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1.
Nutrients ; 14(13)2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35807738

RESUMO

Background: While physiologic estrogen replacement results in increases in areal bone mineral density (aBMD) in hypoestrogenic adolescent girls and young adult women with AN, data are lacking regarding its impact on measures of volumetric BMD (vBMD), bone geometry, and structure. Methods: 23 young women with anorexia nervosa (AN) and 27 normal-weight healthy controls (HC) between 14−25 years old were followed for 12 months. AN participants received transdermal 17ß-estradiol (continuously) with 10 days of cyclic oral progesterone (100 mg daily) every month for the study duration (AN-E+). DXA was used to measure aBMD and body composition, high resolution peripheral quantitative CT (HRpQCT) to assess vBMD, bone geometry and structure at the distal radius and tibia, and microfinite element analysis to estimate strength. Results: Groups did not differ for age. Median baseline BMI z-scores were −1.13 (−1.58, −0.38) in AN-E+ vs. 0.08 (−0.40, 0.84) in HC (p < 0.0001). For most HRpQCT parameters and strength estimates, young women with AN receiving physiologic estrogen replacement demonstrated similar changes over 12 months as did normoestrogenic HC. Additionally, radial cortical tissue mineral density, cortical vBMD, and failure load increased (p = 0.01; p = 0.02; p = 0.004 respectively) over 12 months in AN-E+ compared to HC. Conclusions: With physiologic estrogen replacement, bone accrual improved in AN to approximate changes observed in normoestrogenic controls followed without any intervention, with additional benefits observed for cortical tissue mineral density, cortical vBMD, and failure load at the radius in AN vs. controls. Thus, this strategy for estrogen replacement effectively mimics the effects of endogenous estrogen on bone structure and estimated strength.


Assuntos
Anorexia Nervosa , Absorciometria de Fóton , Adolescente , Adulto , Anorexia Nervosa/tratamento farmacológico , Densidade Óssea/fisiologia , Osso e Ossos , Estradiol , Estrogênios , Feminino , Humanos , Tíbia , Adulto Jovem
2.
Front Oncol ; 12: 875122, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35646715

RESUMO

Epigenetic modification of chromatin is involved in non-malignant pituitary neoplasia by causing abnormal expression of tumor suppressors and oncogenes. These changes are potentially reversible, suggesting the possibility of targeting tumor cells by restoring the expression of epigenetically silenced tumor suppressors. The role of the histone deacetylase (HDAC) family in pituitary tumorigenesis is not known. We report that HDAC2 and 3, Class I HDAC members, are highly expressed in clinically non-functioning pituitary adenomas (NFPAs) compared to normal pituitary (NP) samples as determined by RT-PCR and immunohistochemical staining (IHC). Treatment of a human NFPA derived folliculostellate cell line, PDFS, with the HDAC3 inhibitor RGFP966 for 96 hours resulted in inhibition of cell proliferation by 70%. Furthermore, the combination of RGFP966 with a methyltransferase/DNMT inhibitor, 5'-aza-2'-deoxycytidine, led to the restoration of the expression of several tumor suppressor genes, including STAT1, P16, PTEN, and the large non-coding RNA tumor suppressor MEG3, in PDFS cells. Our data support the hypothesis that both histone modification and DNA methylation are involved in the pathogenesis of human NFPAs and suggest that targeting HDACs and DNA methylation can be incorporated into future therapies.

3.
Front Oncol ; 12: 875219, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35600354

RESUMO

Introduction: Angiogenesis in pituitary tumors is not fully understood, and a better understanding could help inform new pharmacologic therapies, particularly for aggressive pituitary tumors. Materials and Methods: 219 human pituitary tumors and 12 normal pituitary glands were studied. Angiogenic genes were quantified by an angiogenesis qPCR array and a TaqMan probe-based absolute qPCR. Angiogenesis inhibition in pituitary tumors was evaluated in vitro with the endothelial tube formation assay and in vivo in RbΔ19 mice. Results: 71 angiogenic genes, 40 of which are known to be involved in sprouting angiogenesis, were differentially expressed in pituitary tumors. Expression of endothelial markers CD31, CD34, and ENG was significantly higher in pituitary tumors, by 5.6, 22.3, and 8.2-fold, respectively, compared to in normal pituitary tissue. There was no significant difference in levels of the lymphatic endothelial marker LYVE1 in pituitary tumors compared with normal pituitary gland tissue. Pituitary tumors also expressed significantly higher levels of angiogenesis growth factors, including VEGFA (4.2-fold), VEGFB (2.2), VEGFC (19.3), PGF (13.4), ANGPT2 (9.2), PDGFA (2.7), PDGFB (10.5) and TGFB1 (3.8) compared to normal pituitary tissue. Expression of VEGFC and PGF was highly correlated with the expression of endothelial markers in tumor samples, including CD31, CD34, and ENG (endoglin, a co-receptor for TGFß). Furthermore, VEGFR inhibitors inhibited angiogenesis induced by human pituitary tumors and prolonged survival of RbΔ19 mice. Conclusion: Human pituitary tumors are characterized by more active angiogenesis than normal pituitary gland tissue in a manner consistent with sprouting angiogenesis. Angiogenesis in pituitary tumors is regulated mainly by PGF and VEGFC, not VEGFA and VEGFB. Angiogenesis inhibitors, such as the VEGFR2 inhibitor cabozantinib, may merit further investigation as therapies for aggressive human pituitary tumors.

4.
Front Endocrinol (Lausanne) ; 13: 1049541, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36798485

RESUMO

Objective: Anorexia nervosa (AN) is commonly associated with depression, anxiety, and deficits in socioemotional functioning. Basal levels of oxytocin, a neurohormone with antidepressant, anxiolytic, and prosocial properties, are low in women with AN. However, the relationship between oxytocin and psychopathology of AN/atypical AN has not been examined in individuals with primarily food restriction (AN/AtypAN-R) or those with restriction plus binge/purge behaviors (AN/AtypAN-BP) alone, which is important to further elucidate the neurobiology of different AN presentations. We investigated whether oxytocin levels are related to eating, affective, and socioemotional psychopathology in women with AN/AtypAN-R and separately AN/AtypAN-BP. Methods: In a cross-sectional study of 53 women with low-weight AN or atypical AN based on DSM-5 (AN/AtypAN-R: n=21, AN/AtypAN-BP: n=32), we obtained fasting serum oxytocin levels and self-report measures of psychopathology, including the Eating Disorder Examination-Questionnaire (EDE-Q), Beck Depression Inventory-IA (BDI), State-Trait Anxiety Inventory (STAI), and Toronto Alexithymia Scale (TAS-20). Results: In individuals with AN/AtypAN-R, oxytocin levels were negatively associated with eating psychopathology (EDE-Q Global Score: r=-0.49, p=0.024), depressive and anxiety symptoms (BDI Total Score: r=-0.55, p=0.009; STAI Trait Score: r=-0.63, p=0.002), and socioemotional symptoms (TAS-20 Difficulty Identifying Feelings Score: r=-0.49, p=0.023). In contrast, in those with AN/AtypAN-BP oxytocin levels were negatively associated with depressive symptoms only (BDI Total Score: r=-0.52, p=0.049). Conclusions: These findings support the notion that AN/AtypAN-R and AN/AtypAN-BP might have divergent underlying neurobiology. Understanding these differences is crucial to develop targeted treatments for a population with high levels of chronicity, for which no specific pharmacological treatments are currently available. Clinical trial registration: https://clinicaltrials.gov, identifier: NCT01121211.


Assuntos
Anorexia Nervosa , Humanos , Feminino , Anorexia Nervosa/complicações , Anorexia Nervosa/psicologia , Ocitocina , Estudos Transversais , Psicopatologia , Jejum
5.
Bone ; 154: 116214, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34571202

RESUMO

BACKGROUND: States of chronic overnutrition and undernutrition are both associated with impaired bone health and increased fracture risk but there are no data on bone microarchitecture following short-term controlled nutritional challenges. OBJECTIVE: The purpose of our study was to evaluate the impact of short-term high-caloric feeding and fasting on bone microarchitecture. We hypothesized that both high-caloric feeding and fasting would have negative effects on microarchitecture. MATERIALS AND METHODS: We recruited 23 adult healthy subjects (13 males, 10 females, mean age 33.2 ± 1.4 years, mean BMI 26.0 ± 1.5 kg/m2). Subjects underwent an in-patient 10-day high-caloric visit (caloric intake with goal to achieve 7% weight gain), after which they went home to resume a normal diet for 13-18 days (stabilization period), and were then readmitted for a 10-day in-patient fasting stay (no caloric intake). All subjects underwent HRpQCT (XtremeCT, Scanco Medical AG, Brüttisellen, Switzerland) of the distal tibia and distal radius after each visit to assess volumetric bone mineral density (vBMD), trabecular and cortical microarchitecture, and strength estimates. The Wilcoxon signed rank test was used to perform within group comparisons. RESULTS: During the high-caloric period, there was a mean increase in weight by 6.3 + 1.7% (p < 0.0001). There were no significant changes in bone parameters in the distal tibia or distal radius (p > 0.05). During the stabilization period there was a significant reduction in weight by -2.7 + 1.9% (p < 0.0001) but no change in bone parameters (p > 0.05). During the fasting period there was a further reduction in weight by -8.8 + 1.2% (p < 0.0001). In the distal tibia, there was a significant increase in total and cortical vBMD, trabecular and cortical parameters as well as strength estimates (p < 0.05). In the distal radius there was an increase in total and trabecular vBMD (p < 0.05), while there were no changes in other microarchitecture parameters or strengths estimates. CONCLUSION: Short-term fasting after high-caloric feeding improves vBMD, bone microarchitecture and strength estimates of the distal tibia, while short-term high-caloric feeding does not change vBMD or microarchitecture. These results suggest that short-term fasting after high-caloric feeding in healthy individuals improves bone health and that these changes can be detected using HRpQCT in-vivo.


Assuntos
Jejum , Rádio (Anatomia) , Absorciometria de Fóton , Adulto , Densidade Óssea , Osso e Ossos , Feminino , Humanos , Masculino , Tíbia/diagnóstico por imagem
6.
J Bone Miner Res ; 36(11): 2116-2126, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34355814

RESUMO

Anorexia nervosa is complicated by low bone mineral density (BMD) and increased fracture risk associated with low bone formation and high bone resorption. The lumbar spine is most severely affected. Low bone formation is associated with relative insulin-like growth factor 1 (IGF-1) deficiency. Our objective was to determine whether bone anabolic therapy with recombinant human (rh) IGF-1 used off-label followed by antiresorptive therapy with risedronate would increase BMD more than risedronate or placebo in women with anorexia nervosa. We conducted a 12-month, randomized, placebo-controlled study of 90 ambulatory women with anorexia nervosa and low areal BMD (aBMD). Participants were randomized to three groups: 6 months of rhIGF-1 followed by 6 months of risedronate ("rhIGF-1/Risedronate") (n = 33), 12 months of risedronate ("Risedronate") (n = 33), or double placebo ("Placebo") (n = 16). Outcome measures were lumbar spine (1° endpoint: postero-anterior [PA] spine), hip, and radius aBMD by dual-energy X-ray absorptiometry (DXA), and vertebral, tibial, and radial volumetric BMD (vBMD) and estimated strength by high-resolution peripheral quantitative computed tomography (HR-pCT) (for extremity measurements) and multi-detector computed tomography (for vertebral measurements). At baseline, mean age, body mass index (BMI), aBMD, and vBMD were similar among groups. At 12 months, mean PA lumbar spine aBMD was higher in the rhIGF-1/Risedronate (p = 0.03) group and trended toward being higher in the Risedronate group than Placebo. Mean lateral lumbar spine aBMD was higher, in the rhIGF-1/Risedronate than the Risedronate or Placebo groups (p < 0.05). Vertebral vBMD was higher, and estimated strength trended toward being higher, in the rhIGF-1/Risedronate than Placebo group (p < 0.05). Neither hip or radial aBMD or vBMD, nor radial or tibial estimated strength, differed among groups. rhIGF-1 was well tolerated. Therefore, sequential therapy with rhIGF-1 followed by risedronate increased lateral lumbar spine aBMD more than risedronate or placebo. Strategies that are anabolic and antiresorptive to bone may be effective at increasing BMD in women with anorexia nervosa. © 2021 American Society for Bone and Mineral Research (ASBMR).


Assuntos
Anorexia Nervosa , Densidade Óssea , Fator de Crescimento Insulin-Like I , Ácido Risedrônico/uso terapêutico , Absorciometria de Fóton , Anorexia Nervosa/complicações , Anorexia Nervosa/tratamento farmacológico , Feminino , Humanos , Fator de Crescimento Insulin-Like I/uso terapêutico , Vértebras Lombares/diagnóstico por imagem , Proteínas Recombinantes/uso terapêutico
7.
Bone ; 152: 116093, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34186250

RESUMO

BACKGROUND: Bone marrow adipose tissue (BMAT) plays a role in systemic energy metabolism and responds to nutritional changes. Chronic starvation as well as visceral adiposity are associated with BMAT accumulation. Two types of BMAT have been described which differ in anatomic location (proximal-regulated-rBMAT vs distal-constitutive-cBMAT) and composition (higher unsaturated lipids of cBMAT compared to rBMAT). OBJECTIVE: To determine the response of BMAT composition to short-term high-caloric feeding and fasting. We hypothesized that high-feeding and caloric restriction would be associated with differences in BMAT composition according to the skeletal site. MATERIALS AND METHODS: We examined 23 healthy subjects (13 m, 10 f, mean age 33 ± 7 years, BMI 26 ± 1.5 kg/m2) who were admitted for a 10-day high-caloric stay (caloric intake with goal to achieve 7% weight gain) followed by discharge home for 13-18 days to resume normal diet (stabilization period), followed by a 10-day fasting stay (no caloric intake). Subjects underwent single voxel proton MR spectroscopy (1H-MRS) at 3T of the lumbar spine (L4) (rBMAT), the femoral diaphysis and distal tibial metaphysis (cBMAT) to determine BMAT composition (unsaturation index, UI and saturation index, SI). Within group comparisons were performed by the Wilcoxon signed rank test. RESULTS: After the high-calorie visit, SI of L4 increased compared to baseline (0.62 ± 0.27 to 0.70 ± 0.28, p = 0.02), and there was a trend of an increase in femoral SI and UI (p ≥ 0.07), while there was no significant change in tibial BMAT (p ≥ 0.13). During the stabilization period, SI of L4 decreased (0.70 ± 0.28 to 0.57 ± 0.21, p < 0.0001) and SI of the femoral diaphysis decreased (5.37 ± 2.27 to 5.09 ± 2.43, p = 0.03), while there was no significant change in UI or tibial BMAT (p ≥ 0.14). During the fasting period, SI of L4 increased (0.57 ± 0.21 to 0.63 ± 0.30, p = 0.03), while there was no change in UI (p = 0.7). SI and UI of femoral diaphysis decreased (5.09 ± 2.43 to 4.68 ± 2.15, p = 0.03, and 0.62 ± 0.42 to 0.47 ± 0.37, p = 0.02, respectively) and UI of the tibial metaphysis decreased (1.48 ± 0.49 to 1.24 ± 0.57, p = 0.04). CONCLUSION: 1H-MRS is able to quantify BMAT composition during short-term nutritional challenges, showing a significant increase in SI of rBMAT during high caloric feeding and a differential response to fasting with an increase in SI of rBMAT and a decrease in SI and UI of femoral cBMAT and decrease in UI of tibial cBMAT.


Assuntos
Medula Óssea , Jejum , Tecido Adiposo , Adulto , Humanos , Vértebras Lombares , Tíbia
8.
JCI Insight ; 6(12)2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-33974568

RESUMO

BACKGROUNDAdipocytes were long considered inert components of the bone marrow niche, but mouse and human models suggest bone marrow adipose tissue (BMAT) is dynamic and responsive to hormonal and nutrient cues.METHODSIn this study of healthy volunteers, we investigated how BMAT responds to acute nutrient changes, including analyses of endocrine determinants and paracrine factors from marrow aspirates. Study participants underwent a 10-day high-calorie protocol, followed by a 10-day fast.RESULTSWe demonstrate (a) vertebral BMAT increased significantly during high-calorie feeding and fasting, suggesting BMAT may have different functions in states of caloric excess compared with caloric deprivation; (b) ghrelin, which decreased in response to high-calorie feeding and fasting, was inversely associated with changes in BMAT; and (c) in response to high-calorie feeding, resistin levels in the marrow sera, but not the circulation, rose significantly. In addition, TNF-α expression in marrow adipocytes increased with high-calorie feeding and decreased upon fasting.CONCLUSIONHigh-calorie feeding, but not fasting, induces an immune response in bone marrow similar to what has been reported in peripheral adipose tissue. Understanding the immunomodulatory regulators in the marrow may provide further insight into the homeostatic function of this unique adipose tissue depot.FUNDINGNIH grant R24 DK084970, Harvard Catalyst/The Harvard Clinical and Translational Science Center (National Center for Advancing Translational Sciences, NIH, award UL 1TR002541), and NIH grants P30 DK040561 and U19 AG060917S1.


Assuntos
Tecido Adiposo , Medula Óssea , Jejum/fisiologia , Tecido Adiposo/metabolismo , Tecido Adiposo/fisiologia , Adulto , Medula Óssea/metabolismo , Medula Óssea/fisiologia , Feminino , Humanos , Masculino
9.
J Clin Endocrinol Metab ; 106(7): 2021-2035, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-33693703

RESUMO

CONTEXT: Anorexia nervosa (AN) is prevalent in adolescent girls and is associated with bone impairment driven by hormonal alterations in nutritional deficiency. OBJECTIVE: To assess the impact of estrogen replacement with and without recombinant human insulin-like growth factor-1 (rhIGF-1) administration on bone outcomes. DESIGN: Double-blind, randomized, placebo-controlled 12-month longitudinal study. PARTICIPANTS: Seventy-five adolescent and young adult women with AN age 14 to 22 years. Thirty-three participants completed the study. INTERVENTION: Transdermal 17-beta estradiol 0.1 mg/day with (i) 30 mcg/kg/dose of rhIGF-1 administered subcutaneously twice daily (AN-IGF-1+) or (ii) placebo (AN-IGF-1-). The dose of rhIGF-1 was adjusted to maintain levels in the upper half of the normal pubertal range. MAIN OUTCOME MEASURES: Bone turnover markers and bone density, geometry, microarchitecture, and strength estimates. RESULTS: Over 12 months, lumbar areal bone mineral density increased in AN-IGF-1- compared to AN-IGF-1+ (P = 0.004). AN-IGF-1+ demonstrated no improvement in areal BMD in the setting of variable compliance to estrogen treatment. Groups did not differ for 12-month changes in bone geometry, microarchitecture, volumetric bone mineral density (vBMD), or strength (and results did not change after controlling for weight changes over 12 months). Both groups had increases in radial cortical area and vBMD, and tibia cortical vBMD over 12 months. Levels of a bone resorption marker decreased in AN-IGF-1- (P = 0.042), while parathyroid hormone increased in AN-IGF-1+ (P = 0.019). AN-IGF-1- experienced irregular menses more frequently than did AN-IGF-1+, but incidence of all other adverse events did not differ between groups. CONCLUSIONS: We found no additive benefit of rhIGF-1 administration for 12 months over transdermal estrogen replacement alone in this cohort of young women with AN.


Assuntos
Anorexia Nervosa/tratamento farmacológico , Estradiol/administração & dosagem , Terapia de Reposição de Estrogênios/métodos , Estrogênios/administração & dosagem , Fator de Crescimento Insulin-Like I/administração & dosagem , Administração Cutânea , Adolescente , Anorexia Nervosa/sangue , Biomarcadores/sangue , Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Estudos Longitudinais , Resultado do Tratamento , Adulto Jovem
10.
J Biol Chem ; 296: 100540, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33722609

RESUMO

The functions of long noncoding (lnc)RNAs, such as MEG3, are defined by their interactions with other RNAs and proteins. These interactions, in turn, are shaped by their subcellular localization and temporal context. Therefore, it is important to be able to analyze the relationships of lncRNAs while preserving cellular architecture. The ability of MEG3 to suppress cell proliferation led to its recognition as a tumor suppressor. MEG3 has been proposed to activate p53 by disrupting the interaction of p53 with mouse double minute 2 homolog (Mdm2). To test this mechanism in the native cellular context, we employed two-color direct stochastic optical reconstruction microscopy, a single-molecule localization microscopy technique, to detect and quantify the localizations of p53, Mdm2, and MEG3 in U2OS cells. We developed a new cross-nearest neighbor/Monte Carlo algorithm to quantify the association of these molecules. Proof of concept for our method was obtained by examining the association between FKBP1A and mTOR, MEG3 and p53, and Mdm2 and p53. In contrast to previous models, our data support a model in which MEG3 modulates p53 independently of the interaction with Mdm2.


Assuntos
Algoritmos , Método de Monte Carlo , Domínios e Motivos de Interação entre Proteínas , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , RNA Longo não Codificante/metabolismo , Imagem Individual de Molécula/métodos , Proteína Supressora de Tumor p53/metabolismo , Humanos , Processamento de Imagem Assistida por Computador/métodos , Microscopia de Fluorescência/métodos , Proteínas Proto-Oncogênicas c-mdm2/genética , RNA Longo não Codificante/genética , Proteína Supressora de Tumor p53/genética
11.
Bone ; 145: 115841, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33418100

RESUMO

CONTEXT: Low energy availability causes disruption of hypothalamic gonadotropin-releasing hormone secretion leading to functional hypothalamic amenorrhea (FHA) and hypoestrogenism, which in turn contributes to decreased bone mineral density (BMD) and increased bone marrow adipose tissue (MAT). Transdermal estradiol administration in physiologic doses increases BMD in adolescents and adults with FHA. However, the impact of estrogen replacement on MAT in relation to changes in BMD has not been studied in adolescents and young adults. We hypothesized that physiologic estrogen replacement would lead to decreases in MAT, associated with increases in BMD. METHODS AND MATERIALS: We studied 15 adolescent and young adult females with FHA (14-25 years). All participants received a17ß- estradiol transdermal patch at a dose of 0.1 mg/day (applied twice weekly) for 12 months. Participants also received cyclic progestin for 10-12 days each month. We quantified MAT (lipid/water ratio) of the fourth lumbar (L4) vertebral body and femoral diaphysis by single proton (1H)-magnetic resonance spectroscopy, and compartmental volumetric BMD of the distal radius and tibia using high-resolution peripheral quantitative computed tomography. RESULTS: Transdermal estradiol therapy over 12 months resulted in a decrease in MAT at the lumbar (L4) vertebra from 0.92 ± 0.55 at baseline to 0.63 ± 0.29 at 12-months (p = 0.008), and an increase in radial and tibial cortical vBMD (p = 0.006, p = 0.0003). Changes in L4 MAT trended to be inversely associated with changes in radial cortical vBMD (rho = -0.47, p = 0.08). CONCLUSION: We show that in adolescent and young adult girls with FHA, MAT decreases following transdermal estrogen therapy and these changes are associated with increased cortical vBMD.


Assuntos
Amenorreia , Medula Óssea , Tecido Adiposo , Adolescente , Amenorreia/tratamento farmacológico , Densidade Óssea , Estradiol , Estrogênios , Feminino , Humanos , Adulto Jovem
12.
Physiol Rep ; 8(24): e14639, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33369272

RESUMO

Neural processing of visual food stimuli is perturbated at extremes of weight. Human fMRI studies investigating diet effects on neural processing of food cues could aid in understanding altered brain activation in conditions of under- and overnutrition. In this preliminary study, we examined brain activity changes in response to 10 days of high-calorie-diet (HCD), followed by 10 days of fasting, hypothesizing that HCD would decrease activation in homeostatic and reward regions, while fasting would increase activation in homeostatic/reward regions and decrease activation of self-control regions. Seven adults completed fMRI scanning during a food-cue paradigm (high- and low-calorie food images and nonfood objects), pre- and post-10-day HCD. Six adults completed fMRI scanning pre- and post-10-day fasting. BOLD response changes for contrasts of interest pre- versus post-intervention in regions of interest were examined (peak-level significance set at p(FWE)<0.05). BMI increased by 6.8% and decreased by 8.1% following HCD and fasting, respectively. Following HCD, BOLD response in the hypothalamus (homeostatic control), was attenuated at trend level in response to high- versus low-calorie foods. Following fasting, BOLD response to food versus objects in inhibitory-control areas (dorsolateral prefrontal cortex) was reduced, whereas the activation of homeostatic (hypothalamus), gustatory, and reward brain areas (anterior insula and orbitofrontal cortex) increased. Overfeeding and fasting for 10 days modulate brain activity in response to food stimuli, suggesting that in healthy adults, changes in energy balance affect saliency and reward value of food cues. Future studies are required to understand this interaction in states of unhealthy weight.


Assuntos
Apetite , Encéfalo/fisiologia , Jejum/fisiologia , Alimentos , Percepção Visual , Adulto , Encéfalo/diagnóstico por imagem , Sinais (Psicologia) , Jejum/psicologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
13.
J Clin Endocrinol Metab ; 105(6)2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32133504

RESUMO

CONTEXT: The diagnosis of Cushing syndrome (CS) can be challenging. It remains to be determined which diagnostic tests are the most accurate. OBJECTIVE: To summarize the accuracy of diagnostic tests for CS using contemporary meta-analytic techniques (hierarchical models). DATA SOURCES: PubMed, Embase, Scopus, Web of Science, and the Cochrane Database of Systemic Reviews (inception until August 3, 2018). STUDY SELECTION: Studies performed in adults that determined the accuracy of one or more diagnostic tests: overnight 1-mg dexamethasone suppression test (DST), 2-day low-dose DST (2d DST), 24-hour urinary free cortisol (UFC), late-night salivary cortisol (LNSC), midnight serum cortisol (MSC), and the dexamethasone-suppressed CRH (dex-CRH) and desmopressin (dex-DDAVP) tests. DATA EXTRACTION: Two authors independently extracted data and performed methodological assessments. DATA SYNTHESIS: One hundred thirty-nine studies (14 140 participants) were included in the analysis. The respective sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio (95% confidence interval [CI]) estimates include the following: DST 98.6% (96.9%-99.4%), 90.6% (86.4%-93.6%), 10.5 (7.2-15.3), and 0.016 (0.007-0.035); 2d DST 95.3% (91.3%-97.5%), 92.8% (85.7%-96.5%), 13.2 (6.47-27.1), and 0.051 (0.027-0.095); UFC 94.0% (91.6%-95.7%), 93.0% (89.0%-95.5%), 13.3 (8.47-21.0), and 0.065 (0.046-0.092); LNSC 95.8% (93.%-97.2%), 93.4% (90.7%-95.4%), 14.6 (10.3-20.7), and 0.045 (0.030-0.066); MSC 96.1% (93.5%-97.6%), 93.2% (88.1%-96.3%), 14.2 (7.96-25.2), and 0.042 (0.026-0.069); and dex-CRH 98.6% (90.4%-99.8%), 85.9% (67.6%-94.7%), 7.0 (2.80-17.6), and 0.016 (0.002-0.118). A single study evaluated dex-DDAVP. Meta-regression and a novel network meta-analytic approach suggest that DST is the most sensitive while UFC is the least sensitive. CONCLUSIONS: All of the included diagnostic tests for CS are highly sensitive and specific. It appears that the DST is the most sensitive while the UFC is less sensitive. The specificity of all first-line tests appears comparable.


Assuntos
Biomarcadores/metabolismo , Técnicas de Laboratório Clínico/normas , Síndrome de Cushing/diagnóstico , Hidrocortisona/metabolismo , Síndrome de Cushing/metabolismo , Humanos , Metanálise como Assunto , Prognóstico , Curva ROC
14.
J Bone Miner Res ; 35(6): 1031-1039, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32078187

RESUMO

Bone marrow adipose tissue (BMAT) resides within the bone marrow microenvironment where its function remains poorly understood. BMAT is elevated in anorexia nervosa, a disease model of chronic starvation, despite depletion of other fat depots. In addition to BMAT, the marrow microenvironment also consists of osteoblast and hematopoietic progenitors. BMAT is inversely associated with bone mineral density (BMD) in multiple populations including women with anorexia nervosa, and regulates hematopoiesis in animal models. We hypothesized that BMAT would be associated with circulating populations of hematopoietic cells (red and white blood cells) in humans and performed a post hoc analysis of two studies-a cross-sectional study and a longitudinal study-to investigate this hypothesis. We studied 89 premenopausal women cross-sectionally (median age [interquartile range], 27 [24.5, 31.7] years), including 35 with anorexia nervosa. We investigated associations between red blood cell (RBC) and white blood cell (WBC) counts and BMAT assessed by 1 H-magnetic resonance spectroscopy, BMD assessed by DXA, and bone microarchitecture assessed by HR-pQCT. In addition, we analyzed longitudinal data in six premenopausal women with anorexia nervosa treated with transdermal estrogen for 6 months and measured changes in BMAT and blood cell counts during treatment. Cross-sectionally, BMAT was inversely associated with WBC and RBC counts. In contrast, BMD and parameters of bone microarchitecture were positively associated with WBC and RBC. In women with anorexia nervosa treated with transdermal estrogen for 6 months, decreases in BMAT were significantly associated with increases in both RBC and hematocrit (rho = -0.83, p = 0.04 for both). In conclusion, we show that BMAT is inversely associated with WBC and RBC in premenopausal women, and there is a potential association between longitudinal changes in BMAT and changes in RBC. These associations warrant further study and may provide further insight into the role and function of this understudied adipose depot. © 2020 American Society for Bone and Mineral Research.


Assuntos
Densidade Óssea , Medula Óssea , Tecido Adiposo/diagnóstico por imagem , Adulto , Medula Óssea/diagnóstico por imagem , Estudos Transversais , Feminino , Humanos , Contagem de Leucócitos , Estudos Longitudinais
15.
Eur J Endocrinol ; 182(3): 285-292, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31917681

RESUMO

OBJECTIVE: To examine all-cause mortality rates in patients with acromegaly on pegvisomant and identify pertinent risk factors, including insulin-like growth factor I (IGF-I). DESIGN: Retrospective cohort analysis of data from ACROSTUDY (global surveillance study of patients with acromegaly treated with pegvisomant). METHODS: Kaplan-Meier analyses and Cox regression techniques were used to examine survival rates. Standardized mortality ratios (SMR) with reference to general population (WHO GBD 2016) were estimated. Multiplicative multiple Poisson regression models were used to characterize the association between SMR, IGF-I, and other risk factors associated with mortality risk. RESULTS: The study consisted of 2077 subjects who were followed for a median interval of 4.1 years, contributing to 8957 patient-years. Higher on-treatment IGF-I (P = 0.0035), older attained age (P < 0.0001), and longer duration of acromegaly (>10 years) before starting pegvisomant (P = 0.05) were associated with higher mortality rates. In reference to general population rates, higher SMR (1.10, 1.42, and 2.62, at attained age 55 years) were observed with higher serum IGF-I category (SMR trend: 1.44 (44%)/per fold level of IGF-I/ULN (95% CI: 1.10, 1.87), P = 0.0075). SMR increased per year of younger attained age (1.04 (1.02-1.04), P < 0.0001) and were higher for longer disease duration (>10 years) before starting pegvisomant (1.57 (1.02, 2.43), P = 0.042). Serum IGF-I levels within the normal range during pegvisomant therapy were associated with all-cause mortality rates that were indistinguishable from the general population. CONCLUSIONS: Higher on-treatment IGF-I, older attained age, and longer duration of acromegaly before starting pegvisomant are associated with higher all-cause mortality rates. Younger patients with uncontrolled acromegaly have higher excess all-cause mortality rates in comparison with older patients.


Assuntos
Acromegalia/tratamento farmacológico , Hormônio do Crescimento Humano/análogos & derivados , Mortalidade , Receptores da Somatotropina/antagonistas & inibidores , Acromegalia/metabolismo , Adulto , Fatores Etários , Idoso , Causas de Morte , Estudos de Coortes , Feminino , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Tempo para o Tratamento
16.
Pituitary ; 23(3): 212-222, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31897778

RESUMO

PURPOSE: Given the paucity of reliable predictors of tumor recurrence, progression, or response to somatostatin receptor ligand (SRL) therapy in acromegaly, we attempted to determine whether preoperative MR image texture was predictive of these clinical outcomes. We also determined whether image texture could differentiate somatotroph adenomas from non-functioning pituitary adenomas (NFPAs). METHODS: We performed a retrospective study of patients with acromegaly due to a macroadenoma who underwent transsphenoidal surgery at our institution between 2007 and 2015. Clinical data were extracted from electronic medical records. MRI texture analysis was performed on preoperative non-enhanced T1-weighted images using ImageJ (NIH). Logistic and Cox models were used to determine if image texture parameters predicted outcomes. RESULTS: Eighty-nine patients had texture parameters measured, which were compared to that of NFPAs, while 64 of these patients had follow-up and were included in the remainder of analyses. Minimum pixel intensity, skewness, and kurtosis were significantly different in somatotroph adenomas versus NFPAs (area under the receiver operating characteristic curve, 0.7771, for kurtosis). Furthermore, those with a maximum pixel intensity above the median had an increased odds of IGF-I normalization on SRL therapy (OR 5.96, 95% CI 1.33-26.66), which persisted after adjusting for several potential predictors of response. Image texture did not predict tumor recurrence or progression. CONCLUSION: Our data suggest that MRI texture analysis can distinguish NFPAs from somatotroph macroadenomas with good diagnostic accuracy and can predict normalization of IGF-I with SRL therapy.


Assuntos
Acromegalia/diagnóstico por imagem , Acromegalia/metabolismo , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/metabolismo , Receptores de Somatostatina/metabolismo , Adulto , Feminino , Adenoma Hipofisário Secretor de Hormônio do Crescimento/diagnóstico por imagem , Adenoma Hipofisário Secretor de Hormônio do Crescimento/metabolismo , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Modelos Logísticos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Curva ROC , Estudos Retrospectivos
17.
Neurobiol Aging ; 88: 137-149, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31948671

RESUMO

Sex steroid hormones and neurotrophic factors, such as brain-derived neurotrophic factor (BDNF), play a significant neuroprotective role in memory circuitry aging. Here, we present findings characterizing the neuroprotective effects of BDNF on memory performance, as a function of sex and reproductive status in women. Participants (N = 191; mean age = 50.03 ± 2.10) underwent clinical and cognitive testing, fMRI scanning, and hormonal assessments of menopausal staging. Memory performance was assessed with the 6-Trial Selective Reminding Test and the Face-Name Associative Memory Exam. Participants also performed a working memory (WM) N-back task during fMRI scanning. Results revealed significant interactions between menopausal status and BDNF levels. Only in postmenopausal women, lower plasma BDNF levels were associated with significantly worse memory performance and altered function in the WM circuitry. BDNF had no significant impact on memory performance or WM function in pre/perimenopausal women or men. These results suggest that in postmenopausal women, BDNF is associated with memory performance and memory circuitry function, thus providing evidence of potential sex-dependent factors of risk and resilience for early intervention.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/fisiologia , Encéfalo/fisiologia , Memória/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Cognição , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Memória de Curto Prazo/fisiologia , Menopausa , Pessoa de Meia-Idade , Fármacos Neuroprotetores , Testes Neuropsicológicos , Reprodução , Caracteres Sexuais
18.
J Bone Miner Res ; 35(2): 248-260, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31603998

RESUMO

Oligoamenorrheic athletes (OAs) have lower bone mineral density (BMD) and greater impairment of bone microarchitecture, and therefore higher fracture rates compared to eumenorrheic athletes. Although improvements in areal BMD (aBMD; measured by dual-energy X-ray absorptiometry) in OAs have been demonstrated with transdermal estrogen treatment, effects of such treatment on bone microarchitecture are unknown. Here we explore effects of transdermal versus oral estrogen versus no estrogen on bone microarchitecture in OA. Seventy-five OAs (ages 14 to 25 years) were randomized to (i) a 100-µg 17ß-estradiol transdermal patch (PATCH) administered continuously with 200 mg cyclic oral micronized progesterone; (ii) a combined 30 µg ethinyl estradiol and 0.15 mg desogestrel pill (PILL); or (iii) no estrogen/progesterone (NONE) and were followed for 12 months. Calcium (≥1200 mg) and vitamin D (800 IU) supplements were provided to all. Bone microarchitecture was assessed using high-resolution peripheral quantitative CT at the distal tibia and radius at baseline and 1 year. At baseline, randomization groups did not differ by age, body mass index, percent body fat, duration of amenorrhea, vitamin D levels, BMD, or bone microarchitecture measurements. After 1 year of treatment, at the distal tibia there were significantly greater increases in total and trabecular volumetric BMD (vBMD), cortical area and thickness, and trabecular number in the PATCH versus PILL groups. Trabecular area decreased significantly in the PATCH group versus the PILL and NONE groups. Less robust differences between groups were seen at the distal radius, where percent change in cortical area and thickness was significantly greater in the PATCH versus PILL and NONE groups, and changes in cortical vBMD were significantly greater in the PATCH versus PILL groups. In conclusion, in young OAs, bone structural parameters show greater improvement after 1 year of treatment with transdermal 17ß-estradiol versus ethinyl estradiol-containing pills, particularly at the tibia. © 2019 American Society for Bone and Mineral Research.


Assuntos
Terapia de Reposição de Estrogênios , Absorciometria de Fóton , Adolescente , Adulto , Atletas , Densidade Óssea , Feminino , Humanos , Rádio (Anatomia) , Tíbia , Adulto Jovem
19.
Psychoneuroendocrinology ; 112: 104512, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31780185

RESUMO

The neuroactive steroid 3α-5α-tetrahydroprogesterone (allopregnanolone), a metabolite of progesterone, is a positive allosteric modulator of GABAA receptors, and low levels have been implicated in the etiology of mood disorders. However, it is not known whether metabolism of progesterone to allopregnanolone varies across the menstrual cycle or is low after menopause. We hypothesized that the allopregnanolone/progesterone ratio would decrease from the follicular to luteal phase. We also hypothesized that postmenopausal women would have lower levels of progesterone and allopregnanolone but similar allopregnanolone/progesterone ratios as premenopausal women in the follicular phase. Serum fasting allopregnanolone and progesterone levels were measured by gas chromatography-mass spectrometry in ten premenopausal women at the follicular, mid-cycle, and luteal phases of the menstrual cycle and in twenty-four postmenopausal women. Although allopregnanolone and progesterone levels increased from the follicular to luteal phase, the allopregnanolone/progesterone ratio decreased 8-fold [0.33 ± 0.08 (follicular) vs 0.16 ± 0.09 (mid-cycle) vs 0.04 ± 0.007 (luteal), p = 0.0003]. Mean allopregnanolone and progesterone levels were lower in postmenopausal than premenopausal women at all menstrual cycle phases (p < 0.01). The mean allopregnanolone/progesterone ratio was similar in postmenopausal and premenopausal women in the follicular phase (0.39 ± 0.08 vs 0.33 ± 0.08, p = 0.94) but was significantly lower at mid-cycle and in the luteal phase than in postmenopausal women (p < 0.01). In conclusion, the serum allopregnanolone/progesterone ratio decreases 8-fold from the follicular to luteal phase and is lower at mid-cycle and the luteal phase than in postmenopausal women. Whether these data have implications for luteal phase and other mood disorders merits further study.


Assuntos
Fase Folicular/sangue , Fase Luteal/sangue , Menopausa/sangue , Pregnanolona/sangue , Progesterona/sangue , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem
20.
PLoS One ; 14(10): e0224103, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31648221

RESUMO

BACKGROUND: Midkine (MDK), one of the heparin-binding growth factors, is highly expressed in multiple organs during embryogenesis. Plasma concentrations have been reported to be elevated in patients with a variety of malignancies, in adults with obesity, and in children with short stature, diabetes, and obesity. However, the concentrations in healthy children and their relationships to age, nutrition, and linear growth have not been well studied. SUBJECTS AND METHODS: Plasma MDK was measured by immunoassay in 222 healthy, normal-weight children (age 0-18 yrs, 101 boys), 206 healthy adults (age 18-91 yrs, 60 males), 61 children with BMI ≥ 95th percentile (age 4-18 yrs, 20 boys), 20 girls and young women with anorexia nervosa (age 14-23 yrs), and 75 children with idiopathic short stature (age 3-18 yrs, 42 boys). Body fat was evaluated by dual-energy X-ray absorptiometry (DXA) in a subset of subjects. The associations of MDK with age, sex, adiposity, race/ethnicity and stature were evaluated. RESULTS: In healthy children, plasma MDK concentrations declined with age (r = -0.54, P < 0.001) with values highest in infants. The decline occurred primarily during the first year of life. Plasma MDK did not significantly differ between males and females or between race/ethnic groups. MDK concentrations were not correlated with BMI SDS, fat mass (kg) or percent total body fat, and no difference in MDK was found between children with anorexia nervosa, healthy weight and obesity. For children with idiopathic short stature, MDK concentrations did not differ significantly from normal height subjects, or according to height SDS or IGF-1 SDS. CONCLUSIONS: In healthy children, plasma MDK concentrations declined with age and were not significantly associated with sex, adiposity, or stature-for-age. These findings provide useful reference data for studies of plasma MDK in children with malignancies and other pathological conditions.


Assuntos
Adiposidade , Biomarcadores/sangue , Nanismo/diagnóstico , Transtornos do Crescimento/diagnóstico , Midkina/sangue , Obesidade/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Criança , Pré-Escolar , Nanismo/sangue , Feminino , Transtornos do Crescimento/sangue , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Adulto Jovem
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