| 1. |
- Ljung, Thomas, 1961-, et al.
(author)
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Inhibition of cortisol secretion by dexamethasone in relation to body fat distribution: a dose-response study
- 1996
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In: Obesity Research. - : Wiley. - 1071-7323 .- 1550-8528. ; 4:3, s. 277-282
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Journal article (peer-reviewed)abstract
- There is now evidence of a hypersensitive hypothalamo-pituitary-adrenal (RPA) axis in subjects with an elevated waist/hip circumference ratio (WHR), an indicator of the centralization of body fat stores. The activity of the HPA axis is regulated by central glucocorticoid receptors, whose activity can be tested by the administration of exogenous glucocorticoids, which normally inhibit cortisol secretion.In this study, dexamethasone (dex) was administered in random order in doses of 0.05, 0.125, 0.25 and 0.5 mg at 10 p.m. with measurements of serum cortisol in the morning (8 a.m.) of this and the following day. The test was performed on 22 apparently healthy men, 40 to 60 years of age, recruited from laboratory personnel, outpatient clinics or advertisements in a newspaper. Eight had a body mass index (BMI) (kg/m(2)) of <25 and 14 of >25. Twelve men had a waist hip ratio (WHR) of <1.0 and 10 men had a WHR of >1.0.Cortisol values at baseline were correlated inversely with WHR and were usually lower in men with a high (>1.0) rather than a low than low (<1.0) WHR after dex inhibition. There was apparently no inhibition by dex at 0.05 and 0.125 mg on average in men with a WHR of >1.0. In addition, the inhibition at 0.5 mg dex correlated negatively with the WHR and was significantly lower (p<0.05) in men with a WHR of >1.0 than in men with a WHR of <1.0. None of these differences or relationships was found to be dependent on BMI.It is concluded that men with an elevated WHR experience a decrease in the inhibition of cortisol secretion by dex. It is suggested that this could explain or contribute to the elevated sensitivity of their HPA axis. Furthermore, lower morning cortisol concentrations suggest a change in diurnal secretion patterns.
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| 2. |
- Oscarsson, Jan, 1960, et al.
(author)
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Low dose continuously infused growth hormone results in increased lipoprotein(a) and decreased low density lipoprotein cholesterol concentrations in middle-aged men.
- 1994
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In: Clinical endocrinology. - 0300-0664. ; 41:1, s. 109-16
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Journal article (peer-reviewed)abstract
- Animal studies have shown that slight increases in basal GH concentrations may result in changes in lipoprotein metabolism. Such changes in GH secretion have been observed in physiological and pathophysiological states such as fasting, uncontrolled diabetes and during oestrogen treatment. The aim of this study was to investigate the possible effects of increases in basal plasma GH concentrations on lipoprotein concentrations.Recombinant human growth hormone (rhGH) was given as a continuous subcutaneous infusion in a low dose (0.02 U/kg/day) in an open study.Eight middle-aged (42-59 years) overweight (body mass index: 26.1-33.8 kg/m2) but otherwise healthy men were studied over a period of 14 days.Blood samples were obtained after an over-night fast before and after 2, 7 and 14 days of treatment. Plasma and serum were separated and used for subsequent measurements of hormone and lipoprotein concentrations. On days 0, 7 and 14 of treatment, post-heparin plasma was also obtained for determinations of plasma lipoprotein lipase and hepatic lipase activities. In addition, a hyperinsulinaemic euglycaemic glucose clamp was performed on days 0 and 13 of the study. Fat biopsies from abdominal and gluteal fat depots were obtained for measurement of lipoprotein lipase activities on days 0 and 14 of the study.Serum GH concentrations increased to a steady level of 2-4 mU/l during treatment. Serum insulin-like growth factor-I (IGF-I) concentrations increased throughout the treatment period to twice the pretreatment levels. Plasma insulin and blood glucose concentrations increased on day 2 of treatment. After 7 and 14 days of treatment blood glucose concentrations were not different from pretreatment levels, but plasma insulin concentrations were still elevated. Serum cholesterol and low density lipoprotein (LDL) cholesterol concentrations had decreased after 7 and 14 days of treatment. High density lipoprotein (HDL) cholesterol concentrations were not affected, but very low density lipoprotein (VLDL) cholesterol and triglyceride concentrations increased transiently at day 2 of treatment. Serum apolipoprotein (apo) A-I, apoB and apoE concentrations were not significantly affected. Serum lipoprotein(a) concentrations had increased by days 7 and 14 to 147 and 142% of pretreatment concentrations, respectively. Lipoprotein lipase and hepatic lipase activities in post-heparin plasma, as well as abdominal and gluteal adipose tissue lipoprotein lipase activities, were not affected. There was no significant change in glucose disposal rate estimated from the glucose clamp studies.A low dose infusion of GH results in marked changes in lipoprotein concentrations with a transient increase in VLDL cholesterol and thereafter in a decrease in LDL cholesterol. In addition, this low dose of GH resulted in marked increases in lipoprotein(a) concentrations. The observed effects of GH may partly involve changes in IGF-I and insulin secretion.
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| 3. |
- Ottosson, Malin, 1959, et al.
(author)
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Blockade of the glucocorticoid receptor with RU 486: effects in vitro and in vivo on human adipose tissue lipoprotein lipase activity.
- 1995
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In: Obesity research. - 1071-7323. ; 3:3, s. 233-40
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Journal article (peer-reviewed)abstract
- Cortisol is known to induce lipoprotein lipase (LPL) activity in human adipose tissue in vitro and in vivo such as in Cushing's syndrome. The significance of the glucocorticoid receptor (GR) for this induction was evaluated in the present study. The synthetic steroid molecule RU 486, a potent glucocorticoid antagonist, was used as a tool to block the GR, in vitro and in vivo. In addition to LPL activity, glucose tolerance, blood pressure and plasma lipids, all variables influenced by cortisol, were studied in order to evaluate the peripheral antiglucocorticoid activity of RU 486 in vivo, in man. Addition of both cortisol and RU 486 to incubations of human adipose tissue pieces significantly inhibited the increase in LPL activity that could be induced by cortisol alone (p < 0.01). In a ten-fold molarity excess RU 486 totally abolished cortisol action (p < 0.01). With cortisol and RU 486 in equimolar concentrations the RU 486 blockade was probably incomplete and LPL activity induced (p < 0.05). The results imply that the stimulating effect of cortisol on LPL activity in human adipose tissue is mediated via the GR. Administration of 400 mg RU 486 at 2200 hours on two consecutive days to healthy men caused a significant rise in serum cortisol levels measured at 0800 hours (p < 0.05). The mean LPL activity in the subcutaneous abdominal adipose tissue remained unchanged. The mean level of serum triglycerides decreased significantly (p < 0.01) and there was a negative correlation between change in LPL activity and change in triglyceride levels (r = -0.73, p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
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| 4. |
- Andersson, B., et al.
(author)
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Testosterone concentrations in women and men with NIDDM
- 1994
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In: Diabetes Care. ; 17, s. 405-411
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Journal article (peer-reviewed)abstract
- Department of Medicine, Sahlgren's Hospital, University of Göteborg, Sweden. OBJECTIVE--To evaluate androgen concentrations in relation to insulin resistance in men and women with and without NIDDM. Recent studies have indicated the potential importance of the regulation of insulin sensitivity by androgens in both women and men. Low sex hormone binding globulin (SHBG) concentration is an independent risk factor for the development of non-insulin-dependent diabetes mellitus (NIDDM) in women and is strongly associated statistically with signs of insulin resistance. RESEARCH DESIGN AND METHODS--We compared measurements of anthropometric variables and SHBG, steroid hormone, and insulin concentrations of women and men who have NIDDM with those of control subjects. RESULTS--Women with NIDDM had somewhat higher plasma insulin concentrations, lower SHBG, and higher free testosterone values than did control subjects with similar body mass index (BMI). Women with NIDDM had marginally higher waist-to-hip ratios (WHR). Plasma insulin concentrations correlated positively with BMI, WHR, and free testosterone and negatively with SHBG. In multivariate analyses, insulin concentrations remained positively associated with BMI and free testosterone. Men with NIDDM had higher fasting plasma insulin concentrations than did the nondiabetic control subjects. Testosterone and SHBG were lower in the diabetic men than in both control groups. The derived value of free testosterone was not different between groups. Univariate correlation analyses revealed tight statistical couplings between plasma insulin on the one hand and SHBG and testosterone concentrations (negative) on the other. In multivariate analyses, only the insulin-testosterone association remained. CONCLUSIONS: Women with NIDDM have high levels of free testosterone and low levels of SHBG. Insulin resistance is closely correlated with these signs of hyperandrogenicity as well as with obesity. Men with NIDDM also have low levels of SHBG and, in contrast to women, low testosterone values. Insulin values correlate negatively with these hormonal factors. Based on the results of experimental work and intervention studies, we suggest that these androgen abnormalities might be causally related to insulin resistance in NIDDM. PMID: 8062607 [PubMed - indexed for MEDLINE]
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| 5. |
- Andersson, Björn, et al.
(author)
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Urinary albumin excretion and heart rate variability in obese women
- 1998
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In: International Journal of Obesity. - : Springer Science and Business Media LLC. - 0307-0565 .- 1476-5497. ; 22:5, s. 399-405
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Journal article (peer-reviewed)abstract
- OBJECTIVE: The aim of this work was to examine the relationship between cardiac autonomic function and urinary albumin excretion in obesity.SUBJECTS: These were 27 obese non-diabetic postmenopausal women and 18 non-obese healthy postmenopausal women.MEASUREMENTS: Urinary albumin excretion as well as plasma nitrate, both indices of capillary function, were measured. Power spectral analysis of heart rate variability was performed, as a measurement of vagal function. An oral glucose tolerance test (OGTT) was performed and blood lipids were analysed.RESULTS: The obese women were characterized by higher fasting insulin, sum of glucose, triglycerides and lower high density lipoprotein cholesterol (HDL), the latter of borderline significance, than controls. Urinary albumin excretion (UAE), plasma nitrate and heart rate variability were not different between obese and control women. However, in obese women log UAE correlated positively with systolic and diastolic blood pressure, and inversely with heart rate variability, the latter independent of body mass index (BMI) and the waist/hip circumference ratio.CONCLUSION: It was concluded that this inverse association between UAE and parasympathetic activity in obese women may be an early sign of derangements of endothelial function and autonomic nervous system control, which may contribute to the increased risk of cardiovascular mortality in abdominal obesity.
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| 6. |
- Baghaei, Fariba, 1964, et al.
(author)
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Phenotypic and genotypic characteristics of women in relation to personality traits.
- 2003
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In: International journal of behavioral medicine. - 1070-5503. ; 10:4, s. 365-78
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Journal article (peer-reviewed)abstract
- The associations were examined in women between personality traits and steroid hormones, particularly androgens, as well as polymorphisms in genes regulating androgen concentration and effects. Women, all 42 years of age and premenopausal (n = 270), were recruited randomly. Conventional "masculine" and "feminine" personality traits were examined by questionnaire and set in relation to psychosocial and socioeconomic conditions, behavior in childhood, hormones, risk factors for disease, and polymorphisms in microsatellites in the CYP aromatase and the androgen receptor gene. The proportions of personality traits considered as being dominated by "masculinity" (M) or "femininity" (F) were 44.9%, respectively 15.0%, the rest consisting of a combination of M and F (33.2%) or "undifferentiated" (6.9%). M characteristics were positively associated with education, sporting, self-confidence, and good adaptation to work situation. M scores correlated with reports of "tomboyism" as girls. There was essentially no difference in hormones or disease risk factors between M and F women. The number of (CAG) repeats in the microsatellite of the transactivating domain of the androgen receptor was 19 (2.3; M and SD). M characteristics were more pronounced in the presence of longer repeat stretches (n > 20). No associations were found with F scores. There were no significant associations to the number of tetranucleotide repeats (TTTA) in the fourth introne of the aromatase gene. It was concluded that a majority of women showed M type of personality traits, associated with normal hormones, somatic health, and a long microsatellite in the transactivating domain of the AR gene.
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| 7. |
- Baghaei, Fariba, 1964, et al.
(author)
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The CYP19 gene and associations with androgens and abdominal obesity in premenopausal women.
- 2003
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In: Obesity research. - : Wiley. - 1071-7323. ; 11:4, s. 578-85
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Journal article (peer-reviewed)abstract
- OBJECTIVE: Elevated androgens in women are associated with type 2 diabetes and are dependent on the conversion to estrogens by aromatase cytochrome P450. Polymorphisms of a tetranucleotide repeat [TTTA](n) in the fourth intron of the CYP19 gene are associated with endocrine-dependent diseases and were examined in relation to hormone levels and disease risk factors in premenopausal women. RESEARCH METHODS AND PROCEDURES: A population sample of women born in 1956 (n = 270) were genotyped for this polymorphism and the results set in relation to steroid hormones, including saliva cortisol, anthropometric variables, estimates of insulin, glucose and lipid metabolism, and blood pressure. RESULTS: Seven tetranucleotide repeat [TTTA](n) alleles were detected with allelic sizes of 168 to 195 bp, with a TCT deletion/insertion (168/171 bp) upstream of this microsatellite. Smoking was associated with elevated androgens (p = 0.005 to 0.019). Using the median (average stretch, 177.5 bp) as a dividing line, nonsmoking women with the shorter microsatellite had higher free testosterone (p = 0.018) and lower sex hormone binding globulin (p = 0.033). These differences were pronounced with the 168-bp allele. Such women were also characterized by a less-substantial decrease of morning cortisols ("unwinding"; p = 0.035) and central obesity (abdominal sagittal diameter, p = 0.049) and had waist/hip circumference ratios of borderline significance (p = 0.064). DISCUSSION: The results indicate that, in premenopausal women, a short microsatellite in the fourth intron of the CYP19 gene, caused by a TCT deletion upstream the [TTTA](n) tract, is associated with elevated androgens, perturbed regulation of the hypothalamic-pituitary-adrenal axis, and abdominal obesity.
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| 8. |
- Baghaei, Fariba, 1964, et al.
(author)
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The lean woman.
- 2002
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In: Obesity research. - : Wiley. - 1071-7323. ; 10:2, s. 115-21
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Journal article (peer-reviewed)abstract
- OBJECTIVE: In the current obesity epidemic, the ability to remain lean is beginning to be uncommon. Therefore, it was considered of interest to characterize such subjects. RESEARCH METHODS AND PROCEDURES: From a population of premenopausal women (n = 270), all 40 years of age, those with a similar body mass index (BMI) as women at the age of 21 years, born the same year (BMI = 21.1 kg/m(2)) were selected among nonsmokers and compared with the remaining nonsmoking women. RESULTS: Lean women showed, as expected, low waist-to-hip circumference ratio and abdominal sagittal diameter as well as absence of other disease risk factors. Compared with the remaining women, 17 beta-estradiol was high and androgens were low, whereas insulin-like growth factor I and thyroid hormones showed no differences. Dihydroepiandrosterone sulfate was lower, whereas cortisol, measured in saliva repeatedly over a day, and adrenocorticotropin hormone were not different. Results from questionnaires indicated higher education and socioeconomic status, frequent sports activities, and better psychosocial adaptation and psychological health. A tetranucleotide repeat polymorphism in the fourth [corrected] intron of the aromatase P450 gene was longer among the lean (187 base pairs) than the rest of the women. Women with opposite phylogenetic characteristic have a short microsatellite (168 base pairs) in this gene locus. DISCUSSION: Lean, nonsmoking women enjoy an excellent health in not only anthropometric and metabolic factors, but also in neuroendocrine, endocrine, and psychological variables. The endocrine measurements suggest a well-functioning aromatase, which in turn might have a genetic background, contributing to health. The aromatase gene might be important for regulation of body fat mass.
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| 9. |
- Brönnegård, Mikael, et al.
(author)
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Lack of evidence for estrogen and progesterone receptors in human adipose tissue.
- 1994
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In: The Journal of steroid biochemistry and molecular biology. - 0960-0760. ; 51:5-6, s. 275-81
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Journal article (peer-reviewed)abstract
- We have previously presented data indicating the absence of estrogen and progesterone receptors from human adipose tissue by the use of specific antibodies (Abbott) as well as specific ligands. In addition, specific estrogen and progesterone cRNA probes did not hybridize to any mRNA species in either abdominal or gluteal/femoral adipose tissue as demonstrated by solution hybridization and Northern blot. In order to demonstrate even extremely small quantities of gene products we have now used the Polymerase chain reaction-technique to study estrogen- and progesterone receptor gene expression. Sequences corresponding to each specific cDNA were demonstrated indicating small amounts of estrogen- and progesterone receptor mRNA not detected by RNA/RNA or RNA/TNA (total nucleic acids) hybridization assays. The estrogen receptor-regulated gene pS2, however, was not induced by estrogens in human adipose tissue in contrast to a significant increase in pS2 mRNA levels after estrogen exposure to the estrogen receptor(+) cell line MCF7. From these results we conclude that estrogen- and progesterone receptors are absent from human adipose tissue and that the extremely low level of transcription of the corresponding genes is not sufficient to allow translation of the message into functional proteins.
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| 10. |
- Dahlgren, Jovanna, 1964, et al.
(author)
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Prenatal cytokine exposure results in obesity and gender-specific programming.
- 2001
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In: American journal of physiology. Endocrinology and metabolism. - 0193-1849. ; 281:2
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Journal article (peer-reviewed)abstract
- Prenatal events appear to program hormonal homeostasis, contributing to the development of somatic disorders at an adult age. The aim of this study was to examine whether maternal exposure to cytokines or to dexamethasone (Dxm) would be followed by hormonal consequences in the offspring at adult age. Pregnant rats were injected on days 8, 10, and 12 of gestation with either human interleukin-6 (IL-6) or tumor necrosis factor-alpha (TNF-alpha) or with Dxm. Control dams were injected with vehicle. All exposed offspring developed increased body weight (P < 0.05--0.001), apparently due to an increase of 30--40% in adipose tissue weight (P < 0.05--0.01). Corticosterone response to stress was increased in the IL-6 group (P < 0.05-0.01). Dxm-treated male rats exhibited blunted Dexamethasone suppression test results. In male rats, insulin sensitivity was decreased after IL-6 exposure (P < 0.01), whereas basal insulin was elevated in the TNF-alpha group (P < 0.01). In female rats, plasma testosterone levels were higher in all exposed groups compared with controls (P < 0.01--0.001), with the exception of Dxm-exposed offspring. Males in the TNF-alpha group showed decreased locomotor activity (P < 0.05), and females in the IL-6 group showed increased locomotor activity (P < 0.05). These results indicate that prenatal exposure to cytokines or Dxm leads to increased fat depots in both genders. In females, cytokine exposure was followed by a state of hyperandrogenicity. The results suggest that prenatal exposure to cytokines or Dxm can induce gender-specific programming of neuroendocrine regulation with consequences in adult life.
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