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1.
J Frailty Aging ; 8(3): 154-159, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31237318

RESUMEN

BACKGROUND: Tesamorelin, a growth hormone-releasing hormone analogue, decreases visceral adipose tissue in people living with HIV, however, the effects on skeletal muscle fat and area are unknown. OBJECTIVES: The goals of this exploratory secondary analysis were to determine the effects of tesamorelin on muscle quality (density) and quantity (area). DESIGN: Secondary, exploratory analysis of two previously completed randomized (2:1), clinical trials. SETTING: U.S. and Canadian sites. PARTICIPANTS: People living with HIV and with abdominal obesity. Tesamorelin participants were restricted to responders (visceral adipose tissue decrease ≥8%). INTERVENTION: Tesamorelin or placebo. MEASUREMENTS: Computed tomography scans (at L4-L5) were used to quantify total and lean density (Hounsfield Units, HU) and area (centimeters2) of four trunk muscle groups using a semi-automatic segmentation image analysis program. Differences between muscle area and density before and after 26 weeks of tesamorelin or placebo treatment were compared and linear regression models were adjusted for baseline and treatment arm. RESULTS: Tesamorelin responders (n=193) and placebo (n=148) participants with available images were similar at baseline; most were Caucasian (83%) and male (87%). In models adjusted for baseline differences and treatment arm, tesamorelin was associated with significantly greater increases in density of four truncal muscle groups (coefficient 1.56-4.86 Hounsfield units; all p<0.005), and the lean anterolateral/abdominal and rectus muscles (1.39 and 1.78 Hounsfield units; both p<0.005) compared to placebo. Significant increases were also seen in total area of the rectus and psoas muscles (0.44 and 0.46 centimeters2; p<0.005), and in the lean muscle area of all four truncal muscle groups (0.64-1.08 centimeters2; p<0.005). CONCLUSIONS: Among those with clinically significant decrease in visceral adipose tissue on treatment, tesamorelin was effective in increasing skeletal muscle area and density. Long term effectiveness of tesamorelin among people with and without HIV, and the impact of these changes in daily life should be further studied.


Asunto(s)
Hormona Liberadora de Hormona del Crecimiento/análogos & derivados , Infecciones por VIH/epidemiología , Músculo Esquelético/efectos de los fármacos , Adulto , Canadá/epidemiología , Femenino , Hormona Liberadora de Hormona del Crecimiento/farmacología , Humanos , Masculino
2.
Pediatr Obes ; 9(4): 281-91, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23801526

RESUMEN

BACKGROUND: Obesity is associated with poor fitness and adverse metabolic consequences in children. OBJECTIVE: To investigate how exercise and lifestyle modification may improve fitness and insulin sensitivity in this population. DESIGN AND SUBJECTS: Randomized controlled trial, 21 obese (body mass index ≥ 95% percentile) subjects, ages 10 to 17 years. METHODS: Subjects were given standardized healthful lifestyle advice for 8 weeks. In addition, they were randomized to an in-home supervised exercise intervention (n = 10) or control group (n = 11). MEASUREMENTS: Fasting laboratory studies (insulin, glucose, lipid profile) and assessments of fitness, body composition, skeletal muscle oxidative phosphorylation and intramyocellular lipid content (IMCL), were performed at baseline and study completion. RESULTS: Subjects were 13.0 ± 1.9 (standard deviation) years old, 72% female and 44% non-white. Exercise improved fitness (P = 0.03) and power (P = 0.01), and increased IMCL (P = 0.02). HOMA-IR decreased among all subjects in response to lifestyle modification advice (P = 0.01), regardless of exercise training assignment. In univariate analysis in all subjects, change in cardiovascular fitness was associated with change in HOMA-IR. In exploratory analyses, increased IMCL was associated with greater resting energy expenditure (r = 0.78, P = 0.005) and a decrease in fasting respiratory quotient (r = -0.70, P = 0.02) (n = 11). CONCLUSIONS: Change in fitness was found to be related to change in insulin resistance in response to lifestyle modification and exercise in obese children. IMCL increased with exercise in these obese children, which may reflect greater muscle lipid oxidative capacity.


Asunto(s)
Diabetes Mellitus Tipo 2/prevención & control , Dieta Reductora , Ejercicio Físico , Resistencia a la Insulina , Metabolismo de los Lípidos , Músculo Esquelético/metabolismo , Obesidad Infantil/metabolismo , Aptitud Física , Conducta de Reducción del Riesgo , Adolescente , Biomarcadores/metabolismo , Niño , Femenino , Humanos , Masculino , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/patología , Fosforilación Oxidativa , Cooperación del Paciente , Obesidad Infantil/fisiopatología , Obesidad Infantil/prevención & control , Resistencia Física , Estados Unidos
3.
Pediatr Obes ; 8(1): 52-61, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22961720

RESUMEN

UNLABELLED: What is already known about this subject Circulating concentrations of branched-chain amino acids (BCAAs) can affect carbohydrate metabolism in skeletal muscle, and therefore may alter insulin sensitivity. BCAAs are elevated in adults with diet-induced obesity, and are associated with their future risk of type 2 diabetes even after accounting for baseline clinical risk factors. What this study adds Increased concentrations of BCAAs are already present in young obese children and their metabolomic profiles are consistent with increased BCAA catabolism. Elevations in BCAAs in children are positively associated with insulin resistance measured 18 months later, independent of their initial body mass index. BACKGROUND: Branched-chain amino acid (BCAA) concentrations are elevated in response to overnutrition, and can affect both insulin sensitivity and secretion. Alterations in their metabolism may therefore play a role in the early pathogenesis of type 2 diabetes in overweight children. OBJECTIVE: To determine whether paediatric obesity is associated with elevations in fasting circulating concentrations of BCAAs (isoleucine, leucine and valine), and whether these elevations predict future insulin resistance. METHODS: Sixty-nine healthy subjects, ages 8-18 years, were enrolled as a cross-sectional cohort. A subset of subjects who were pre- or early-pubertal, ages 8-13 years, were enrolled in a prospective longitudinal cohort for 18 months (n = 17 with complete data). RESULTS: Elevations in the concentrations of BCAAs were significantly associated with body mass index (BMI) Z-score (Spearman's Rho 0.27, P = 0.03) in the cross-sectional cohort. In the subset of subjects that followed longitudinally, baseline BCAA concentrations were positively associated with homeostasis model assessment for insulin resistance measured 18 months later after controlling for baseline clinical factors including BMI Z-score, sex and pubertal stage (P = 0.046). CONCLUSIONS: Elevations in the concentrations of circulating BCAAs are significantly associated with obesity in children and adolescents, and may independently predict future insulin resistance.


Asunto(s)
Aminoácidos de Cadena Ramificada/sangre , Trastornos de la Nutrición del Niño/sangre , Diabetes Mellitus Tipo 2/sangre , Resistencia a la Insulina , Insulina/sangre , Obesidad/sangre , Adolescente , Biomarcadores/sangre , Glucemia/metabolismo , Índice de Masa Corporal , Niño , Trastornos de la Nutrición del Niño/epidemiología , Trastornos de la Nutrición del Niño/prevención & control , Estudios Transversales , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/prevención & control , Ayuno/sangre , Femenino , Humanos , Insulina/metabolismo , Secreción de Insulina , Isoleucina/sangre , Leucina/sangre , Estudios Longitudinales , Masculino , Massachusetts/epidemiología , Obesidad/epidemiología , Obesidad/etiología , Obesidad/prevención & control , Valor Predictivo de las Pruebas , Valina/sangre
4.
Growth Horm IGF Res ; 22(3-4): 102-7, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22465725

RESUMEN

CONTEXT: Growth hormone (GH) is known to be nutritionally regulated, but the effect of dietary composition on detailed GH secretion parameters has not previously been comprehensively evaluated. OBJECTIVE: The objective of the study was to determine whether specific macro- and micronutrients are associated with discrete parameters of GH secretion among subjects with wide ranges of body mass index. DESIGN: Detailed macro- and micronutrient intake was assessed by 4-day food records while GH secretion was assessed by standard stimulation testing in 108 men and women in one study (Study 1), and by overnight frequent blood sampling in 12 men in another study (Study 2). RESULTS: Peak stimulated GH was positively associated with vitamin C (r=+0.29; P=0.003), dietary fiber (r=+0.27; P=0.004), arachidic acid (r=+0.25; P=0.008), and behenic acid (r=+0.30; P=0.002) intake in univariate analysis. Controlling for age, gender, race/ethnicity, visceral fat, HOMA-IR, total caloric intake and these four dietary factors in step-wise multivariate modeling, peak GH remained significantly associated with vitamin C and visceral fat (both P<0.05). In addition, vitamin C intake was associated with various parameters of endogenous GH secretion including basal GH secretion (r=+0.95; P<0.0001), GH half-life (r=+.75; P=0.005), total GH production (r=+0.76; P=0.004), GH area-under-the-curve (r=+0.89; P=0.0001), mean log(10) GH pulse area (r=+0.67; P=0.02), and overnight maximum (r=+0.62; P=0.03), nadir (r=+0.97; P<0.0001), and mean GH secretion (r=+0.89; P=0.0001). CONCLUSIONS: These results suggest that certain micronutrients such as vitamin C intake are strongly and uniquely associated with stimulated and endogenous spontaneous GH secretion.


Asunto(s)
Hormona de Crecimiento Humana/metabolismo , Micronutrientes/metabolismo , Adolescente , Adulto , Ácido Ascórbico/metabolismo , Composición Corporal , Índice de Masa Corporal , Ingestión de Energía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oligoelementos/metabolismo
5.
Growth Horm IGF Res ; 21(3): 155-9, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21531600

RESUMEN

OBJECTIVE: Obesity is associated with both reduced growth hormone (GH) and adiponectin. However, the relationship between adiponectin and parameters of endogenous GH secretion remains unknown. The aim of this study was to determine the relationship between total and high molecular weight (HMW) adiponectin and parameters of endogenous pulsatile GH secretion and the effects of tesamorelin, a synthetic GH releasing hormone (GHRH(1-44)), on total and HMW adiponectin. DESIGN: A 2-week interventional study with tesamorelin was conducted at an academic medical center in 13 men with BMI 20-35 kg/m(2). Overnight frequent blood sampling and measurement of total and HMW adiponectin at baseline and after treatment were performed to assess the effects of augmenting endogenous pulsatile GH secretion. RESULTS: Total, but not HMW, adiponectin was positively associated with log(10)Peak GH area (r=+0.73; P=0.005), basal GH secretion (r=+0.67; P=0.01), and total GH production (r=+0.57; P=0.04), but was not associated with the number of secretion events (P=0.85). Two-week treatment with tesamorelin increased endogenous GH release and IGF-1, but neither total (change -0.16±0.64; P=0.40), nor HMW (change +0.03±0.70; P=0.87) adiponectin changed significantly with treatment. Sub-analyses in overweight and obese men yielded similar results. CONCLUSIONS: Our study demonstrates a strong relationship between specific parameters of endogenous GH pulsatility and adiponectin. However, short-term augmentation of GH pulsatility over 2-weeks does not change adiponectin. Therefore, the relationship between GH and adiponectin is most likely mediated by specific covariates related to adiposity or other factors.


Asunto(s)
Adiponectina/sangre , Hormona Liberadora de Hormona del Crecimiento/análogos & derivados , Hormona de Crecimiento Humana/sangre , Adolescente , Adulto , Hormona Liberadora de Hormona del Crecimiento/farmacología , Humanos , Masculino , Persona de Mediana Edad , Obesidad/metabolismo
6.
HIV Med ; 7(4): 268-74, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16630040

RESUMEN

OBJECTIVES: Adipose dysregulation, dyslipidemia, and insulin resistance are hallmarks of HIV-related lipodystrophy. The precise mechanisms behind these disturbances are unknown. In HIV-infected patients, we previously demonstrated a strong relationship between lipodystrophy and levels of adiponectin, an adipose peptide implicated in regulation of glucose and lipid metabolisms. In this study we investigated the effect of HIV on adipocytes, to determine whether HIV can directly infect adipocytes and/or alter the regulation and secretion of the adipocyte-derived hormone adiponectin. METHODS: Human subcutaneous preadipocytes and adipocytes were exposed to HIV-1 under various conditions. Adiponectin was measured in supernatants and cell lysates. RESULTS: Although adipocytes expressed CD4, the major HIV receptor, they could not be infected in vitro. However, exposure to HIV dramatically increased the secretion of adiponectin from human adipocytes, in the absence of infection. This was exacerbated with sustained exposure to HIV in a transwell assay. Further, human peripheral mononuclear cells also produced adiponectin, but this was largely dependent upon T-cell activation. CONCLUSIONS: We propose that the stimulation of adiponectin production by HIV can perturb adiponectin regulation, leading to substantially decreased levels upon viral suppression by antiretroviral therapy. These data suggest a potential molecular mechanism of adiponectin regulation in HIV-infected patients.


Asunto(s)
Adipocitos/fisiología , Adiponectina/fisiología , VIH-1/patogenicidad , Adipocitos/virología , Adipogénesis/fisiología , Adiponectina/análisis , Tejido Adiposo/química , Tejido Adiposo/virología , Animales , Terapia Antirretroviral Altamente Activa/efectos adversos , Linfocitos T CD4-Positivos/química , Infecciones por VIH/diagnóstico , Síndrome de Lipodistrofia Asociada a VIH/fisiopatología , Síndrome de Lipodistrofia Asociada a VIH/virología , Humanos , Interleucina-2/fisiología , Interleucina-6/fisiología , Leucocitos Mononucleares/fisiología , Leucocitos Mononucleares/virología , Ratones , ARN Mensajero/análisis , Receptores del VIH/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Factor de Necrosis Tumoral alfa/fisiología
7.
Am J Physiol Endocrinol Metab ; 290(2): E289-98, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16131513

RESUMEN

Altered fat distribution is associated with insulin resistance in HIV, but little is known about regional glucose metabolism in fat and muscle depots in this patient population. The aim of the present study was to quantify regional fat, muscle, and whole body glucose disposal in HIV-infected men with lipoatrophy. Whole body glucose disposal was determined by hyperinsulinemic clamp technique (80 mU x m(-2) x min(-1)) in 6 HIV-infected men and 5 age/weight-matched healthy volunteers. Regional glucose uptake in muscle and subcutaneous (SAT) and visceral adipose tissue (VAT) was quantified in fasting and insulin-stimulated states using 2-deoxy-[18F]fluoro-D-glucose positron emission tomography. HIV-infected subjects with lipoatrophy had significantly increased glucose uptake into SAT (3.8 +/- 0.4 vs. 2.3 +/- 0.5 micromol x kg tissue(-1) x min(-1), P < 0.05) in the fasted state. Glucose uptake into VAT did not differ between groups. VAT area was inversely related with whole body glucose disposal, insulin sensitivity, and muscle glucose uptake during insulin stimulation. VAT area was highly predictive of whole body glucose disposal (r2 = 0.94, P < 0.0001). This may be mediated by adiponectin, which was significantly associated with VAT area (r = -0.75, P = 0.008), and whole body glucose disposal (r = 0.80, P = 0.003). This is the first study to directly demonstrate increased glucose uptake in subcutaneous fat of lipoatrophic patients, which may partially compensate for loss of SAT. Furthermore, we demonstrate a clear relationship between VAT and glucose metabolism in multiple fat and muscle depots, suggesting the critical importance of this depot in the regulation of glucose and highlighting the significant potential role of adiponectin in this process.


Asunto(s)
Tejido Adiposo/metabolismo , Glucosa/metabolismo , Síndrome de Lipodistrofia Asociada a VIH/metabolismo , Resistencia a la Insulina , Insulina/sangre , Músculo Esquelético/metabolismo , Adulto , Humanos , Masculino , Persona de Mediana Edad
8.
Contraception ; 72(3): 206-11, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16102557

RESUMEN

OBJECTIVE: The effects of long-term triphasic oral contraceptive administration on bone mineral density (BMD) were investigated in premenopausal women with hypothalamic amenorrhea (HA) and osteopenia. METHODS: After completing three 28-day cycles in the double-blind phase of a placebo-controlled trial, women (mean age, 26.7 years) who received norgestimate 180-250 microg/ethinyl estradiol 35 microg (NGM/EE, n = 15) or placebo (n = 12) in the double-blind phase were to receive open-label NGM/EE for 10 additional cycles. RESULTS: For subjects completing > or =10 NGM/EE treatment cycles, mean posteroanterior total lumbar spine BMD (L1-L4) increased from 0.881+/-0.0624 g/cm2 at baseline (last visit prior to NGM/EE) to 0.894+/-0.0654 g/cm2 at final visit (p = .043); no significant changes in hip BMD occurred. Decreases in N-telopeptide, osteocalcin, procollagen type I propeptide and bone-specific alkaline phosphatase levels indicated effects on bone metabolism. CONCLUSIONS: Long-term administration of triphasic NGM/EE to osteopenic women with HA may increase total lumbar spine BMD.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Anticonceptivos Sintéticos Orales/farmacología , Etinilestradiol/farmacología , Norgestrel/análogos & derivados , Absorciometría de Fotón , Adolescente , Adulto , Amenorrea/complicaciones , Biomarcadores/metabolismo , Enfermedades Óseas Metabólicas/complicaciones , Enfermedades Óseas Metabólicas/metabolismo , Anticonceptivos Sintéticos Orales/administración & dosificación , Método Doble Ciego , Etinilestradiol/administración & dosificación , Femenino , Humanos , Enfermedades Hipotalámicas/complicaciones , Vértebras Lumbares/diagnóstico por imagen , Norgestrel/administración & dosificación , Norgestrel/farmacología
9.
J Clin Endocrinol Metab ; 89(9): 4434-8, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15356043

RESUMEN

Anorexia nervosa (AN) is characterized by low weight and self-imposed caloric restriction and leads to severe bone loss. Although amenorrhea due to acquired GnRH deficiency is nearly universal in AN, a subset of patients maintains menses despite low weight. The mechanisms underlying continued GnRH secretion despite low weight in these patients and the impact of gonadal hormone secretion on bone mineral density (BMD) in such eumenorrheic, low-weight patients remain unknown. We hypothesized that 1) eumenorrheic women with AN would have higher body fat and levels of nutritionally dependent hormones, including leptin and IGF-I, than amenorrheic women with AN and comparable body mass index; and 2) BMD would be higher in these women. We also investigated whether the severity of eating disorder symptomatology differed between the groups. We studied 116 women: 1) 42 low-weight women who fulfilled all Diagnostic and Statistical Manual of Mental Disorders (fourth edition) diagnostic criteria for AN, except for amenorrhea; and 2) 74 women with AN and amenorrhea for at least 3 months. The two groups were similar in body mass index (17.1 +/- 0.2 vs. 16.8 +/- 0.2 kg/m(2)), percent ideal body weight (78.2 +/- 0.8% vs. 76.7 +/- 0.8%), duration of eating disorder (70 +/- 13 vs. 59 +/- 9 months), age of menarche (13.2 +/- 0.3 vs. 13.5 +/- 0.2 yr), and exercise (4.5 +/- 1.0 vs. 4.2 +/- 0.5 h/wk). As expected, eumenorrheic patients had a higher mean estradiol level (186.6 +/- 19.0 vs. 59.4 +/- 2.5 nmol/liter; P < 0.0001) than amenorrheic subjects. Mean percent body fat, total body fat mass, and truncal fat were higher in eumenorrheic than amenorrheic patients [20.9 +/- 0.9% vs. 16.7 +/- 0.6% (P = 0.0001); 9.8 +/- 0.5 vs. 7.8 +/- 0.3 kg (P = 0.0009); 3.4 +/- 0.2 vs. 2.7 +/- 0.1 kg (P = 0.006)]. The mean leptin level was higher in the eumenorrheic compared with the amenorrheic group (3.7 +/- 0.3 vs. 2.8 +/- 0.2 ng/ml; P = 0.04). Serum IGF-I levels were also higher in the eumenorrheic than in the amenorrheic group (41.8 +/- 3.7 vs. 30.8 +/- 2.3 nmol/liter; P = 0.02). There were only minor differences in severity of eating disorder symptomatology, as measured by the Eating Disorders Inventory, and where differences were observed, eumenorrheic subjects manifested more severe symptomatology than amenorrheic subjects. Mean BMD at the posterior-anterior and lateral spine were low in both groups, but were higher in patients with eumenorrhea than in those with amenorrhea [posterior-anterior spine T-score, -0.9 +/- 0.1 vs. -1.9 +/- 0.1 (P < 0.0001); lateral spine T-score, -1.2 +/- 0.1 vs. -2.3 +/- 0.2 (P < 0.0001)]. In contrast, preservation of menstrual function was not protective at the total hip (total hip T-score, -0.9 +/- 0.1 vs. -1.1 +/- 0.1; P = 0.27), trochanter, or femoral neck. In summary, patients with eumenorrhea had more body fat and higher serum leptin levels than their amenorrheic counterparts of similar weight. Moreover, reduced bone density was observed in both groups, but was less severe at the spine, but not the hip, in women with undernutrition and preserved menstrual function than in amenorrheic women of similar weight. Therefore, fat mass may be important for preservation of normal menstrual function in severely undernourished women, and this may be in part mediated through leptin secretion. In addition, nutritional intake and normal hormonal function may be independent contributors to maintenance of trabecular bone mass in low-weight women.


Asunto(s)
Amenorrea/fisiopatología , Sistema Hipotálamo-Hipofisario/fisiología , Desnutrición/fisiopatología , Menstruación , Adulto , Anorexia Nerviosa/complicaciones , Anorexia Nerviosa/psicología , Composición Corporal , Índice de Masa Corporal , Densidad Ósea , Estradiol/sangre , Femenino , Humanos , Factor I del Crecimiento Similar a la Insulina/análisis , Leptina/sangre , Leptina/fisiología
10.
J Clin Endocrinol Metab ; 88(8): 3651-6, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12915650

RESUMEN

This multicenter, double-blind, placebo-controlled, randomized study of 45 patients evaluated the short-term effects of an oral contraceptive [Ortho Tri-Cyclen, 180-250 micro g of norgestimate (NGM) and 35 microg of ethinyl estradiol (EE)] on biochemical markers of bone resorption, formation, and osteoprotegerin in young women (mean age +/- SD, 26.5 +/- 6.3 yr) with hypothalamic amenorrhea and osteopenia. Body fat, endocrine, and cognitive function were evaluated as secondary endpoints. Biomarkers of bone metabolism were measured at baseline and after three cycles of NGM/EE or placebo. There were significant decreases in mean values of N-telopeptide [mean (SD), -13.4 (13.4) vs. 1.2 (23.8) nmol bone collagen equivalents (BCE)/mmol creatinine (Cr); P = 0.001] and deoxypyridinoline [-1.2 (2.9) vs. -0.5 (1.5) nmol deoxypyridinoline/mmol Cr; P = 0.021] as well as significant decreases in bone specific alkaline phosphatase [-5.1 (3.5) vs. 0.4 (3.1) ng/ml; P < 0.001], osteocalcin [-5.9 (3.6) vs. -2.9 (3.7); P = 0.016], and procollagen of type I propeptide [-35.2 (44.6) vs. -0.2 (30.0) ng/ml; P = 0.025], but not osteoprotegerin [0.39 (1.46) vs. -0.2 (0.49) pmol/liter; P = 0.397] in the NGM/EE vs. placebo group. There were no significant differences between groups with respect to changes in cognitive function, mood, body weight, body mass index, body fat, percentage of body fat, and all endocrine levels except FSH, [-3.7 (3.8) vs. -0.6 (2.1) IU/liter; P < 0.001, NGM/EE vs. placebo]. No serious adverse events were reported in either group. These results suggest that NGM/EE decreases bone turnover in osteopenic premenopausal women with hypothalamic amenorrhea. Further studies are needed to determine whether estrogen will increase bone density in this population.


Asunto(s)
Amenorrea/complicaciones , Enfermedades Óseas Metabólicas/tratamiento farmacológico , Enfermedades Óseas Metabólicas/etiología , Huesos/metabolismo , Anticonceptivos Orales Combinados/uso terapéutico , Etinilestradiol/uso terapéutico , Enfermedades Hipotalámicas/complicaciones , Norgestrel/análogos & derivados , Norgestrel/uso terapéutico , Adolescente , Adulto , Amenorrea/metabolismo , Biomarcadores , Enfermedades Óseas Metabólicas/metabolismo , Resorción Ósea/metabolismo , Huesos/efectos de los fármacos , Cognición/efectos de los fármacos , Anticonceptivos Orales Combinados/efectos adversos , Método Doble Ciego , Etinilestradiol/efectos adversos , Femenino , Hormonas Esteroides Gonadales/sangre , Humanos , Enfermedades Hipotalámicas/metabolismo , Norgestrel/efectos adversos
11.
Trends Endocrinol Metab ; 12(9): 413-9, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11595544

RESUMEN

Insulin resistance is increasingly recognized among HIV-infected patients with fat redistribution (lipodystrophy) who are receiving highly active antiretroviral therapy. The mechanisms of insulin resistance in this population remain unknown, but could relate to a decrease in glucose transport caused by the direct effects of certain antiretroviral agents, such as the protease inhibitors, or to the effects of severe fat redistribution, including subcutaneous fat loss and increased visceral adiposity. Insulin resistance in patients with HIV lipodystrophy is associated with hyperlipidemia and impaired fibrinolysis, and might increase the risk of cardiovascular disease (CVD). Furthermore, insulin-sensitizing agents might improve insulin resistance and reduce the risk of CVD in this population.


Asunto(s)
Infecciones por VIH/complicaciones , Resistencia a la Insulina , Lipodistrofia/fisiopatología , Lipodistrofia/virología , Humanos , Síndrome
12.
J Clin Endocrinol Metab ; 86(9): 4120-6, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11549636

RESUMEN

Although prior studies suggest reduced androgen levels in women with acquired immune deficiency syndrome wasting, little is known regarding the regulation of adrenal and ovarian androgen secretion in such patients. We investigated ovarian and adrenal function in 13 human immunodeficiency virus-infected women with acquired immune deficiency syndrome wasting and 21 age- and body mass index-matched healthy control subjects studied in the early follicular phase. Subjects received hCG (5000 U, im) on d 1 and Cosyntropin (0.25 mg, i.v.) on d 3 after dexamethasone (1 mg, orally, at 2400 h) pretreatment on d 2. At baseline, human immunodeficiency virus-infected subjects demonstrated significantly reduced T [18 +/- 2 vs. 25 +/- 2 ng/dl (0.6 +/- 0.1 vs. 0.9 +/- 0.1 nmol/liter); P = 0.02], free T [1.5 +/- 0.1 vs. 2.4 +/- 0.2 pg/ml (5.3 +/- 0.5 vs. 8.3 +/- 0.6 pmol/liter); P = 0.001], androstenedione [119 +/- 6 vs. 162 +/- 14 ng/dl (4.16 +/- 0.20 vs. 5.66 +/- 0.48 nmol/liter); P = 0.02], and dehydroepiandrosterone sulfate [0.96 +/- 0.17 vs. 1.55 +/- 0.19 microg/ml (2.6 +/- 0.5 vs. 4.2 +/- 0.5 micromol/liter); P = 0.047] levels compared with the control subjects. T [8 +/- 2 vs. 6 +/- 2 ng/dl (0.3 +/- 0.1 vs. 0.2 +/- 0.1 nmol/liter); P = 0.48], free T [0.5 +/- 0.2 vs. 0.4 +/- 0.1 pg/ml (1.7 +/- 0.7 vs. 1.5 +/- 0.5 pmol/liter); P = 0.85], 17 hydroxyprogesterone [0.5 +/- 0.2 vs. 0.7 +/- 0.2 microg/liter (1.6 +/- 0.6 vs. 2.0 +/- 0.6 nmol/liter); P = 0.63], and androstenedione [-1 +/- 12 vs. 8 +/- 11 ng/dl (-0.03 +/- 0.42 vs. 0.28 +/- 0.39 nmol/liter), P = 0.61] responses to hCG were not different between the groups. Cortisol responses were increased and dehydroepiandrosterone sulfate responses were decreased in the human immunodeficiency virus-infected vs. control subjects after ACTH stimulation. The ratio of DHEA to cortisol was significantly decreased at 60 (71 +/- 11 vs. 107 +/- 10; P = 0.02) and 90 (63 +/- 8 vs. 102 +/- 9; P = 0.004) min post-ACTH in the human immunodeficiency virus-infected patients compared with control subjects. Baseline urinary free cortisol levels were not different between the groups [36 +/- 9 vs. 36 +/- 5 microg/24 h (99 +/- 26 vs. 100 +/- 13 nmol/d)]. The DHEA to cortisol ratio correlated with the CD4 count (r = 0.67; P = 0.01). These data demonstrate significant shunting of adrenal steroid metabolism away from androgenic pathways and toward cortisol production in human immunodeficiency virus-infected women with the wasting syndrome. In contrast, our data suggest intact ovarian androgen responsivity to hCG stimulation. Further studies of the mechanism of adrenal steroid shunting and the efficacy of androgen replacement in human immunodeficiency virus-infected women are necessary.


Asunto(s)
Andrógenos/deficiencia , Infecciones por VIH/sangre , Síndrome de Emaciación por VIH/sangre , Glándulas Suprarrenales/fisiopatología , Adulto , Andrógenos/sangre , Área Bajo la Curva , Peso Corporal/fisiología , Recuento de Linfocito CD4 , Gonadotropina Coriónica/farmacología , Cosintropina , Sulfato de Deshidroepiandrosterona/sangre , Ingestión de Energía/fisiología , Femenino , Infecciones por VIH/fisiopatología , Síndrome de Emaciación por VIH/fisiopatología , Humanos , Ovario/fisiopatología
13.
Clin Infect Dis ; 33(6): 857-64, 2001 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-11512091

RESUMEN

Androgen deficiency is a common endocrine abnormality among men and women with human immunodeficiency virus (HIV) infection. Low testosterone concentrations are associated with lower CD4 cell count, advanced stage of illness, medication use, and weight loss. Signs and symptoms may be nonspecific. The most useful laboratory indicator is the serum bioavailable (free) testosterone concentration. A number of different testosterone preparations for treatment of androgen deficiency in HIV-infected men now exist. Administration of im testosterone significantly increases weight and lean body mass, energy, quality of life, and depression scores in HIV-infected men with low testosterone levels. Newer transdermal and gel preparations provide more-consistent steady-state dosing but are not as well tested, and sufficient testosterone concentrations may not be achieved with their use. Androgen deficiency is also common among HIV-infected women. Preliminary studies suggest that use of physiological testosterone administration, to achieve testosterone levels within the normal range, is of benefit in HIV-infected women, but further studies are necessary to define the therapeutic role of androgen therapy in this population.


Asunto(s)
Andrógenos/deficiencia , Infecciones por VIH/metabolismo , Andrógenos/fisiología , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Humanos , Hipogonadismo/tratamiento farmacológico , Hipogonadismo/etiología , Hipogonadismo/metabolismo , Masculino , Caracteres Sexuales , Testosterona/administración & dosificación , Testosterona/sangre , Testosterona/deficiencia
15.
J Clin Endocrinol Metab ; 86(8): 3533-9, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11502775

RESUMEN

Women with acquired immune deficiency syndrome wasting are at an increased risk of osteopenia because of low weight, changes in body composition, and hormonal alterations. Although women comprise an increasing proportion of human immunodeficiency virus-infected patients, prior studies have not investigated bone loss in this expanding population of patients. In this study we investigated bone density, bone turnover, and hormonal parameters in 28 women with acquired immune deficiency syndrome wasting and relative androgen deficiency (defined as free testosterone < or =3.0 pg/ml, weight < or =90% ideal body weight, weight loss > or =10% from preillness maximum weight, or weight <100% ideal body weight with weight loss > or =5% from preillness maximum weight). Total body (1.04 +/- 0.08 vs. 1.10 +/- 0.07 g/cm2, human immunodeficiency virus-infected vs. control respectively; P < 0.01), anteroposterior lumbar spine (0.94 +/- 0.12 vs. 1.03 +/- 0.09 g/cm2; P = 0.005), lateral lumbar spine (0.71 +/- 0.14 vs. 0.79 +/- 0.09 g/cm2; P = 0.02), and hip (Ward's triangle; 0.68 +/- 0.14 vs. 0.76 +/- 0.12 g/cm2; P = 0.05) bone density were reduced in the human immunodeficiency virus-infected compared with control subjects. Serum N-telopeptide, a measure of bone resorption, was increased in human immunodeficiency virus-infected patients, compared with control subjects (14.6 +/- 5.8 vs. 11.3 +/- 3.8 nmol/liter bone collagen equivalents, human immunodeficiency virus-infected vs. control respectively; P = 0.03). Although body mass index was similar between the groups, muscle mass was significantly reduced in the human immunodeficiency virus-infected vs. control subjects (16 +/- 4 vs. 21 +/- 4 kg, human immunodeficiency virus-infected vs. control, respectively; P < 0.0001). In univariate regression analysis, muscle mass (r = 0.53; P = 0.004) and estrogen (r = 0.51; P = 0.008), but not free testosterone (r = -0.05, P = 0.81), were strongly associated with lumbar spine bone density in the human immunodeficiency virus-infected patients. The association between muscle mass and bone density remained significant, controlling for body mass index, hormonal status, and age (P = 0.048) in multivariate regression analysis. These data indicate that both hormonal and body composition factors contribute to reduced bone density in women with acquired immune deficiency syndrome wasting. Anabolic strategies to increase muscle mass may be useful to increase bone density among osteopenic women with acquired immune deficiency syndrome wasting.


Asunto(s)
Andrógenos/deficiencia , Densidad Ósea , Síndrome de Emaciación por VIH/fisiopatología , Testosterona/sangre , Absorciometría de Fotón , Tejido Adiposo/anatomía & histología , Adulto , Análisis de Varianza , Biomarcadores/sangre , Índice de Masa Corporal , Peso Corporal , Resorción Ósea , Colágeno/análisis , Colágeno/sangre , Colágeno Tipo I , Estrógenos/sangre , Femenino , Síndrome de Emaciación por VIH/sangre , Humanos , Análisis Multivariante , Músculo Esquelético/anatomía & histología , Péptidos/sangre , Valores de Referencia , Análisis de Regresión , Pérdida de Peso
16.
Clin Infect Dis ; 33(5): 710-7, 2001 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-11486294

RESUMEN

We assessed the relationship between dietary intake, body composition, and metabolic parameters in 85 consecutive human immunodeficiency virus (HIV)-infected patients with fat redistribution. Dietary history and values for fasting glucose, insulin, lipids, and oral glucose tolerance were obtained for 62 men and 23 women with HIV infection and fat redistribution (mean age +/- standard error of the mean [SEM], 43.5+/-0.9 years; mean body mass index [BMI] +/- SEM, 26.3+/-0.5 kg/m2). A multivariate regression analysis was used to predict insulin area under the curve (AUC) following the oral glucose tolerance test; this included age, sex, BMI, waist-to-hip ratio, kilocalories, duration of protease inhibitor (PI) use, fat redistribution pattern, alcohol intake, dietary fiber intake, and polyunsaturated-to-saturated (P:S) fat ratio. Only age (P=.004), PI use duration (P=.02), and P:S fat ratio (P=.003) were positively associated with insulin AUC. Dietary fiber intake was inversely associated with the insulin AUC (P=.001). In a similar analysis, alcohol consumption was a significant positive predictor of low-density lipoprotein cholesterol. Polyunsaturated fats, fiber, and alcohol are strongly associated with insulin resistance and hyperlipidemia in this population and may be important targets for dietary modification.


Asunto(s)
Tejido Adiposo/patología , Conducta Alimentaria , Infecciones por VIH/dietoterapia , Infecciones por VIH/metabolismo , Tejido Adiposo/metabolismo , Adulto , Consumo de Bebidas Alcohólicas/metabolismo , Composición Corporal , Índice de Masa Corporal , Estudios de Casos y Controles , Ingestión de Energía , Femenino , Glucosa/metabolismo , Infecciones por VIH/patología , Humanos , Insulina/metabolismo , Metabolismo de los Lípidos , Masculino
17.
AIDS ; 15(8): 975-82, 2001 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-11399979

RESUMEN

OBJECTIVE: To examine the relationship between bone density and changes in regional and whole body composition in HIV-infected men with and without lipodystrophy. DESIGN: Cross-sectional, observational study of HIV-infected men with and without lipodystrophy and matched HIV-negative controls. SETTING: Tertiary care academic medical institution. PATIENTS: A total of 59 men, belonging to three different groups: HIV-positive men with lipodystrophy (n = 21), HIV-positive men without lipodystrophy (n = 20), and age-matched and body mass index-matched HIV-negative controls (n = 18). METHODS: Bone density, markers of bone turnover and indices of calcium metabolism were measured in all subjects. Quantitative computed tomography was used both to determine volumetric bone density of the spine and to quantify abdominal visceral fat. Dual energy X-ray absorptiometry was used to determine whole body composition and bone density. Statistical comparisons were performed according to lipodystrophy categorization and protease inhibitor exposure. RESULTS: Men with HIV-associated lipodystrophy had reduced lumbar spine bone density compared with both HIV-infected non-lipodystrophic men [mean +/- SD, 132 +/- 29 versus 154 +/- 30 mg/cm(3); P = 0.02] and HIV-negative controls [mean +/- SD 132 +/- 29 versus 148 +/- 18) mg/cm(3); P = 0.04]. Lumbar spine bone density was reduced significantly in HIV lipodystrophy patients independently of protease inhibitor use. In an analysis among all HIV-infected subjects, increased visceral abdominal fat area was associated with decreased lumbar spine bone density (r, -0.47; P = 0.002). The association between visceral fat and bone density remained significant (P = 0.007) after controlling for age, body mass index, lowest body weight, protease inhibitor use, and extremity fat in a multivariate regression model. Markers of bone turnover were not related to bone density or lipodystrophy status. CONCLUSIONS: Lumbar spine bone density is reduced in association with increased visceral fat in HIV-infected men with lipodystrophy. Further studies are needed to determine the mechanisms of osteopenia in HIV lipodystrophy and whether increased marrow fat occurs in such patients and affects bone density.


Asunto(s)
Tejido Adiposo/patología , Densidad Ósea , Infecciones por VIH/patología , Lipodistrofia/patología , Absorciometría de Fotón , Adulto , Antropometría , Composición Corporal , Estudios Transversales , Infecciones por VIH/tratamiento farmacológico , Inhibidores de la Proteasa del VIH/efectos adversos , Inhibidores de la Proteasa del VIH/uso terapéutico , Humanos , Lipodistrofia/inducido químicamente , Vértebras Lumbares/patología , Masculino , Persona de Mediana Edad , Análisis Multivariante , Análisis de Regresión , Tomografía Computarizada por Rayos X
18.
J Clin Endocrinol Metab ; 86(5): 2020-6, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11344201

RESUMEN

Multiple endocrine and metabolic consequences of human immunodeficiency virus (HIV) infection exist that may contribute to bone loss in men with the acquired immune deficiency syndrome (AIDS) wasting syndrome. Recent studies suggest that anabolic strategies can increase lean body mass in men with AIDS wasting. Prior studies have not examined the effects of anabolic agents on bone mineral density (BMD) or bone turnover in these men. To determine the effects of testosterone and progressive resistance training on BMD and bone turnover in eugonadal men with AIDS wasting, we randomly assigned 54 eugonadal men with AIDS wasting (weight < 90% IBW or weight loss >10% from preillness baseline) to receive either testosterone enanthate (200 mg/week, im) or placebo and to progressive resistance training (3 times/week) or no training in a 2 x 2 factorial study design for 3 months. The BMD of the lumbar spine, proximal femur, and total body; lean body mass; and fat mass were measured by dual energy x-ray absorptiometry. Total body scans were repeated after 12 weeks of therapy. Baseline bone turnover and BMD were compared with those in 35 age-matched healthy non-HIV-infected control subjects. Compared with controls, lumbar spine BMD (1.021 +/- 0.018 vs. 1.084 +/- 0.025 g/cm(2); P = 0.04) and total hip BMD (0.951 +/- 0.017 vs. 1.070 +/- 0.019 g/cm(2); P < 0.0001) were reduced in men with AIDS wasting. T-scores were lower in men with AIDS wasting at the lumbar spine (-0.62 +/- 0.17 vs. -0.07 +/- 0.23, P = 0.05) and total hip (-0.65 +/- 0.11 vs. +0.20 +/- 0.014, P < 0.0001). Total hip T scores were less than -1.0 in 33% of men with AIDS wasting. Neither the use of protease inhibitors nor the duration of protease inhibitors use correlated with BMD. Serum osteocalcin levels were lower (3.63 +/- 0.29 vs. 4.54 +/- 0.31 nmol/L; P < 0.04) and urinary N-telopeptide excretion was higher (45.4 +/- 4.5 vs. 26.8 +/- 3.0 nmol BCE/mmol creatinine; P = 0.004) in men with AIDS wasting than in controls. Lumbar spine BMD, as assessed on regional total body dual energy x-ray absorptiometry scan, increased over the 12-week treatment period in response to testosterone (+2.4 +/- 1.3 vs. -1.3 +/- 1.0%, testosterone vs. placebo, respectively; P = 0.02), but not in response to training (+0.8 +/- 1.0 vs. +0.4 +/- 1.3%, training vs. no training; P = 0.70). Lumbar spine and total hip BMD are reduced in eugonadal men with AIDS wasting. Biochemical markers of bone turnover suggest that bone formation and bone resorption are uncoupled in these men. Testosterone administration, but not resistance training, over 3 months increases lumbar spine BMD in eugonadal men with AIDS wasting.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Enfermedades Óseas Metabólicas/etiología , Síndrome de Emaciación por VIH/metabolismo , Hipogonadismo/metabolismo , Testosterona/uso terapéutico , Humanos , Masculino , Inhibidores de Proteasas/farmacología
19.
J Appl Physiol (1985) ; 90(6): 2166-71, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11356779

RESUMEN

Loss of lean body and muscle mass characterizes the acquired immunodeficiency syndrome (AIDS) wasting syndrome (AWS). Testosterone and exercise increase muscle mass in men with AWS, with unclear effects on muscle composition. We examined muscle composition in 54 eugonadal men with AWS who were randomized to 1) testosterone (200 mg im weekly) or placebo and simultaneously to 2) resistance training or no training in a 2 x 2 factorial design. At baseline and after 12 wk, we performed assessments of whole body composition by dual-energy X-ray absorptiometry and single-slice computed tomography for midthigh cross-sectional area and muscle composition. Leaner muscle has greater attenuation. Baseline muscle attenuation correlated inversely with whole body fat mass (r = -0.52, P = 0.0001). This relationship persisted in a model including age, body mass index, testosterone level, viral load, lean body mass, and thigh muscle cross-sectional area (P = 0.02). Testosterone (P = 0.03) and training (P = 0.03) increased muscle attenuation. These data demonstrate that thigh muscle attenuation by computed tomography varies inversely with whole body fat and increases with testosterone and training. Anabolic therapy in these patients increases muscle leanness.


Asunto(s)
Ejercicio Físico/fisiología , Síndrome de Emaciación por VIH/patología , Síndrome de Emaciación por VIH/terapia , Músculo Esquelético/patología , Testosterona/uso terapéutico , Adulto , Composición Corporal/fisiología , Síndrome de Emaciación por VIH/tratamiento farmacológico , Humanos , Masculino , Músculo Esquelético/metabolismo , Aptitud Física , Testosterona/metabolismo , Tomografía Computarizada por Rayos X
20.
Am J Clin Nutr ; 73(5): 865-9, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11333838

RESUMEN

BACKGROUND: Anorexia nervosa is a disease of severe acquired undernutrition with a high and increasing prevalence among young women in the United States. OBJECTIVE: The objective was to investigate the effects of spontaneous outpatient weight recovery and estrogen administration on fat distribution in patients with anorexia nervosa. DESIGN: Twenty-seven amenorrheic women aged 26.6 +/- 1.2 y with anorexia nervosa were identified through an outpatient study of bone loss and were randomly assigned to receive or not receive estrogen without any dietary intervention other than calcium and multivitamin supplements. Body composition was measured at baseline and at 6 and 9 mo and was compared with cross-sectional values obtained in 20 healthy, eumenorrheic, age-matched (25.4 +/- 0.5 y) control subjects. RESULTS: Twenty of the 27 patients with anorexia aged 27.0 +/- 1.3 y spontaneously gained weight (4.1 +/- 0.9 kg); body mass index (in kg/m(2)) increased from 16.1 +/- 0.3 to 17.5 +/- 0.4. Fat mass and lean mass accounted for 68% and 32% of the gain in total body mass, respectively. With spontaneous weight gain, there was a significant increase in the percentage of trunk fat from 32.4 +/- 1.3% at baseline to 36.5 +/- 1.0% at 9 mo (P = 0.03), which correlated with urinary free cortisol (r = 0.66, P = 0.003). Estrogen treatment was not protective against the gain in trunk fat with spontaneous weight gain. CONCLUSIONS: In women with anorexia nervosa, spontaneous weight gain is associated with a significant increase in trunk adiposity, and estrogen administration may not protect against the accumulation of central fat with weight gain.


Asunto(s)
Tejido Adiposo/anatomía & histología , Anorexia Nerviosa/tratamiento farmacológico , Anorexia Nerviosa/fisiopatología , Anticonceptivos Orales Combinados/uso terapéutico , Aumento de Peso/fisiología , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/fisiopatología , Adulto , Composición Corporal/efectos de los fármacos , Composición Corporal/fisiología , Índice de Masa Corporal , Calcio/uso terapéutico , Suplementos Dietéticos , Etinilestradiol/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Hidrocortisona/sangre , Noretindrona/uso terapéutico , Factores de Tiempo , Vitaminas/uso terapéutico , Aumento de Peso/efectos de los fármacos
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