Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0028754 (obesity)
 124,988 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The mechanisms of the production of estrogens and androgens in women and men are reviewed. Extraglandular estrogen formation from circulating androgens is the principal source of estrogen in men and postmenopausal women. The amount of estrogen formed is dependent upon precursor availability and metabolic factors, such as obesity and hepatic disease. Both androgens and estrogens in the circulation of humans are bound to sex hormone binding globulin which limits their availability to target cell receptors.
 ...
PMID:Sex hormone production and action. 22 77

Obese subjects have increased bone density relative to non-obese subjects yet this relationship is not fully understood. We examined whether alterations in sex hormones or binding proteins might explain the effect of obesity on osteoporosis in 83 premenopausal women from the San Antonio Heart Study, a population-based study of diabetes. We measured total testosterone, oestradiol, oestrone, sex hormone binding globulin (SHBG), and serum dehydroepiandrosterone sulphate (DHEA-SO4). Bone density was assessed by a Hologic dual photon absorptometer. Lumbar spine and femoral neck density were positively correlated with body mass index (BMI). In addition, femoral neck density was positively correlated with DHEA-SO4. BMI was negatively correlated with SHBG. After adjustment for sex hormones by multiple linear regression a positive association between bone density and obesity still exists suggesting that the association between obesity and bone density is at least partially independent of sex steroids in premenopausal women.
 ...
PMID:Excess androgenicity only partially explains the relationship between obesity and bone density in premenopausal women. 133 41

Serum sex hormone binding globulin (SHBG) concentration of children with obesity was measured and relationships between SHBG level and body mass index (BMI), waist hip ration (WHR), serum insulin, C-peptide, thyroid hormones (thyroxine--T4, triiodothyronine--T3/ sexual hormones (testosterone--T, oestradiol--E2) were investigated. Significant negative correlations were found between SHBG concentration and BMI, serum insulin, C-peptide concentration; significant positive concentrations were found between BMI and serum insulin, C-peptide concentration. Thyroid hormone and sexual hormones did not associate with SHBG levels. These results suggest that insulin hypersecretion has an important role in determining the reduction of SHBG production in obesity.
 ...
PMID:Sex hormone binding globulin (SHBG) in children with obesity. 138 19

Dietary intakes, anthropometric indices and plasma lipoprotein and alpha-tocopherol concentrations were measured in premenopausal vegetarian women of Indian descent (n = 22) and in white women of European descent consuming either mixed (n = 22) or vegetarian diets (n = 18). The Indian women were shorter in height than the white women and had a higher proportion of body fat. Energy intakes were lower in the Indian women, both in absolute terms and per kg body weight. The proportion of energy derived from saturated fatty acids was lower and that from polyunsaturated fatty acids was greater in both Indian and white vegetarians compared with the subjects on mixed diets. Intakes of dietary fibre and vitamins C and E were higher in the white vegetarians compared with the other groups. Plasma concentrations of total and LDL cholesterol and apolipoprotein B and the ratio of apolipoprotein B/apolipoprotein AI were lower and HDL and HDL2 cholesterol, alpha-tocopherol concentrations and the ratio of alpha-tocopherol/cholesterol were greater in the white vegetarian group than in the other groups. Total plasma cholesterol was associated with measures of truncal obesity, especially subscapular skinfold thickness and the percentage energy derived from saturated fatty acids. Plasma concentrations of apo(a) were higher and those of HDL and HDL2 cholesterol and sex hormone binding globulin (SHBG) were lower in the Indian vegetarian women compared with both groups of white women. No relationship could be found between apo(a), HDL and HDL2 cholesterol concentration and nutrient intake but HDL and HDL2 were negatively associated with the proportion of body fat and apo(a) weakly with subscapular skinfold thickness.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Lipoprotein risk factors in vegetarian women of Indian descent are unrelated to dietary intake. 141 95

Estrogen replacement therapy is widely used to treat menopausal symptoms and prevent osteoporosis. The mechanism of these and other estrogen effects is currently under investigation. We studied the plasma steroid hormone and sex hormone binding globulin levels in frozen plasma obtained from 977 women aged 50 to 79 years from 1972 to 1974. Almost all of the 301 women who reported current use of noncontraceptive estrogen were taking conjugated estrogen by mouth; none reported use of a progestin. Women taking estrogen were significantly younger, thinner, and more likely to smoke cigarettes than women not taking estrogen. Sex hormone binding globulin and all endogenous hormones except testosterone were negatively correlated with age; estradiol was positively and cortisol and sex hormone binding globulin were negatively associated with obesity. After adjusting for age and obesity, dehydroepiandrosterone sulfate, androstenedione, and free testosterone were significantly lower in women currently taking estrogen than in women not using estrogen. These differences were independent of cigarette smoking. As expected, estrogens (including free estradiol), sex hormone binding globulin, and cortisol levels were higher in treated than untreated women. The possibility that some of the benefits and risks of replacement estrogen are secondary to altered adrenal steroid metabolism and androgen levels needs further evaluation.
 ...
PMID:Exogenous estrogen and endogenous sex hormones. 154 58

The aim of the study was to examine the relationships of obesity, lipids and apolipoproteins with the risk for subsequent ischaemic heart disease in middle-aged women, using a case-control study nested within a cohort study. A total of 3634 women aged 26-88 were recruited in Guernsey between 1977 and 1985 and followed until June 1986 by abstraction of their general practitioners' records. Fifty-one cases of incident ischaemic heart disease (11 myocardial infarction, 40 angina) were identified. For each case up to 4 controls were selected, matched for age and date at recruitment. Odds ratios for the development of ischaemic heart disease in the middle and upper thirds of the distribution for each variable in the controls, relative to the lowest third (and two-sided P-values for linear trends), were: 3.0, 2.6 (0.015) for Quetelet's index; 3.3, 5.1 (0.003) for total cholesterol; 0.5, 0.6 (0.102) for apolipoprotein A-I; 1.8, 2.4 (0.015) for apolipoprotein B; 1.3, 2.1 (0.155) for apolipoprotein(a). The increased risks associated with increased Quetelet's index and total cholesterol were independent of each other and these variables were more strongly related to myocardial infarction than to angina. The relationships of risk with serum cotinine, fatty acids, dehydroepiandrosterone sulphate and sex hormone binding globulin were weak and did not approach statistical significance.
 ...
PMID:A prospective study of obesity, lipids, apolipoproteins and ischaemic heart disease in women. 163 46

Obesity may be characterized by abnormal sex steroid secretion and reduced sex hormone binding globulin (SHBG) which in turn is related to fat distribution and insulin secretion. Recent in-vitro and in-vivo evidence suggests that insulin is the common mechanism regulating the secretion of SHBG and insulin-like growth factor small binding protein (IGFBP-1). IGFBP-1 appears not only to be a carrier for insulin growth factors (IGFs) but also to play an active role in growth processes, independent of growth hormone secretion. We have examined the possible relationship between fasting insulin, SHBG, testosterone, IGF-1, IGFBP-1 and fat distribution in 25 extremely obese, menstruating women (mean weight 107 +/- 3 kg) with normal glucose tolerance. Fat distribution was assessed from measurements of the waist to hip ratio (W/H). The obese women showed an elevated fasting insulin (mean +/- SEM; 21 +/- 2 mumol/l), a normal IGF-1, but reduced IGFBP-1 (14.6 +/- 2 micrograms/l); in 15 women IGFBP-1 levels were undetectable by the present assay. In addition, SHBG levels were reduced in the obese women (24 +/- 2 nmol/l) but total testosterone values (1.9 +/- 0.1 nmol/l) were normal. The elevated fasting insulin levels were positively correlated with increasing upper segment obesity as expressed by a rising W/H ratio (P less than 0.01, r2 = 0.306) and inversely correlated with SHBG (P less than 0.01, r2 = 0.483). Similarly, reduced SHBG values showed an inverse correlation with increasing W/H ratio (P less than 0.001, r2 = 0.383). No correlation was found between IGFBP-1 and W/H ratio but a strong positive correlation was seen between IGFBP-1 and SHBG (P less than 0.001, r2 = 0.466). Furthermore, an equally significant inverse correlation was found between IGFBP-1 and insulin levels (P less than 0.001, r2 = 0.474).(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Decreased sex hormone binding globulin (SHBG) and insulin-like growth factor binding protein (IGFBP-1) in extreme obesity. 170 70

Hyperinsulinemia is a well-recognized entity of simple obesity. It is demonstrated that hyperinsulinemia is associated with upper body fat and fat cell hypertrophy. Androgen excess and lower levels of sex hormone binding globulin (SHBG) may produce fat cell hypertrophy and hyperinsulinemia as well. We measured serum insulin and C-peptide levels during an OGTT in two groups of obese premenopausal women to determine whether the hyperinsulinemia is due to hypersecretion or due to a diminished hepatic extraction of insulin. In this study, we found no correlation between the insulin and C-peptide levels or their ratio and the degree of obesity. However, a significant correlation was found between the waist-to-hip circumference ratio (WHR), used as an index of body fat distribution, and the areas of insulin (r = 0.55; P less than 0.001) and C-peptide (r = 0.51; P less than 0.001). SHBG and free androgen index (FAI) were also significantly related to these areas. The peripheral C-peptide/insulin molar ratio has been assumed to reflect changes in hepatic insulin extraction while the corrected C-peptide response reflects beta-cell function. WHR was negatively related to this ratio (r = -0.44; P less than 0.005) and SHBG showed a positive correlation (r = 0.34; P less than 0.05). Stepwise multiple regression analysis revealed that the 2-h insulin and C-peptide values and both curve areas can be explained up to 40-80% by sex hormones and anthropometric variables. Also the C-peptide/insulin molar ratio is dependent in a first step on WHR (r2 = 0.23; P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Decreased hepatic insulin extraction in upper body obesity: relationship to unbound androgens and sex hormone binding globulin. 187 8

The aim of this study was to assess the correlation between the distribution of adipose tissue, sexual hormones and hyperinsulinemia in male obesity. Fifty-two obese males, aged 40.0 +/- 10.9 years old and with a body mass index (BMI) of 35.0 +/- 6.1 (m +/- SD), not suffering from diabetes or any other endocrine disease, were included in the study. A group of 20 subjects aged 30.5 +/- 7.9 (p less than 0.005 vs obese subjects) and with a BMI of 23.0 +/- 2.0 were used as controls. Body fat distribution was assessed using the waist/hip ratio (w/h ratio): 0.985 +/- 0.052 in obese subjects and 0.913 +/- 0.061 in controls (p less than 0.005). In comparison to control subjects, significantly lower levels of total (T) (357 +/- 132 vs 498 +/- 142 ng/dl; p less than 0.005) and free testosterone (FT) (14.2 +/- 2.9 vs 17.1 +/- 2.6 pg/ml; p less than 0.05) were found in the obese group, as well sex hormone binding globulin (SHBG) (41.7 +/- 31.9 vs 66.2 +/- 18.6 nmol/l; p less than 0.001). None of the other steroids (androstenedione, dehydroepiandrosterone-sulphate, estrone, 17 beta-estradiol, dihydrotestosterone) or FSH and LH gonadotropins assayed differed between the two groups. Significantly higher levels of insulin and C-peptide, both fasting and after a oral glucose tolerance test, were also found in obese subjects.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:[Obesity and adipose tissue distribution in men: relation to sex steroids and insulin]. 194 14

While there is a general belief that hormone replacement therapy increases the risk of recurrence of breast cancer, there is in fact no hard data to prove this notion. Indirect evidence is provided, however, from observations on the effect of obesity on risk of breast cancer recurrence. This is because obesity is associated in postmenopausal women with increased circulating estrogen levels and obesity is also associated with lower sex hormone binding globulin levels so that the levels of non-SHBG bound estradiol are further increased.
 ...
PMID:The question of estrogen replacement therapy in patients with a prior diagnosis of breast cancer. 183 37


1 2 3 4 5 6 7 8 9 10 Next >>