169 research outputs found

    The effects of anorexia nervosa on bone metabolism in female adolescents

    Get PDF
    Osteopenia is a frequent, often persistent, complication of anorexia nervosa (AN) in adolescent girls and occurs during a critical time in bone development. Little is known about bone metabolism in this patient population. Therefore, we measured bone density (BMD) and body composition by dual energy x-ray absorptiometry, nutritional status, bone turnover, calcium, and hormonal status in 19 adolescent girls with AN (mean +/- SEM, 16.0+/-0.4 yr) and 19 bone age-matched controls. The mean duration of AN was 19+/-5 months. Spinal (L1-L4) osteopenia was common in AN. Lumbar anterioposterior BMD was more than 1 SD below the mean in 42% of patients, and lateral spine BMD was more than 1 SD below in 63% of patients compared with controls. Lean body mass significantly predicted lumbar bone mineral content (r = 0.75; P \u3c 0.0001) in controls only. In AN, duration of illness was the most significant predictor of spinal BMD (lumbar: r = -0.44; P = 0.06; lateral: r = -0.59; P = 0.008). AN adolescents with mature BA (15 yr and greater) were hypogonadal [estradiol, 16.2+/-1.9 vs. 23.3+/-1.6 pg/mL (P = 0.01); free testosterone, 0.70+/-0.17 vs. 1.36+/-0.14 pg/mL (P = 0.01)] although dehydroepiandrosterone sulfate and urinary free cortisol levels did not differ. Leptin levels were reduced in AN (2.9+/-2.1 vs. 16.5+/-1.8 ng/mL; P \u3c 0.0001). Insulin-like growth factor I (IGF-I) was reduced in AN to 50% of control levels (219+/-41 vs. 511+/-35 ng/mL; P \u3c 0.0001) and correlated with all measures of nutritional status, particularly leptin (r = 0.80; P \u3c 0.0001). Surrogate markers of bone formation, serum osteocalcin (OC) and bone-specific alkaline phosphatase (BSAP), were significantly (P = 0.02) reduced in AN vs. controls (OC, 39.1+/-6.4 vs. 59.2+/-5.2 ng/mL; BSAP, 27.9+/-4.0 vs. 40.6+/-3.4 U/L). The majority of the variation in bone formation in AN was due to IGF-I levels (OC: r2 = 0.72; P = 0.002; BSAP: r2 = 0.53; P = 0.01) in stepwise regression analyses. Bone resorption was comparable in patients and controls. These data demonstrate that bone formation is reduced and uncoupled to bone resorption in mature adolescents with AN in association with low bone density. Lean body mass was a significant predictor of BMD in controls, but not AN patients. The major correlate of bone formation in AN was the nutritionally dependent bone trophic factor, IGF-I. Reduced IGF-I during the critical period of bone mineral accumulation may be an important factor in the development of osteopenia in adolescents with AN

    Relationship Between Neck Circumference and Cardiometabolic Parameters in HIV-Infected and non–HIV-Infected Adults

    Get PDF
    OBJECTIVE: Upper body fat is associated with increased cardiometabolic risk. More recently, neck circumference (NC) and/or neck fat have been associated with hyperlipidemia, impaired glucose homeostasis, and hypertension. The objective of this study was to determine whether this relationship is evident in HIV-infected individuals, who often exhibit changes in relative fat distribution, and to determine whether NC is independently associated with carotid intima-media thickness (cIMT) in HIV and non–HIV-infected patients. RESEARCH DESIGN AND METHODS: Body composition, including anthropometrics, visceral adipose tissue assessment by CT, and metabolic parameters, including lipids, cIMT, and oral glucose tolerance test, were measured in 174 men and women with HIV infection and 154 non–HIV-infected subjects. NC was measured in triplicate inferior to the laryngeal prominence. RESULTS: In univariate analysis, NC was significantly and positively related to blood pressure, hemoglobin A1c, glucose, and insulin and significantly and negatively related to HDL cholesterol in HIV-infected individuals and HIV-negative control subjects. NC was significantly associated with cIMT in univariate regression analysis among HIV-infected (r = 0.21, P = 0.006) and non–HIV-infected (r = 0.31, P = 0.0001) patients. This relationship remained significant among non–HIV-infected patients (R2 = 0.45, P < 0.001) but not HIV-infected patients in multivariate modeling controlling for age, sex, race, smoking hypertension, glucose, and lipids. CONCLUSIONS: Among both HIV and non–HIV-infected patients, increased NC is strongly associated with decreased HDL and impaired glucose homeostasis. Among non–HIV-infected subjects, NC also predicts increased cIMT when controlling for traditional risk factors

    Abnormal bone mineral accrual in adolescent girls with anorexia nervosa

    Get PDF
    Anorexia nervosa (AN) is increasingly common in adolescent girls and occurs at a time of peak bone mass formation. Osteopenia is common in adolescent girls with AN, and in a cross-sectional study, we have reported low bone formation markers in such girls. To determine the impact of chronic undernutrition on bone mineral accrual in contrast to healthy controls, we prospectively measured bone mineral density (BMD) and body composition by dual energy x-ray absorptiometry, bone metabolism markers, and nutritional and hormonal status at baseline, 6 months, and 12 months in 19 adolescent girls with AN (mean +/- SEM, 15.4 +/- 0.4 yr) and 19 controls of comparable chronological and skeletal age. Overall, nutritional status in subjects with AN improved (mean percentage increase in body mass index from baseline, 9.2 +/- 1.9% and 15.2 +/- 2.6% at 6 and 12 months, respectively), with 11 subjects having recovered weight at 12 months. However, lumbar BMD at 12 months (AN, 0.88 +/- 0.02 g/cm(2), vs. control, 0.98 +/- 0.03 g/cm(2); P = 0.008) remained significantly reduced in AN compared with controls, even in recovered subjects. This was due to significant increases in lumbar BMD in controls vs. no change in AN subjects over the year (0.003 +/- 0.001 g/cm(2).month vs. 0.000 +/- 0.001 g/cm(2).month, respectively; P = 0.04). The most significant determinant of change in lumbar BMD at 12 months was change in lean body mass in both AN (r = 0.62; P = 0.008) and control (r = 0.80; P = 0.0006) groups. There were significant increases in surrogate markers of bone turnover in subjects with AN compared with controls as assessed by osteocalcin (AN, 0.9 +/- 0.4 micro g/liter.month, vs. control, -1.1 +/- 0.4 micro g/liter.month; P = 0.0007), bone-specific alkaline phosphatase (AN, 0.6 +/- 0.5 U/liter.month, vs. control, -1.5 +/- 0.4 U/liter.month; P = 0.002), deoxypyridinoline [AN, 0.1 +/- 0.1 nmol/mmol creatinine (cr).month, vs. control, -0.4 +/- 0.1 nmol/mmol cr.month; P = 0.005], and N-telopeptide (AN, 4 +/- 4 nmol BCE/mmol cr/month, vs. control, -9 +/- 4 nmol BCE/mmol cr/month; P = 0.01). Changes in IGF-I levels over the year were highly correlated with changes in bone turnover over the same period in AN (osteocalcin, r = 0.77; P = 0.001; deoxypyridinoline, r = 0.66; P = 0.01). A rise in N-telopeptide over the year was correlated with an increase in all bone mineral measures, including lumbar bone mineral content (r = 0.58; P = 0.03) and BMD (r = 0.53; P = 0.05) and total bone mineral content (r = 0.69; P = 0.006) and BMD (r = 0.69; P = 0.006) in the AN group. Therefore, despite recovery over 1 yr, poor bone mineral accrual persists in adolescent girls with AN in contrast to rapid bone accrual in healthy girls. Normalization of bone turnover markers occurs in association with nutritional recovery and an increase in the nutritionally dependent bone trophic factor IGF-I. A rise in bone turnover markers may be an early indicator of increase in BMD in recovering girls with AN

    Serum osteoprotegerin in adolescent girls with anorexia nervosa

    Get PDF
    Low bone mineral density (BMD) in adolescents with anorexia nervosa (AN) is associated with a low bone turnover state. Osteoprotegerin (OPG), a cytokine that acts as a decoy receptor for receptor activator of nuclear factor-kappaB ligand, decreases bone resorption by inhibiting differentiation of osteoclast precursors and activation of mature osteoclasts, and by stimulating osteoclast apoptosis. We compared OPG levels in 43 adolescent girls with AN with 38 controls and examined bone density, bone turnover, and hormonal parameters. Girls with AN had lower fat mass, lean body mass, lumbar BMD z-scores, and lumbar bone mineral apparent density than controls. OPG levels were higher in girls with AN than in controls (44.5 +/- 22.5 pg/ml vs. 34.5 +/- 12.7 pg/ml, P = 0.02). Osteocalcin, deoxypyridinoline, estradiol, free testosterone, IGF-I, and leptin were lower in AN than in healthy adolescents. OPG values correlated negatively with body mass index (r = -0.27, P = 0.02), percent fat mass (r = -0.35, P = 0.0002), leptin (r = -0.28, P = 0.02), lumbar BMD z-scores (r = -0.25, P = 0.03), and lumbar bone mineral apparent density (r = -0.26, P = 0.03). In conclusion, adolescent girls with AN have higher serum OPG values than controls. 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

    Increased Coronary Atherosclerotic Plaque Vulnerability by Coronary Computed Tomography Angiography in HIV-Infected Men

    Get PDF
    a Objective: Among HIV-infected patients, high rates of MI and sudden cardiac death have been observed. Exploring potential underlying mechanisms, we used multidetector spiral coronary computed tomography angiography (coronary CTA) to compare atherosclerotic plaque morphology in HIV-infected subjects and non-HIVinfected controls. Methods: Coronary atherosclerotic plaques visualized by CTA in HIV-infected (101) and non-HIV-infected (41) men without clinically apparent heart disease matched on cardiovascular risk factors were analyzed for 3 vulnerability features: low attenuation, positive remodeling, and spotty calcification. Results: 95% of HIV-infected subjects were receiving ART (median duration 7.9 years) and had well-controlled disease (median CD4 473 cells/mm3, median HIV RNA &lt;50 copies/ml). Age and traditional cardiovascular risk factors were similar in HIV-infected subjects and controls. Among the HIV-infected (versus control) group, there was a higher prevalence of subjects with at least one: 1) low attenuation plaque (22.8% versus 7.3%, p ¼ 0.02), 2) positively remodeled plaque (49.5% versus 31.7%, p ¼ 0.05) and 3) high-risk 3-feature plaque (7.9% versus 0%, p ¼ 0.02). Moreover, subjects in the HIVinfected (versus control) group demonstrated a higher number of low attenuation plaques (p ¼ 0.01) and positively remodeled plaques (p ¼ 0.03) per subject. Conclusions: Our data demonstrate an increased prevalence of vulnerable plaque features among relatively young HIV-infected patients. Differences in coronary atherosclerotic plaque morphology -namely, increased vulnerable plaque among HIVinfected subjects -are here for the first time reported and may contribute to increased rates of MI and sudden cardiac death in this population

    Altered miRNA processing disrupts brown/white adipocyte determination and associates with lipodystrophy

    Get PDF
    miRNAs are important regulators of biological processes in many tissues, including the differentiation and function of brown and white adipocytes. the endoribonuclease dicer is a major component of the miRNA-processing pathway, and in adipose tissue, levels of dicer have been shown to decrease with age, increase with caloric restriction, and influence stress resistance. Here, we demonstrated that mice with a fat-specific KO of dicer develop a form of lipodystrophy that is characterized by loss of intra-abdominal and subcutaneous white fat, severe insulin resistance, and enlargement and whitening of interscapular brown fat. Additionally, KO of dicer in cultured brown preadipocytes promoted a white adipocyte-like phenotype and reduced expression of several miRNAs. Brown preadipocyte whitening was partially reversed by expression of miR-365, a miRNA known to promote brown fat differentiation; however, introduction of other miRNAs, including miR-346 and miR-362, also contributed to reversal of the loss of the dicer phenotype. Interestingly, fat samples from patients with HIV-related lipodystrophy exhibited a substantial downregulation of dicer mRNA expression. Together, these findings indicate the importance of miRNA processing in white and brown adipose tissue determination and provide a potential link between this process and HIV-related lipodystrophy.NIHEllison FoundationJoslin Diabetes and Endocrinology Research Center coresMary K. Iacocca ProfessorshipAcademy of FinlandSigrid Juselius FoundationFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Harvard Univ, Sch Med, Joslin Diabet Ctr, Sect Integrat Physiol & Metab, Boston, MA 02115 USAUniversidade Federal de São Paulo, Dept Biophys, São Paulo, BrazilUniversidade Federal de São Paulo, Program Mol Biol, São Paulo, BrazilAstraZeneca R&D, Cardiovasc & Metab Dis iMed, Molndal, SwedenUniv Helsinki, Dept Med, Helsinki, FinlandMinerva Fdn, Inst Med Res, Helsinki, FinlandUniv Massachusetts, Sch Med, Program Mol Med, Worcester, MA USAMassachusetts Gen Hosp, Program Nutr Metab, Boston, MA 02114 USAHarvard Univ, Sch Med, Boston, MA USAUniversidade Federal de São Paulo, Dept Biophys, São Paulo, BrazilUniversidade Federal de São Paulo, Program Mol Biol, São Paulo, BrazilNIH: DK082659NIH: DK033201NIH: AI060354NIH: DK040561NIH: U24-DK093000Joslin Diabetes and Endocrinology Research Center cores: DK036836FAPESP: 2010/52557-0Web of Scienc

    Reduced ovarian reserve relates to monocyte activation and subclinical coronary atherosclerotic plaque in women with HIV

    Get PDF
    Objective: To investigate differences in subclinical coronary atherosclerotic plaque and markers of immune activation among HIV-infected and non-HIV-infected women categorized by degree of ovarian reserve and menopause status. Design: Cross-sectional evaluation. Methods: Seventy-four women (49 HIV-infected, 25 non-HIV-infected) without known cardiovascular disease (CVD) were classified as premenopausal, premenopausal with reduced ovarian reserve, or postmenopausal based on menstrual history and anti-Mü llerian hormone (AMH) levels. Participants underwent contrast-enhanced coronary computed tomography angiography and immune phenotyping. Comparisons in coronary atherosclerotic plaque burden and immune markers were made between the HIV-infected and non-HIV-infected women overall and within the HIV-infected and non-HIV-infected women by reproductive classification group. Results: Among the overall group of HIV-infected women, the women with reduced ovarian reserve (undetectable AMH) had a higher prevalence of coronary atherosclerotic plaque (52 versus 6%, P ¼ 0.0007) and noncalcified plaque (48 versus 6%, P ¼ 0.002), as well as higher levels of log sCD163 (P ¼ 0.0004) and log MCP-1 (P ¼ 0.006), compared with the premenopausal women with measurable AMH. Furthermore, reduced ovarian reserve in the HIV-infected group related to noncalcified plaque, controlling for traditional CVD risk factors (P ¼ 0.04) and sCD163 (P ¼ 0.03). Conclusion: HIV-infected women with reduced ovarian reserve have increased subclinical coronary atherosclerotic plaque compared with premenopausal women in whom AMH is measurable. This relationship holds when controlling for CVD risk factors (including age) and immune activation. Our findings demonstrate that reduced ovarian reserve may contribute to CVD burden in HIV-infected women and support a comprehensive assessment of CVD risk prior to completion of menopause in this population

    Ideal cardiovascular health, biomarkers, and coronary artery disease in persons with HIV

    Get PDF
    OBJECTIVE: To investigate relationships between Life\u27s Simple 7 (LS7), an assessment of cardiovascular health (CVH), and coronary plaque among people with HIV (PWH). DESIGN: Cross-sectional. METHODS: Coronary computed tomography angiography, immune/inflammatory biomarkers, and characterization of LS7 were collected among a subset of ART-treated PWH enrolled in REPRIEVE, a primary prevention trial. Analyses adjusted for cardiovascular disease risk (ASCVD score). RESULTS: Median age of the 735 participants was 51(±6) years, 16% female, and median (Q1-Q3) CVD risk was 4.5% (2.6-6.9). Forty percent had poor (≤2 ideal components), 51% had intermediate (three or four ideal components), and only 9% had ideal CVH (≥5). Coronary plaque was present in 357 (49%); 167 (23%) had one or more vulnerable plaque features, 293 (40%) had noncalcified plaque, and 242 (35%) had a coronary artery calcium score \u3e0. All three phenotypes were increasingly more prevalent with poorer CVH and these relationships remained after adjusting for ASCVD risk. Poor CVH was associated with higher high-sensitivity C-reactive protein, oxidized low-density cholesterol, and interleukin-6. The relationship of LS7 to plaque remained after adjusting for these biomarkers. CONCLUSIONS: Among PWH, poor CVH as measured by LS7 was associated with coronary plaque presence, vulnerable features, and calcification. LS7 was also associated with selected biomarkers; adjustment for these and ASCVD score reduced but did not eliminate LS7\u27s association with plaque, suggesting the possibility of additional protective mechanisms against atherogenesis and plaque remodeling. Clinical use of LS7 and further exploration of its relationships with coronary artery disease may enhance efforts to reduce cardiovascular morbidity and mortality in PWH. CLINICAL TRIALS REGISTRATION: NCT02344290
    • …
    corecore