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- Dahlqvist, Ake, et al.
(författare)
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Sleep apnea and Down's syndrome
- 2003
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Ingår i: Acta Oto-Laryngologica. - : Taylor & Francis. - 0001-6489 .- 1651-2251. ; 123:9, s. 1094-7
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Obstructive sleep apnea has been reported to occur in 20-50% of children with Down's syndrome in case series of patients referred for evaluation of suspected sleep apnea. In this population-based controlled study, we aimed to investigate whether sleep apnea is related to Down's syndrome.MATERIAL AND METHODS: Every child aged 2-10 years with Down's syndrome residing in the Umeå healthcare district (n = 28) was invited to participate in the study, with their siblings acting as controls. Successful overnight sleep apnea recordings and echocardiography were performed in 17/21 children with Down's syndrome and in 21 controls.RESULTS: Obstructive sleep apnea could not be diagnosed, either in children with Down's syndrome or in the control children. The apnea-hypopnea index in the children with Down's syndrome was 1.2 +/- 1.5 and did not differ from that in controls. Snoring and hypertrophy of the tonsils were more common in children with Down's syndrome than in controls. Children with Down's syndrome slept for a shorter time (p < 0.001) and changed body position more often (p < 0.05) than the control children.CONCLUSIONS: Snoring, restless sleep and hypertrophy of the tonsils were common among children with Down's syndrome. Obstructive sleep apnea was, however, not related to Down's syndrome in the present population-based controlled study.
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| 2. |
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| 3. |
- Rask, Eva, 1958-, et al.
(författare)
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Impaired incretin response after a mixed meal is associated with insulin resistance in nondiabetic men
- 2001
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Ingår i: Diabetes Care. - : American Diabetes Association. - 0149-5992 .- 1935-5548. ; 24:9, s. 1640-1645
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE:To investigate whether features of the insulin resistance syndrome are associated with altered incretin responses to food intake.RESEARCH DESIGN AND METHODS:From a population-based study, 35 men were recruited, representing a wide spectrum of insulin sensitivity and body weight. Each subject underwent a hyperinsulinemic-euglycemic clamp to determine insulin sensitivity. A mixed meal was given, and plasma levels of gastric inhibitory polypeptide (GIP) and glucagon-like peptide 1 (GLP-1), as well as insulin, glucagon, and glucose were measured.RESULTS:Insulin resistance was associated with impaired GIP and GLP-1 responses to a mixed meal. The total area under the curve (AUC) of the GIP response after the mixed meal was associated with insulin sensitivity (r = 0.54, P < 0.01). There was a significant difference between the highest and the lowest tertile of insulin sensitivity (P < 0.05). GLP-1 levels 15 min after food intake were significantly lower in the most insulin-resistant tertile compared with the most insulin-sensitive tertile. During the first hour, the AUC of GLP-1 correlated significantly with insulin sensitivity (r = 0.47, P < 0.01). Multiple linear regression analysis showed that insulin resistance, but not obesity, was an independent predictor of these decreased incretin responses.CONCLUSIONS:In insulin resistance, the GIP and GLP-1 responses to a mixed meal are impaired and are related to the degree of insulin resistance. Decreased incretin responsiveness may be of importance for the development of impaired glucose tolerance.
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| 5. |
- Rask, Eva, 1958-, et al.
(författare)
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Tissue-specific changes in peripheral cortisol metabolism in obese women : increased adipose 11beta-hydroxysteroid dehydrogenase type 1 activity
- 2002
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : Williams & Wilkins Co.. - 0021-972X .- 1945-7197. ; 87:7, s. 3330-6
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Tidskriftsartikel (refereegranskat)abstract
- Cushing's syndrome and the metabolic syndrome share clinical similarities. Reports of alterations in the hypothalamic-pituitary-adrenal (HPA) axis are inconsistent, however, in the metabolic syndrome. Recent data highlight the importance of adipose 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1), which regenerates cortisol from cortisone and, when overexpressed in fat, produces central obesity and glucose intolerance. Here we assessed the HPA axis and 11beta-HSD1 activity in women with moderate obesity and insulin resistance. Forty women were divided into tertiles according to body mass index (BMI; median, 22.0, 27.5, and 31.4, respectively). Serum cortisol levels were measured after iv CRH, low dose dexamethasone suppression, and oral cortisone administration. Urinary cortisol metabolites were measured in a 24-h sample. A sc abdominal fat biopsy was obtained in 14 participants for determination of 11beta-HSD type 1 activity in vitro. Higher BMI was associated with higher total cortisol metabolite excretion (r = 0.49; P < 0.01), mainly due to increased 5alpha- and, to a lesser extent, 5beta-tetrahydrocortisol excretion, but no difference in plasma cortisol basally, after dexamethasone, or after CRH, and only a small increase in the ACTH response to CRH. Hepatic 11beta-HSD1 conversion of oral cortisone to cortisol was impaired in obese women (area under the curve, 147,736 +/- 28,528, 115,903 +/- 26,032, and 90,460 +/- 18,590 nmol/liter.min; P < 0.001). However, 11beta-HSD activity in adipose tissue was positively correlated with BMI (r = 0.55; P < 0.05). In obese females increased reactivation of glucocorticoids in fat may contribute to the characteristics of the metabolic syndrome. Increased inactivation of cortisol in liver may be responsible for compensatory activation of the HPA axis. These alterations in cortisol metabolism may be a basis for novel therapeutic strategies to reduce obesity-related complications.
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| 6. |
- Rask, Eva, 1958-, et al.
(författare)
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Tissue-specific dysregulation of cortisol metabolism in human obesity
- 2001
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : Williams & Wilkins Co.. - 0021-972X .- 1945-7197. ; 86:3, s. 1418-1421
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Tidskriftsartikel (refereegranskat)abstract
- Cortisol has been implicated as a pathophysiological mediator in idiopathic obesity, but circulating cortisol concentrations are not consistently elevated. The tissue-specific responses to cortisol may be influenced as much by local pre-receptor metabolism as by circulating concentrations. For example, in liver and adipose tissue cortisol is regenerated from inactive cortisone by 11 beta -hydroxysteroid dehydrogenase type 1 (11 beta -HSD1). In obese Zucker rats 11 beta -HSD1 activity is reduced in liver but enhanced in adipose tissue. This study addressed whether the same tissue-specific disruption of cortisol metabolism occurs in human obesity. 34 men were recruited from the MONICA population study in Northern Sweden to represent a wide range of body composition and insulin sensitivity. Plasma cortisol was measured at 0830h and 1230h, after overnight low-dose dexamethasone suppression, after intravenous corticotropin releasing hormone (CRH), and after oral cortisone administration. Urinary cortisol metabolites were measured in a 24 h sample. A subcutaneous fat biopsy was obtained from le participants to measure cortisol metabolism in vitro. Higher body mass index was associated with increased total cortisol metabolite excretion (r=0.47, p<0.01), but lower plasma cortisol at 1230 h and after dexamethasone, and no difference in response to CRH. Obese men excreted a greater proportion of glucocorticoid as metabolites of cortisone rather than cortisol (r=0.43, p<0.02), and converted less cortisone to cortisol after oral administration (r=-0.49, p<0.01), suggesting impaired hepatic 11-HSD1 activity. By contrast, in vitro 11 beta -HSD1 activity in subcutaneous adipose tissue was markedly enhanced in obese men (r=0.66, p<0.01). We conclude that in obesity, reactivation of cortisone to cortisol by 11-HSD1 in liver is impaired, so that plasma cortisol levels tend to fall, and there may be a compensatory increase in cortisol secretion mediated by a normally functioning hypothalamic-pituitary-adrenal axis. However, changes in 11 beta -HSD1 are tissue-specific: strikingly enhanced reactivation of cortisone to cortisol in subcutaneous adipose tissue may exacerbate obesity; and it may be beneficial to inhibit this enzyme in adipose tissue in obese patients.
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| 7. |
- Wake, Deborah J, et al.
(författare)
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Local and systemic impact of transcriptional up-regulation of 11beta-hydroxysteroid dehydrogenase type 1 in adipose tissue in human obesity.
- 2003
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 88:8, s. 3983-3988
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Tidskriftsartikel (refereegranskat)abstract
- In idiopathic obesity circulating cortisol levels are not elevated, but high intraadipose cortisol concentrations have been implicated. 11beta-Hydroxysteroid dehydrogenase type 1 (11HSD1) catalyzes the conversion of inactive cortisone to active cortisol, thus amplifying glucocorticoid receptor (GR) activation. In cohorts of men and women, we have shown increased ex vivo 11HSD1 activity in sc adipose tissue associated with in vivo obesity and insulin resistance. Using these biopsies, we have now validated this observation by measuring 11HSD1 and GR mRNA and examined the impact on intraadipose cortisol concentrations, putative glucocorticoid regulated adipose target gene expression (angiotensinogen and leptin), and systemic measurements of cortisol metabolism. From aliquots of sc adipose biopsies from 16 men and 16 women we extracted RNA for real-time PCR and steroids for immunoassays. Adipose 11HSD1 mRNA was closely related to 11HSD1 activity [standardized beta coefficient (SBC) = 0.58; P < 0.01], and both were positively correlated with parameters of obesity (e.g. for BMI, SBC = 0.48; P < 0.05 for activity, and SBC = 0.63; P < 0.01 for mRNA) and insulin sensitivity (log fasting plasma insulin; SBC = 0.44; P < 0.05 for activity, and SBC = 0.33; P = 0.09 for mRNA), but neither correlated with urinary cortisol/cortisone metabolite ratios. Adipose GR-alpha and angiotensinogen mRNA levels were not associated with obesity or insulin resistance, but leptin mRNA was positively related to 11HSD1 activity (SBC = 0.59; P < 0.05) and tended to be associated with parameters of obesity (BMI: SBC = 0.40; P = 0.09), fasting insulin (SBC = 0.65; P < 0.05), and 11HSD1 mRNA (SBC = 0.40; P = 0.15). Intraadipose cortisol (142 +/- 30 nmol/kg) was not related to 11HSD1 activity or expression, but was positively correlated with plasma cortisol. These data confirm that idiopathic obesity is associated with transcriptional up-regulation of 11HSD1 in adipose, which is not detected by conventional in vivo measurements of urinary cortisol metabolites and is not accompanied by dysregulation of GR. Although this may drive a compensatory increase in leptin synthesis, whether it has an adverse effect on intraadipose cortisol concentrations and GR-dependent gene regulation remains to be established.
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