcium and vitamin D intake in adolescent girls with anorexia nervosa...

..High cortisol levels in AN predict a redistribution of lean body mass such that extremity lean mass decreases. Further studies are necessary to better understand the implications of these data...

..In contrast with previous findings in adults, this most likely represents normalization of fat distribution rather than development of truncal adiposity...

..Our objective was to investigate the relationship between oxytocin levels, bone mineral density, and body composition in women with anorexia nervosa...

..Anorexia nervosa (AN) is complicated by severe bone loss. The effects of persistent undernutrition and consequent neuroendocrine dysfunction on bone mass and the factors influencing skeletal recovery have not been well characterized...

..Obesity is associated with decreased spontaneous and stimulated GH secretion, but the effect of body mass index (BMI) on results of GH stimulation testing in children with short stature is not known...

..The most important predictor of ghrelin concentration is insulin resistance, and ghrelin in turn predicts GH and cortisol burst frequency...

..The level of hydration does not significantly affect most DXA body composition measurements, with the exceptions of thigh fat...

..Peptide YY (PYY) is an anorexigenic hormone that is high in anorexia nervosa and low in obesity, inhibits GnRH secretion, and is suppressed by GH administration. The relationship between PYY and GH has not been examined across puberty...

..We concluded that bone microarchitecture is abnormal in women with AN. Endogenous IGF-I, leptin, and androgen levels predict bone microarchitecture independent of BMI...

..Acquired GH resistance may play a role in the osteopenia and decreased peak bone mass frequently associated with AN...

..A better understanding of pathways linking low energy availability with functional hypothalamic amenorrhea and low BMD is critical for the development of future therapeutic strategies addressing these issues in amenorrheic athletes...

..In addition, growth hormone may have direct effects on the growth plate independent of insulin-like growth factor 1 to increase statural growth...

..Because androgens are known to affect mood and behavior, we hypothesized that low endogenous androgen production in anorexia nervosa would predict anxiety and depression severity...

..Peptide hormones, including amylin, GIP, and GLP2, are released immediately after nutrient intake and may be involved in the regulation of bone turnover...

..A value within the normal female range in a virilized patient did not exclude dysgenetic testicular tissue or ovotestis, whereas undetectable values were consistent with the absence of testicular tissue...

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..To describe a patient with corticotropin-independent Cushing syndrome previously diagnosed and treated as congenital adrenal hyperplasia (CAH)...

..Examines the effects of bariatric surgery on adolescent obesity...

..This review describes recent insights into the pathophysiology and treatment of polycystic ovary syndrome, with special attention given to the relationship between polycystic ovary syndrome and obesity...

..We conclude that preoperative measurement of MIS facilitates the management of children with cryptorchidism and intersex disorders and offers a measure of Sertoli cell function...

..We hypothesized that children with GH deficiency (GHD) and greatest severity of GHD would be most likely to develop central hypothyroidism and decreased growth velocity (GV)...

..We also review data regarding who should receive GHRT, the criteria for diagnosing persistent GHD, dosing of GHRT and the possibility of a GH 'holiday'...

..Evidence Acquisition: We used the Entrez-PubMed search engine to conduct a review of publications addressing IGF-I deficiency, the use of rhIGF-I, and treatment for short stature...

..In this report, we summarize the published data regarding the use of aromatase inhibitors in these conditions, and review known and potential benefits, safety concerns, and shortcomings of the available information...

..A rise in bone turnover markers may be an early indicator of increase in BMD in recovering girls with AN...

..The effects of estrogen in weight recovered vs. non-weight recovered AN will also be studied. ..

..This research proposal will examine the impact of low fat mass and related hormones on absence of periods in these young women, and strategies to increase bone density at this critical time. ..