| 1. |
- Alexanderson, Camilla, 1978, et al.
(författare)
-
A single early postnatal estradiol injection affects morphology and gene expression of the ovary and parametrial adipose tissue in adult female rats.
- 2010
-
Ingår i: The Journal of steroid biochemistry and molecular biology. - : Elsevier BV. - 1879-1220 .- 0960-0760. ; 122:1-3, s. 82-90
-
Tidskriftsartikel (refereegranskat)abstract
- Events during early life can affect reproductive and metabolic functions in adulthood. We evaluated the programming effects of a single early postnatal estradiol injection (within 3h after birth) in female rats. We assessed ovarian and parametrial adipose tissue morphology, evaluated gene expression related to follicular development and adipose tissue metabolism, and developed a non-invasive volumetric estimation of parametrial adipose tissue by magnetic resonance imaging. Estradiol reduced ovarian weight, increased antral follicle size and number of atretic antral follicles, and decreased theca interna thickness in atretic antral follicles. Adult estradiol-injected rats also had malformed vaginal openings and lacked corpora lutea, confirming anovulation. Estradiol markedly reduced parametrial adipose tissue mass. Adipocyte size was unchanged, suggesting reduced adipocyte number. Parametrial adipose tissue lipoprotein lipase activity was increased. In ovaries, estradiol increased mRNA expression of adiponectin, complement component 3, estrogen receptor alpha, and glucose transporter 3 and 4; in parametrial adipose tissue, expression of complement component 3 was increased, expression of estrogen receptor alpha was decreased, and expression of leptin, lipoprotein lipase, and hormone-sensitive lipase was unaffected. These findings suggest that early postnatal estradiol exposure of female rats result in long-lasting effects on the ovary and parametrial adipose tissue at adult age.
|
|
| 2. |
- Alexanderson, Camilla, 1978, et al.
(författare)
-
Early postnatal oestradiol exposure causes insulin resistance and signs of inflammation in circulation and skeletal muscle.
- 2009
-
Ingår i: The Journal of endocrinology. - 1479-6805. ; 201:1, s. 49-58
-
Tidskriftsartikel (refereegranskat)abstract
- Early postnatal events can predispose to metabolic and endocrine disease in adulthood. In this study, we evaluated the programming effects of a single early postnatal oestradiol injection on insulin sensitivity in adult female rats. We also assessed the expression of genes involved in inflammation and glucose metabolism in skeletal muscle and adipose tissue and analysed circulating inflammation markers as possible mediators of insulin resistance. Neonatal oestradiol exposure reduced insulin sensitivity and increased plasma levels of monocyte chemoattractant protein-1 (MCP-1) and soluble intercellular adhesion molecule-1. In skeletal muscle, oestradiol increased the expression of genes encoding complement component 3 (C3), Mcp-1, retinol binding protein-4 (Rbp4) and transforming growth factor beta1 (Tgfbeta1). C3 and MCP-1 are both related to insulin resistance, and C3, MCP-1 and TGFbeta1 are also involved in inflammation. Expression of genes encoding glucose transporter-4 (Glut 4), carnitine-palmitoyl transferase 1b (Cpt1b), peroxisome proliferator-activated receptor delta (Ppard) and uncoupling protein 3 (Ucp3), which are connected to glucose uptake, lipid oxidation, and energy uncoupling, was down regulated. Expression of several inflammatory genes in skeletal muscle correlated negatively with whole-body insulin sensitivity. In s.c. inguinal adipose tissue, expression of Tgfbeta1, Ppard and C3 was decreased, while expression of Rbp4 and Cpt1b was increased. Inguinal adipose tissue weight was increased but adipocyte size was unaltered, suggesting an increased number of adipocytes. We suggest that early neonatal oestrogen exposure may reduce insulin sensitivity by inducing chronic, low-grade systemic and skeletal muscle inflammation and disturbances of glucose and lipid metabolism in skeletal muscle in adulthood.
|
|
| 3. |
- Alexanderson, Camilla, 1978, et al.
(författare)
-
Postnatal testosterone exposure results in insulin resistance, enlarged mesenteric adipocytes, and an atherogenic lipid profile in adult female rats: comparisons with estradiol and dihydrotestosterone.
- 2007
-
Ingår i: Endocrinology. - : The Endocrine Society. - 0013-7227 .- 1945-7170. ; 148:11, s. 5369-76
-
Tidskriftsartikel (refereegranskat)abstract
- Postnatal events contribute to features of the metabolic syndrome in adulthood. In this study, postnatally administered testosterone reduced insulin sensitivity and increased the mesenteric fat depot, the size of mesenteric adipocytes, serum levels of total cholesterol, low-density lipoprotein cholesterol, and triglycerides, and the atherogenic index in adult female rats. To assess the involvement of estrogen and androgen receptors in these programming effects, we compared testosterone-exposed rats to rats exposed to estradiol or dihydrotestosterone (DHT). Estradiol-treated rats had lower insulin sensitivity than testosterone-treated rats and, like those rats, had enlarged mesenteric adipocytes and increased triglyceride levels. DHT also reduced insulin sensitivity but did not mimic the other metabolic effects of testosterone. All treated rats were probably anovulatory, but only those treated with testosterone had reduced testosterone levels. This study confirms our previous finding that postnatal administration of testosterone reduces insulin sensitivity in adult female rats and shows that this effect is accompanied by unfavorable changes in mesenteric fat tissue and in serum lipid levels. The findings in the estradiol and DHT groups suggest that estrogen receptors exert stronger metabolic programming effects than androgen receptors. Thus, insults such as sex hormone exposure in early life may have long-lasting effects, thereby creating a predisposition to disturbances in insulin sensitivity, adipose tissue, and lipid profile in adulthood.
|
|
| 4. |
- Gabrielsson, Britt, 1957, et al.
(författare)
-
Depot-specific expression of fibroblast growth factors in human adipose tissue.
- 2002
-
Ingår i: Obesity research. - : Wiley. - 1071-7323 .- 1550-8528. ; 10:7, s. 608-16
-
Tidskriftsartikel (refereegranskat)abstract
- We have investigated the expression of several fibroblast growth factors (FGFs) and FGF-receptors (FGFRs) in human adipose tissue and adipose-tissue cell fractions obtained from both subcutaneous (sc) and omental (om) depots.
|
|
| 5. |
- Gabrielsson, Britt, 1957, et al.
(författare)
-
Dietary herring improves plasma lipid profiles and reduces atherosclerosis in obese low-density lipoprotein receptor-deficient mice
- 2012
-
Ingår i: International Journal of Molecular Medicine. - : Spandidos Publications. - 1107-3756 .- 1791-244X. ; 29:3, s. 331-37
-
Tidskriftsartikel (refereegranskat)abstract
- Diet is a significant modifiable risk factor for cardiovascular disease and high fish intake has been associated with vascular health in population studies. However, intervention studies have been inconclusive. In this study, male low-density lipoprotein receptor-deficient mice were given 16-week high fat/high sucrose diets, supplemented with either minced herring fillets or minced beef. The diets were matched in total fat and cholesterol content; taurine content and fatty acid composition was analysed. Body weights were recorded throughout the study; plasma lipids were analysed at week 8 and 16. Body composition and adipocyte size were evaluated at study end. Atherosclerosis was evaluated at week 12 (ultrasound) and at termination (en face histology). Herring-fed mice had a higher proportion of long-chain n-3 polyunsaturated fatty acids in the hepatic triacylglycerides (TAG) and phospholipid fractions. The herring-fed mice had increased body weight (P=0.007), and reduced epididymal adipocyte size (P=0.009), despite similar food intake and body composition as the beef-fed mice. The herring-fed mice had lower plasma TAG and very-low-density lipoprotein (VLDL)-cholesterol concentrations throughout the study (TAG; P=0.0012 and 0.004, VLDL-cholesterol; P=0.006 and 0.041, week 8 and 16, respectively). At week 16, the herring-fed had higher plasma concentrations of HDL-cholesterol (P=0.004) and less atherosclerotic lesions in the aortic arch (P=0.007) compared with the beef-fed mice. In conclusion, dietary herring in comparison to beef markedly improved vascular health in this mouse model, suggesting that herring provides an added value beyond its content of macronutrients.
|
|
| 6. |
- Gabrielsson, Britt, 1957, et al.
(författare)
-
High expression of complement components in omental adipose tissue in obese men.
- 2003
-
Ingår i: Obesity research. - : Wiley. - 1071-7323 .- 1550-8528. ; 11:6, s. 699-708
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Accumulation of visceral fat is recognized as a predictor of obesity-related metabolic disturbances. Factors that are predominantly expressed in this depot could mediate the link between visceral obesity and associated diseases. RESEARCH METHODS AND PROCEDURES: Paired subcutaneous and omental adipose tissue biopsies were obtained from 10 obese men. Gene expression was analyzed by DNA microarrays in triplicate and by real-time polymerase chain reaction. Serum C3 and C4 were analyzed by radial immunodiffusion assays in 91 subjects representing a cross section of the general population. Body composition was measured by computerized tomography. RESULTS: Complement components C2, C3, C4, C7, and Factor B had higher expression in omental compared with subcutaneous adipose tissue ( approximately 2-, 4-, 17-, 10-, and 7-fold, respectively). In addition, adipsin, which belongs to the alternative pathway, and the classical pathway components C1QB, C1R, and C1S were expressed in both depots. Analysis of tissue distribution showed high expression of C2, C3, and C4 in omental adipose tissue, and only liver had higher expression of these genes. Serum C3 levels correlated with both visceral and subcutaneous adipose tissue in both men (r = 0.65 and p < 0.001 and r = 0.52 and p < 0.001, respectively) and women (r = 0.34 and p = 0.023 and r = 0.49 and p < 0.001, respectively), whereas C4 levels correlated with only visceral fat in men (r = 0.36, p = 0.015) and with both depots in women (visceral: r = 0.58, p < 0.001; and subcutaneous: r = 0.51, p < 0.001). DISCUSSION: Recent studies show that the metabolic syndrome is associated with chronically elevated levels of several immune markers, some of which may have metabolic effects. The high expression of complement genes in intra-abdominal adipose tissue might suggest that the complement system is involved in the development of visceral adiposity and/or contributes to the metabolic complications associated with increased visceral fat mass.
|
|
| 7. |
- Hall, Ulrika Andersson, et al.
(författare)
-
Longitudinal changes in adipokines and free leptin index during and after pregnancy in women with obesity.
- 2020
-
Ingår i: International journal of obesity. - : Springer Science and Business Media LLC. - 1476-5497 .- 0307-0565. ; 44, s. 675-683
-
Tidskriftsartikel (refereegranskat)abstract
- Detailed data on adipokines and body composition during and after pregnancy in women of different BMI categories are lacking. Furthermore, adipokine regulation during pregnancy and the factors contributing to gestational insulin resistance are not completely understood. The objective was to longitudinally determine adipokine levels, body composition, and insulin sensitivity during and after pregnancy in women of healthy weight (HW) and with obesity (OB), and identify factors associated with insulin resistance.Women (30 HW, 19 OB) underwent blood sampling and body composition examination, by air-displacement plethysmography, longitudinally during pregnancy (trimesters 1, 2, 3) and after pregnancy (6, 12, 18 months postpartum). Serum leptin, soluble leptin receptor (sOB-R), and adiponectin levels were measured and free leptin index (FLI) and homeostatic model assessment of insulin resistance (HOMA-IR) determined.Fat mass and leptin increased during pregnancy in the HW (p<0.01) but not in the OB group. sOB-R increased during pregnancy in both groups (p<0.001). Thus, FLI was unchanged in HW throughout pregnancy but reduced in OB (p=0.001), although consistently higher in OB. Adiponectin decreased in both groups during pregnancy (p<0.001 for HW, p=0.01 for OB). After pregnancy, adiponectin increased in both groups, but more markedly in OB where it reached trimester 1 levels. Multivariable regression identified FLI as the variable most strongly associated with HOMA-IR in all trimesters, but not after pregnancy.Leptin, sOB-R, adiponectin, and FLI undergo marked changes during and after pregnancy with differences in women of different BMI. We suggest that leptin activity is regulated by its soluble receptor and that this is an important factor for optimizing fat mass and insulin sensitivity during pregnancy.
|
|
| 8. |
- Lager, Susanne, 1978, et al.
(författare)
-
Perinatal lack of maternal IL-6 promotes increased adiposity during adulthood in mice.
- 2011
-
Ingår i: Endocrinology. - : The Endocrine Society. - 1945-7170 .- 0013-7227. ; 152:4, s. 1336-46
-
Tidskriftsartikel (refereegranskat)abstract
- The perinatal environment appears important in establishing metabolic phenotypes in adulthood. Mice deficient in IL-6 (IL-6(-/-)) tend to develop mature-onset obesity, but it is unknown whether perinatal exposure to IL-6 produced by the dam influences the metabolism of adult offspring. To address this issue, we monitored IL-6(-/-) offspring of IL-6(-/-) or IL-6(+/-) dams, as well as wild-type (WT) mice. At adult age, IL-6(-/-) mice weighed significantly more and had more body fat than WT mice, regardless of maternal genotype, and had lower insulin sensitivity. This phenotype was more pronounced in IL-6(-/-) offspring of IL-6(-/-) dams, because they gained weight significantly faster than IL-6(-/-) offspring of IL-6(+/-) dams and had more body fat and higher serum leptin levels at an earlier age. The leptin content was 2-fold higher in milk from IL-6(-/-) than WT dams. However, cross-fostering IL-6(-/-) mice with WT dams did not alter body weight, body composition, or adipocyte size at adult age compared with IL-6(-/-) mice fostered by IL-6(-/-) dams. Conversely, WT mice fostered by IL-6(-/-) dams weighed significantly more than those fostered by WT dams and had more body fat, larger adipocytes, and altered hypothalamic gene expression. We conclude that body fat of adult mice can be increased by perinatal exposure to factors affected by lack of maternal IL-6.
|
|
| 9. |
- Lindqvist, Helen, 1977, et al.
(författare)
-
Influence of herring (Clupea harengus) and herring fractions on metabolic status in rats fed a high energy diet.
- 2009
-
Ingår i: Acta physiologica (Oxford, England). - : Wiley. - 1748-1716 .- 1748-1708. ; 196:3, s. 303-14
-
Tidskriftsartikel (refereegranskat)abstract
- AIM: Few dietary studies have looked beyond fish oil to explain the beneficial metabolic effects of a fish-containing diet. Our aim was to study whether addition of herring, or sub-fractions of herring, could counteract negative metabolic effects known to be induced by a high-fat, high-sugar diet. METHODS: Rats were given six different diets: standard pellets; high energy diet with chicken mince (HiE control); high energy diet with herring mince (HiE herring); and high energy diet with chicken mince and either herring oil (HiE herring oil), herring press juice, PJ (HiE PJ) or herring low molecular weight PJ (HiE LMW-PJ). Factors associated with the metabolic syndrome were measured. RESULTS: There were no differences in energy intake or body weight between the groups, but animals fed high energy diets had a higher body fat content compared with the pellet group, although not statistically significant in all groups. Mesenteric adipocyte size was smaller in the HiE herring oil group compared with the HiE control. Glucose clamp studies showed that, compared with the pellet group, the HiE control and HiE herring diets, but not the HiE herring oil diet, induced insulin resistance. Addition of herring or herring oil to the high energy diet decreased total cholesterol levels, triacylglycerols and the atherogenic index compared with the HiE control group. CONCLUSIONS: The results suggest that addition of herring or herring oil counteracts negative effects on blood lipids induced by a high energy diet. The lipid component of herring thus seems to be responsible for these beneficial effects.
|
|
| 10. |
- Malmberg, Per, 1974, et al.
(författare)
-
A new approach to measuring vitamin D in human adipose tissue using time-of-flight secondary ion mass spectrometry: A pilot study
- 2014
-
Ingår i: Journal of Photochemistry and Photobiology. B: Biology. - : Elsevier BV. - 1011-1344. ; 138, s. 295-301
-
Tidskriftsartikel (refereegranskat)abstract
- Circulating concentrations of vitamin D, 25(OH)D, and 1,25(OH)2D are lower in obese than lean individuals, but little is known about the adipose tissue content of these molecules. The aim of this study was to explore the possibility to use time-of-flight secondary ion mass spectrometry (TOF-SIMS) to measure vitamin D and its metabolites in fat tissue in obese and lean subjects. Abdominal subcutaneous adipose tissue (SAT) biopsies were obtained from three lean and three obese women, and paired biopsies SAT and visceral adipose tissue (VAT) were obtained from three obese subjects during gastric bypass surgery. TOF-SIMS was used to measure vitamin D3, 25(OH)D3, and 1,25(OH)2D3 in adipose tissue. We found that vitamin D3, 25(OH)D3, and 1,25(OH)2D3 in adipose tissue can be measured with TOF-SIMS. In adipose tissue, vitamin D3 and its metabolites were located in adipocyte lipid droplets. The content of vitamin D3 (P = 0.006) and 25(OH)D3 (P = 0.018) were lower in SAT in obese compared with lean women. TOF-SIMS has the potential to semi-quantitatively measure vitamin D metabolites in adipose tissue, and offers a possibility to compare vitamin D levels in different depots and groups of individuals. It also gives the opportunity to explore the localization of vitamin D metabolites at a cellular level.
|
|
| 11. |
- Mannerås Holm, Louise, 1980, et al.
(författare)
-
Adipose tissue has aberrant morphology and function in PCOS: enlarged adipocytes and low serum adiponectin, but not circulating sex steroids, are strongly associated with insulin resistance.
- 2011
-
Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 96:2
-
Tidskriftsartikel (refereegranskat)abstract
- Context: Comprehensive characterization of the adipose tissue in women with polycystic ovary syndrome (PCOS), over a wide range of body mass indices (BMIs), is lacking. Mechanisms behind insulin resistance in PCOS are unclear. Objective: To characterize the adipose tissue of women with PCOS and controls matched pair-wise for age and BMI, and to identify factors, among adipose tissue characteristics and serum sex steroids, that are associated with insulin sensitivity in PCOS. Design/Outcome Measures: Seventy-four PCOS women and 31 controls were included. BMI was 18-47 (PCOS) and 19-41 kg/m2 (controls). Anthropometric variables, volumes of subcutaneous/visceral adipose tissue (magnetic resonance imaging; MRI), and insulin sensitivity (clamp) were investigated. Adipose tissue biopsies were obtained to determine adipocyte size, lipoprotein lipase (LPL) activity, and macrophage density. Circulating testosterone, free testosterone, free 17β-estradiol, SHBG, glycerol, adiponectin, and serum amyloid A were measured/calculated. Results: Comparison of 31 pairs revealed lower insulin sensitivity, hyperandrogenemia, and higher free 17β-estradiol in PCOS. Abdominal adipose tissue volumes/distribution did not differ in the groups, but PCOS women had higher waist-to-hip ratio, enlarged adipocytes, reduced adiponectin, and lower LPL activity. In regression analysis, adipocyte size, adiponectin, and waist circumference were the factors most strongly associated with insulin sensitivity in PCOS (R2=0.681, P < 0.001). Conclusions: In PCOS, adipose tissue has aberrant morphology/function. Increased waist-to-hip ratio indicates abdominal/visceral fat accumulation, but this is not supported by MRI. Enlarged adipocytes and reduced serum adiponectin, together with a large waistline, rather than androgen excess, may be central factors in the pathogenesis/maintenance of insulin resistance in PCOS.
|
|
| 12. |
- Mannerås, Louise, 1980, et al.
(författare)
-
A new rat model exhibiting both ovarian and metabolic characteristics of polycystic ovary syndrome.
- 2007
-
Ingår i: Endocrinology. - : The Endocrine Society. - 0013-7227 .- 1945-7170. ; 148:8, s. 3781-91
-
Tidskriftsartikel (refereegranskat)abstract
- Polycystic ovary syndrome (PCOS) is a complex endocrine and metabolic disorder associated with ovulatory dysfunction, hyperandrogenism, abdominal obesity, and insulin resistance. However, its etiology is unclear, and its management is often unsatisfactory or requires a diversified approach. Here, we describe a new rat PCOS model, the first to exhibit both ovarian and metabolic characteristics of the syndrome. Female rats received the nonaromatizable androgen dihydrotestosterone (DHT) or the aromatase inhibitor letrozole by continuous administration, beginning before puberty, to activate androgen receptors. Adult DHT rats had irregular cycles, polycystic ovaries characterized by cysts formed from atretic follicles, and a diminished granulosa layer. They also displayed metabolic features, including increased body weight, increased body fat, and enlarged mesenteric adipocytes, as well as elevated leptin levels and insulin resistance. All letrozole rats were anovulatory and developed polycystic ovaries with structural changes strikingly similar to those in human PCOS. Our findings suggest that the formation of a "hyperplastic" theca interna reflects the inclusion of luteinized granulosa cells in the cyst wall rather than true hyperplasia. We conclude that the letrozole model is suitable for studies of the ovarian features of human PCOS, while the DHT model is suitable for studies of both ovarian and metabolic features of the syndrome.
|
|
| 13. |
- Mannerås, Louise, 1980, et al.
(författare)
-
Low-frequency electro-acupuncture and physical exercise improve metabolic disturbances and modulate gene expression in adipose tissue in rats with dihydrotestosterone-induced polycystic ovary syndrome.
- 2008
-
Ingår i: Endocrinology. - : The Endocrine Society. - 0013-7227 .- 1945-7170. ; 149:7, s. 3559-68
-
Tidskriftsartikel (refereegranskat)abstract
- Polycystic ovary syndrome (PCOS) is a complex endocrine and metabolic disorder associated with ovulatory dysfunction, hyperandrogenism, abdominal obesity, and insulin resistance. Pharmacotherapy is often unsatisfactory. This study evaluates the effects of low-frequency electro-acupuncture (EA) and physical exercise on metabolic disturbances and adipose tissue mRNA expression of selected genes in a rat PCOS model characterized by insulin resistance and adiposity. Dihydrotestosterone (inducing PCOS) or vehicle (control) was administrated continuously, beginning before puberty. At age 10 wk, PCOS rats were randomly divided into three groups; PCOS, PCOS EA, and PCOS exercise. PCOS EA rats received 2-Hz EA (evoking muscle twitches) three times/wk during 4-5 wk. PCOS exercise rats had free access to a running wheel for 4-5 wk. EA and exercise improved insulin sensitivity, measured by clamp, in PCOS rats. Exercise also reduced adiposity, visceral adipocyte size, and plasma leptin. EA increased plasma IGF-I. Real-time RT-PCR revealed increased expression of leptin and IL-6 and decreased expression of uncoupling protein 2 in visceral adipose tissue of PCOS rats compared with controls. EA restored the expression of leptin and uncoupling protein 2, whereas exercise normalized adipose tissue leptin and IL-6 expression in PCOS rats. Thus, EA and exercise ameliorate insulin resistance in rats with PCOS. This effect may involve regulation of adipose tissue metabolism and production because EA and exercise each partly restore divergent adipose tissue gene expression associated with insulin resistance, obesity, and inflammation. In contrast to exercise, EA improves insulin sensitivity and modulates adipose tissue gene expression without influencing adipose tissue mass and cellularity.
|
|
| 14. |
- Palming, Jenny, 1975, et al.
(författare)
-
The expression of NAD(P)H:quinone oxidoreductase 1 is high in human adipose tissue, reduced by weight loss, and correlates with adiposity, insulin sensitivity, and markers of liver dysfunction.
- 2007
-
Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 92:6, s. 2346-52
-
Tidskriftsartikel (refereegranskat)abstract
- CONTEXT: We have previously identified nicotinamide adenine dinucleotide phosphate:quinone oxidoreductase 1 (NQO1), an enzyme involved in the protection against oxidative stress, as a gene predominantly expressed in human adipocytes. Studies in mice deficient in NQO1 activity suggest that NQO1 may also play an important role in metabolism. OBJECTIVE: The aim of this study was to explore the expression and regulation of NQO1 in human adipose tissue (AT) and isolated adipocytes. PATIENTS AND RESULTS: The high expression of NQO1 in adipocytes was verified in human adipocytes and AT by real-time PCR. DNA microarray analysis showed that NQO1 was expressed at higher levels in large compared with small adipocytes, isolated from the same fat biopsy. Furthermore, NQO1 mRNA levels were positively correlated with adipocyte size (n = 7; P < 0.002). During an 18-wk diet regime (n = 24; mean weight loss 27 kg), the NQO1 expression in human sc AT was down-regulated (P < 0.0001), and mRNA levels correlated with body mass index (P = 0.0005), sc, and total abdominal AT areas, as determined by computerized tomography (P < 0.0001, both) and metabolic parameters. NQO1 mRNA levels were also positively correlated with aspartate aminotransferase (P = 0.0028) and alanine aminotransferase (P = 0.0219), markers known to be associated with severity of hepatic steatosis. CONCLUSIONS: NQO1 is highly expressed in human AT, particularly in large adipocytes. AT NQO1 expression is reduced during diet-induced weight loss, and the expression levels positively correlate with adiposity, glucose tolerance, and markers of liver dysfunction. Together, these findings indicate a role for NQO1 in the metabolic complications of human obesity.
|
|
| 15. |
- Svensson, Henrik, 1982, et al.
(författare)
-
Adipose tissue and body composition in women six years after gestational diabetes: factors associated with development of type 2 diabetes.
- 2018
-
Ingår i: Adipocyte. - : Informa UK Limited. - 2162-397X .- 2162-3945. ; 7:4, s. 229-237
-
Tidskriftsartikel (refereegranskat)abstract
- Factors differentiating women at highest risk of progression to type 2 diabetes mellitus (T2DM) after gestational diabetes mellitus (GDM) are incompletely known. Our aim was to characterize adipose tissue and body composition in relation to glucose metabolism in women with a history of GDM and to identify factors associated with development of T2DM. We examined glucose tolerance (OGTT), insulin sensitivity (HOMA-IR), body composition (anthropometry, air displacement plethysmography), and blood chemistry in 39 women 6years after GDM. An adipose tissue biopsy was obtained to assess the size, number, and lipolytic activity of adipocytes, and adipokine release and density of immune cells and blood vessels in adipose tissue. Normal glucose tolerance (NGT) was identified in 31 women and impaired glucose metabolism (IGM) in 8. Women with IGM had higher BMI/fat mass, and related expected adipose tissue features, than women with NGT. Ethnicity was similar in the groups, but numerically there was a higher proportion of European women in the NGT group and a higher proportion of non-European women in the IGM group. BMI was the best discriminator of NGT versus IGM (multivariable logistic regression: OR=1.34, P<0.01). Waist-to-height ratio and adipocyte volume were most strongly associated with HOMA-IR (multivariable linear regression: R2=0.656, P<0.001). After adjustment for BMI/ethnicity, women with IGM had increased serum adipocyte fatty acid-binding protein, weight gain after index pregnancy, and a lower proportion of fat-free mass. These factors, together with high BMI, abdominal fat distribution, and enlarged adipocytes, may increase the risk of progression to T2DM after GDM.
|
|
| 16. |
- Svensson, Henrik, 1982, et al.
(författare)
-
Body fat mass and the proportion of very large adipocytes in pregnant women are associated with gestational insulin resistance.
- 2016
-
Ingår i: International journal of obesity (2005). - : Springer Science and Business Media LLC. - 1476-5497 .- 0307-0565. ; 40, s. 646-653
-
Tidskriftsartikel (refereegranskat)abstract
- Pregnancy is accompanied by fat gain and insulin resistance. Changes in adipose tissue morphology and function during pregnancy and factors contributing to gestational insulin resistance are incompletely known. We sought to characterize adipose tissue in trimesters 1 and 3 (T1/T3) in normal weight (NW) and obese pregnant women, and identify adipose tissue-related factors associated with gestational insulin resistance.
|
|
| 17. |
- Svensson, Henrik, 1982, et al.
(författare)
-
Free lipid and computerized determination of adipocyte size.
- 2018
-
Ingår i: Adipocyte. - : Informa UK Limited. - 2162-397X .- 2162-3945. ; 7:3, s. 180-182
-
Tidskriftsartikel (refereegranskat)abstract
- The size distribution of adipocytes in a suspension, after collagenase digestion of adipose tissue, can be determined by computerized image analysis. Free lipid, forming droplets, in such suspensions implicates a bias since droplets present in the images may be identified as adipocytes. This problem is not always adjusted for and some reports state that distinguishing droplets and cells is a considerable problem. In addition, if the droplets originate mainly from rupture of large adipocytes, as often described, this will also bias size analysis. We here confirm that our ordinary manual means of distinguishing droplets and adipocytes in the images ensure correct and rapid identification before exclusion of the droplets. Further, in our suspensions, prepared with focus on gentle handling of tissue and cells, we find no association between the amount of free lipid and mean adipocyte size or proportion of large adipocytes.
|
|
| 18. |
- Björnheden, Tom, 1945, et al.
(författare)
-
Computerized determination of adipocyte size.
- 2004
-
Ingår i: Obesity research. - 1071-7323. ; 12:1, s. 95-105
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Fat cell size is a fundamental parameter in the study of adipose tissue metabolism, because it markedly influences the cellular rates of metabolism. Previous techniques for the sizing of adipocytes are often complicated or time-consuming. The aim of this study was to develop a new, computerized method for rapid and accurate determination of adipocyte size in a cell suspension obtained by incubating human or rat adipose tissue biopsies with collagenase. RESEARCH METHODS AND PROCEDURES: The cell suspension was placed between a siliconized glass slide and a cover slip. Using the reference method [designated as (R)], the cell diameters were determined manually using a microscope with a calibrated ocular. The new method presented here [designated as (C)] was based on computerized image analysis. RESULTS: After two well-defined corrective adjustments, measurements with (R) and (C) agreed very well. The small remaining differences seemed, in fact, to depend on inconsistencies in (R). DISCUSSION: We propose that (C) constitutes a valuable tool to study fat cell size, because this method is fast and allows the assessment of a sufficient number of cells to get reliable data on size distribution. Furthermore, images of cell preparations may be stored for future reference.
|
|
| 19. |
- Brogren, Helén, 1977, et al.
(författare)
-
Heterogeneous glycosylation patterns of human PAI-1 may reveal its cellular origin.
- 2008
-
Ingår i: Thrombosis research. - : Elsevier BV. - 0049-3848. ; 122:2, s. 271-81
-
Tidskriftsartikel (refereegranskat)abstract
- The main inhibitor of intravascular fibrinolysis is plasminogen activator inhibitor 1 (PAI-1) which binds to and irreversibly inhibits tissue plasminogen activator (tPA). PAI-1 is present in blood, both in platelets and in plasma, and PAI-1 levels are associated with risk of atherothrombosis. Several tissues express PAI-1 but the source of plasma PAI-1 is not known. We recently found that platelets can de novo synthesize PAI-1 and the amount synthesized in vitro in 24 hours is 35-fold higher than required to maintain normal plasma levels. Recombinant human PAI-1 expressed in different cell types or secreted naturally by human cell lines, exhibit heterogeneous glycosylation patterns. The aim of this study was to investigate the hypothesis that platelets might be the source of plasma PAI-1 and that the cellular source of PAI-1 can be determined by its tissue-specific glycosylation pattern. PAI-1 was isolated from platelets, macrophages, endothelial cells, adipose tissue, as well as plasma from lean and obese subjects. The glycosylation was analyzed by nanoLC-MS/MS. PAI-1 isolated from cell lysates and conditioned media from macrophages, endothelial cells, and adipose tissue expressed heterogeneous glycosylation patterns. By contrast, no glycans were detected on PAI-1 isolated from plasma or platelets from healthy lean individuals. Hence, our data suggest that platelets may be the main source of plasma PAI-1 in lean individuals. Interestingly, plasma PAI-1 from obese subjects had a glycan composition similar to that of adipose tissue suggesting that obese subjects with elevated PAI-1 levels may have a major contribution from other tissues.
|
|
| 20. |
- Gabrielsson, Britt, 1957, et al.
(författare)
-
Evaluation of reference genes for studies of gene expression in human adipose tissue.
- 2005
-
Ingår i: Obesity research. - 1071-7323 .- 1550-8528. ; 13:4, s. 649-52
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: The aim of this study was to evaluate reference genes for expression studies of human adipose tissue. RESEARCH METHODS AND PROCEDURES: Using 52 human adipose tissue expression profiles (HU95), 10 putative reference genes with the lowest variation in expression levels were selected for further studies. Expression stability of these 10 novel and 5 previously established reference genes was evaluated by real-time reverse transcriptase-polymerase chain reaction analysis. For this purpose, 44 adipose tissue biopsies from 27 subjects were chosen to include a wide range of parameters such as sex, age, BMI, depot origin, biopsy procedure, and effects of nutrition. RESULTS: LRP10 was identified as the gene with the least variation in expression levels. The frequently used reference genes RPLP0, 18S rRNA, PPIA, ACTB, and GAPD were ranked as 4, 6, 7, 8, and 10, respectively. DISCUSSION: Our results suggest that LRP10 is a better choice as reference for expression studies of human adipose tissue compared with the most frequently used reference genes.
|
|
| 21. |
- Gabrielsson, Britt, 1957, et al.
(författare)
-
Molecular characterization of a local sulfonylurea system in human adipose tissue.
- 2004
-
Ingår i: Molecular and cellular biochemistry. - 0300-8177 .- 1573-4919. ; 258:1-2, s. 65-71
-
Tidskriftsartikel (refereegranskat)abstract
- ATP-sensitive potassium (KATP) channels are present in many cell types and link cellular metabolism to the membrane potential. These channels are heterooctamers composed of two subunits. The sulfonylurea receptor (SUR) subunits are targets for drugs that are inhibitors or openers of the KATP channels, while the inwardly rectifying K+ (Kir) subunits form the ion channel. Two different SUR genes (SUR1 and SUR2) and two different Kir6.x genes (Kir6.1 and Kir6.2) have been identified. In addition, isoforms of SUR2, SUR2A and SUR2B, have been described. We have previously performed expression profiling on pooled human adipose tissue and found high expression of SUR2. Others have reported expression of SUR1 in human adipocytes. The aim of this study was to characterize the expression of the sulfonylurea receptor complex components in human adipose tissue. RT-PCR analysis, verified by restriction enzyme digestions and DNA sequencing, showed that SUR2B, Kir6.1 and alpha-endosulfine, but not SUR1, SUR2A or Kir6.2, are expressed in human adipose tissue. Real-time RT-PCR showed that SUR2B was expressed at higher levels in subcutaneous compared with omental adipose tissue in paired biopsies obtained from seven obese men (p < 0.05). Analysis of tissue distribution showed that SUR2B expression in adipose tissue was lower than that in muscle, similar to that in heart and liver, while the expression in pancreas was lower. The effect of caloric restriction was tested in obese men (n = 10) treated with very low calorie diet for 16 weeks, followed by a gradual reintroduction of ordinary food for 2 weeks. Biopsies were taken at week 0, 8 and 18. There was no consistent effect of weight reduction on SUR2B or Kir6.1 expression. We conclude that the necessary components for a local sulfonylurea system are expressed in human adipose tissue and that the sulfonylurea receptor complex in this tissue is composed of SUR2B and Kir6.1. The expression of SUR2B was higher in subcutaneous compared with omental adipose tissue and was not affected by weight loss.
|
|
| 22. |
- Jernås, Margareta, 1961, et al.
(författare)
-
Separation of human adipocytes by size: hypertrophic fat cells display distinct gene expression
- 2006
-
Ingår i: The FASEB Journal. - : Wiley. - 1530-6860 .- 0892-6638. ; 20
-
Tidskriftsartikel (refereegranskat)abstract
- Enlarged adipocytes are associated with insulin resistance and are an independent predictor of type 2 diabetes. To understand the molecular link between these diseases and adipocyte hypertrophy, we developed a technique to separate human adipocytes from an adipose tissue sample into populations of small cells (mean 57.6+-3.54 um) and large cells (mean 100.1+-3.94 um). Microarray analysis of the cell populations separated from adipose tissue from three subjects identified 14 genes, of which five immune-related, with more than fourfold higher expression in large cells than small cells. Two of these genes were serum amyloid A (SAA) and transmembrane 4 L six family member 1 (TM4SF1). Real-time RT-PCR analysis of SAA and TM4SF1 expression in adipocytes from seven subjects revealed 19-fold and 22-fold higher expression in the large cells, respectively, and a correlation between adipocyte size and both SAA and TM4SF1 expression. The results were verified using immunohistochemistry. In comparison with 17 other human tissues and cell types by microarray, large adipocytes displayed by far the highest SAA and TM4SF1 expression. Thus, we have identified genes with markedly higher expression in large, compared with small, human adipocytes. These genes may link hypertrophic obesity to insulin resistance/type 2 diabetes.
|
|
| 23. |
- Johannsson, Gudmundur, 1960, et al.
(författare)
-
Growth hormone treatment of abdominally obese men reduces abdominal fat mass, improves glucose and lipoprotein metabolism, and reduces diastolic blood pressure.
- 1997
-
Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 0021-972X. ; 82:3, s. 727-34
-
Tidskriftsartikel (refereegranskat)abstract
- The most central findings in both GH deficiency in adults and the metabolic syndrome are abdominal/visceral obesity and insulin resistance. Abdominal obesity is associated with blunted GH secretion and low serum insulin-like growth factor-I concentrations. GH treatment in GH-deficient adults has demonstrated favorable effects on most of the features of GH deficiency in adults, but it is not known whether GH can improve some of the metabolic aberrations observed in abdominal/visceral obesity. Thirty men, 48-66 yr old, with abdominal/visceral obesity were treated with recombinant human GH (rhGH) in a 9-month randomized, double-blind, placebo-controlled trial. The daily dose of rhGH was 9.5 micrograms/kg. Body fat was assessed from total body potassium, and abdominal sc and visceral adipose tissue was measured using computed tomography. The glucose disposal rate (GDR) was measured during an euglycemic, hyperinsulinemic glucose clamp. In response to the rhGH treatment, total body fat and abdominal sc and visceral adipose tissue decreased by 9.2 +/- 2.4%, 6.1 +/- 3.2%, and 18.1 +/- 7.6%, respectively. After an initial decrease in the GDR at 6 weeks, the GDR increased in the rhGH-treated group as compared with the placebo-treated one (P < 0.05). The mean serum concentrations of total cholesterol (P < 0.01) and triglyceride (P < 0.05) decreased, whereas blood glucose and serum insulin concentrations were unaffected by the rhGH treatment. Furthermore, diastolic blood pressure decreased and systolic blood pressure was unchanged in response to rhGH treatment. This trial has demonstrated that GH can favorably affect some of the multiple perturbations associated with abdominal/visceral obesity. This includes a reduction in abdominal/visceral obesity, an improved insulin sensitivity, and favorable effects on lipoprotein metabolism and diastolic blood pressure.
|
|
| 24. |
- Johansson, Julia, 1982, et al.
(författare)
-
Electrical vs Manual Acupuncture Stimulation in a Rat Model of Polycystic Ovary Syndrome: Different Effects on Muscle and Fat Tissue Insulin Signaling
- 2013
-
Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 8:1
-
Tidskriftsartikel (refereegranskat)abstract
- In rats with dihydrotestosterone (DHT)-induced polycystic ovary syndrome (PCOS), repeated low-frequency electrical stimulation of acupuncture needles restores whole-body insulin sensitivity measured by euglycemic hyperinsulinemic clamp. We hypothesized that electrical stimulation causing muscle contractions and manual stimulation causing needle sensation have different effects on insulin sensitivity and related signaling pathways in skeletal muscle and adipose tissue, with electrical stimulation being more effective in DHT-induced PCOS rats. From age 70 days, rats received manual or low-frequency electrical stimulation of needles in abdominal and hind limb muscle five times/wk for 4–5 wks; controls were handled but untreated rats. Low-frequency electrical stimulation modified gene expression (decreased Tbc1d1 in soleus, increased Nr4a3 in mesenteric fat) and protein expression (increased pAS160/AS160, Nr4a3 and decreased GLUT4) by western blot and increased GLUT4 expression by immunohistochemistry in soleus muscle; glucose clearance during oral glucose tolerance tests was unaffected. Manual stimulation led to faster glucose clearance and modified mainly gene expression in mesenteric adipose tissue (increased Nr4a3, Mapk3/Erk, Adcy3, Gsk3b), but not protein expression to the same extent; however, Nr4a3 was reduced in soleus muscle. The novel finding is that electrical and manual muscle stimulation affect glucose homeostasis in DHT-induced PCOS rats through different mechanisms. Repeated electrical stimulation regulated key functional molecular pathways important for insulin sensitivity in soleus muscle and mesenteric adipose tissue to a larger extent than manual stimulation. Manual stimulation improved whole-body glucose tolerance, an effect not observed after electrical stimulation, but did not affect molecular signaling pathways to the same extent as electrical stimulation. Although more functional signaling pathways related to insulin sensitivity were affected by electrical stimulation, our findings suggest that manual stimulation of acupuncture needles has a greater effect on glucose tolerance. The underlying mechanism of the differential effects of the intermittent manual and the continuous electrical stimulation remains to be elucidated.
|
|
| 25. |
- Johansson, Julia, 1982, et al.
(författare)
-
Intense electroacupuncture normalizes insulin sensitivity, increases muscle GLUT4 content, and improves lipid profile in a rat model of polycystic ovary syndrome.
- 2010
-
Ingår i: American journal of physiology. Endocrinology and metabolism. - : American Physiological Society. - 1522-1555 .- 0193-1849. ; 299:4
-
Tidskriftsartikel (refereegranskat)abstract
- Polycystic ovary syndrome (PCOS) is associated with hyperandrogenism and insulin resistance, possibly reflecting defects in skeletal muscle and adipocyte insulin signaling. Low-frequency (2 Hz) electroacupuncture (EA) increases insulin sensitivity in female rats with dihydrotestosterone (DHT)-induced PCOS, but the mechanism is unclear. We hypothesized that low-frequency EA regulates mediators involved in skeletal muscle glucose uptake and metabolism and alters the lipid profile in rats with DHT-induced PCOS. To test this hypothesis, we implanted in prepubescent female rats 90-day continuous-release pellets containing DHT (PCOS). At 70 days of age, the rats were randomly subdivided into two groups: one received low-frequency EA (evoking muscle twitches) for 20-25 min five times/wk for 4-5 wk; the other did not. Controls were implanted with pellets containing vehicle only. All three groups were otherwise handled similarly. Lipid profile was measured in fasting blood samples. Insulin sensitivity was determined by euglycemic hyperinsulinemic clamp, soleus muscle protein expression of glucose transporter 4 (GLUT4), and phosphorylated and nonphosphorylated Akt, and Akt substrate of 160 kDa was determined by Western blot analysis and GLUT4 location by immunofluorescence staining. PCOS EA rats had normalized insulin sensitivity, lower levels of total high-density lipoprotein and low-density lipoprotein cholesterol, and increased expression of GLUT4 in different compartments of skeletal muscle compared with PCOS rats. Total weight and body composition did not differ in the groups. Thus, in rats with DHT-induced PCOS, low-frequency EA has systemic and local effects involving intracellular signaling pathways in muscle that may, at least in part, account for the marked improved insulin sensitivity.
|
|
| 26. |
- Korotkova, Marina, 1954, et al.
(författare)
-
Leptin levels in rat offspring are modified by the ratio of linoleic to alpha-linolenic acid in the maternal diet
- 2002
-
Ingår i: J Lipid Res. ; 43:10, s. 1743-9
-
Tidskriftsartikel (refereegranskat)abstract
- The supply of polyunsaturated fatty acids (PUFA) is important for optimal fetal and postnatal development. We have previously shown that leptin levels in suckling rats are reduced by maternal PUFA deficiency. In the present study, we evaluated the effect of maternal dietary intake of (n-3) and (n-6) PUFA on the leptin content in rat milk and serum leptin levels in suckling pups. For the last 10 days of gestation and throughout lactation, the rats were fed an isocaloric diet containing 7% linseed oil (n-3 diet), sunflower oil (n-6 diet), or soybean oil (n-6/n-3 diet). Body weight, body length, inguinal fat pad weight, and adipocyte size of the pups receiving the n-3 diet were significantly lower during the whole suckling period compared with n-6/n-3 fed pups. Body and fat pad weights of the n-6 fed pups were in between the other two groups at week one, but not different from the n-6/n-3 group at week 3. Feeding dams the n-3 diet resulted in decreased serum leptin levels in the suckling pups compared with pups in the n-6/n-3 group. The mean serum leptin levels of the n-6 pups were between the other two groups but not different from either group. There were no differences in the milk leptin content between the groups. These results show that the balance between the n-6 and n-3 PUFA in the maternal diet rather than amount of n-6 or n-3 PUFA per se could be important for adipose tissue growth and for maintaining adequate serum leptin levels in the offspring.
|
|
| 27. |
- Lönn, Lars, 1956, et al.
(författare)
-
Body weight and body composition changes after treatment of hyperthyroidism.
- 1998
-
Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 0021-972X. ; 83:12, s. 4269-73
-
Tidskriftsartikel (refereegranskat)abstract
- Body composition changes in nine adults with hyperthyroidism were determined with dual energy x-ray absorptiometry and computed tomography at diagnosis and after 3 and 12 months of euthyroidism achieved by surgery, antithyroid drugs, or treatment with radioiodine. Mean body weight was 67.6 kg at diagnosis and increased 2.7 kg (P=0.06) and 8.7 kg (P < 0.001) after 3 and 12 months of euthyroidism, respectively. Basal metabolic rate decreased from 2087 Cal/24 h at diagnosis to 1601 Cal/24 h at 12 months (P=0.001), whereas reported energy intake dropped from 3244 to 2436 Cal/24 h (P=0.01). According to dual energy x-ray absorptiometry, body fat was unchanged at 3 months, but increased by 5.3 kg (P < 0.0001) at 12 months. Fat-free mass increased 2.7 kg (P=0.003) at 3 months and 3.5 kg (P < 0.0001) at 12 months. Changes in bone mineral content and density did not reach significance. According to computed tomography, skeletal muscle plus skin areas increased by 11% (trunk) and 18% (thigh) at 3 months and by 17% (trunk) and 25% (thigh) at 12 months. There was no increase in sc adipose tissue (AT) at 3 months, but at 12 months this AT depot increased by 15% (thigh) and 33% (trunk). Intraperitoneal AT showed a borderline significant increase by 28% (P=0.08) at 3 months and by 40% (P=0.015) at 12 months. Areas of visceral organs and bone tissue of femur did not change significantly during the study. It is concluded that during early recovery from hyperthyroidism, priority is given to the replenishment of skeletal muscles and ip AT, whereas sc AT is increased at a later stage.
|
|
| 28. |
- Lönn, Malin, 1959, et al.
(författare)
-
Adipocyte size predicts incidence of type 2 diabetes in women
- 2010
-
Ingår i: The FASEB Journal. - 1530-6860. ; 24:1, s. 326-331
-
Tidskriftsartikel (refereegranskat)abstract
- Enlarged subcutaneous abdominal adipocytes have been shown to predict incidence of type 2 diabetes (T2D) in the Pima population of Arizona (USA). We investigated the role of subcutaneous abdominal adipocyte size (AAS), as well as femoral adipocyte size (FAS), as predictors of T2D in a population-based Swedish cohort. In 1974-1975, a sample of 1302 middle-aged women underwent a health examination, including anthropometry and evaluation of parental medical history. In addition, body composition (total body potassium and total body water), AAS and FAS (adipose tissue needle biopsy) were assessed in a subsample of 245 women. Incidence of T2D was followed until 2001, with 36 cases eligible for inclusion in this analysis. Women developing T2D had larger AAS at baseline vs. women remaining healthy (age/heredity-adjusted hazard ratio for increase of AAS by 1 sd [AAS-HR] 1.91; P<0.001). Further adjustment for both body fat percentage and waist-to-height ratio (WHtR) indicated a robust association. For FAS, the corresponding associations were consistently weaker. WHtR retained a strong predictive association independent of AAS and FAS (WHtR-HR 2.6 and 2.7, respectively; P<0.001). To conclude, in addition to the amount and distribution of body fat in women, subcutaneous adipocyte size, particularly in the abdominal region, predicts incidence of T2D in later life.
|
|
| 29. |
- Maliqueo, Manuel, et al.
(författare)
-
Continuous Administration of a P450 Aromatase Inhibitor Induces Polycystic Ovary Syndrome with a Metabolic and Endocrine Phenotype in Female Rats at Adult Age
- 2013
-
Ingår i: Endocrinology. - : The Endocrine Society. - 0013-7227 .- 1945-7170. ; 154:1, s. 434-445
-
Tidskriftsartikel (refereegranskat)abstract
- Studying the mechanisms for the complex pathogenesis of polycystic ovary syndrome (PCOS) requires animal models with endocrine, reproductive, and metabolic features of the syndrome. Hyperandrogenism seems to be a central factor in PCOS, leading to anovulation and insulin resistance. In female rats, continuous administration of letrozole, a nonsteroidal inhibitor of P450 aromatase, at 400 mu g/d starting before puberty induces hyperandrogenemia and reproductive abnormalities similar to those in women with PCOS. However, despite high circulating testosterone levels, these rats do not develop metabolic abnormalities, perhaps because of their supraphysiological testosterone concentrations or because estrogen synthesis is completely blocked in insulin-sensitive tissues. To test the hypothesis that continuous administration of lower doses of letrozole starting before puberty would result in both metabolic and reproductive phenotypes of PCOS, we performed a 12-wk dose-response study. At 21 d of age, 46 female Wistar rats were divided into two letrozole groups (100 or 200 mu g/d) and a control group (placebo). Both letrozole doses resulted in increased body weight, inguinal fat accumulation, anovulation, larger ovaries with follicular atresia and multiples cysts, endogenous hyperandrogemia, and lower estrogen levels. Moreover, rats that received 200 mu g/d had insulin resistance and enlarged adipocytes in inguinal and mesenteric fat depots, increased circulating levels of LH, decreased levels of FSH, and increased ovarian expression of Cyp17a1 mRNA. Thus, continuous administration of letrozole, 200 mu g/d, to female rats for 90 d starting before puberty results in a PCOS model with reproductive and metabolic features of the syndrome. (Endocrinology 154: 434-445, 2013)
|
|
| 30. |
- Mannerås Holm, Louise, 1980, et al.
(författare)
-
Coagulation and Fibrinolytic Disturbances in Women with Polycystic Ovary Syndrome.
- 2011
-
Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 96:4, s. 1068-76
-
Tidskriftsartikel (refereegranskat)abstract
- Context: Studies of fibrinolysis/coagulation status in women with polycystic ovary syndrome (PCOS) are contradictory. Objectives: The aim of the study was to investigate whether women with PCOS have disturbed circulating levels of fibrinolysis/coagulation markers and, if so, whether the disturbances are related to hemodynamics, metabolic variables, sex steroids, SHBG, lipids, and inflammatory variables in women with PCOS. Design/Main Outcome Measures: Anthropometric variables, hemodynamics, circulating hemostatic and inflammatory markers, and serum lipid profile were measured in women with untreated PCOS (n = 74) and controls (n = 31). Results: After adjustments for age and body mass index (BMI), circulating plasminogen activator inhibitor 1 (PAI-1) activity and fibrinogen levels were higher in women with PCOS than controls; lipid profile, blood pressure, and levels of D-dimer, von Willebrand factor, factor VIII, tissue plasminogen activator, and inflammatory markers were comparable in the two groups. In multiple linear regression analyses including women with PCOS, low SHBG and high insulin predicted high PAI-1 activity (R(2) = 0.526; P < 0.001); elevated high-sensitivity C-reactive protein and soluble E-selectin in combination with heart rate predicted high fibrinogen (R(2) = 0.333; P < 0.001). Differences in PAI-1 activity were not significant after adjustments for age, BMI, SHBG, and insulin. Conclusions: PCOS is characterized by a prothrombotic state, as reflected by increased PAI-1 activity and fibrinogen, without signs of dyslipidemia or a proinflammatory state. Low SHBG and high insulin may partly explain the BMI-independent difference in PAI-1 activity between women with PCOS and controls. High-sensitivity C-reactive protein and E-selectin may be involved in regulating fibrinogen in PCOS.
|
|
| 31. |
- Mannerås, Louise, 1980, et al.
(författare)
-
Acupuncture and exercise restore adipose tissue expression of sympathetic markers and improve ovarian morphology in rats with dihydrotestosterone-induced PCOS.
- 2009
-
Ingår i: American journal of physiology. Regulatory, integrative and comparative physiology. - : American Physiological Society. - 0363-6119 .- 1522-1490. ; 296:4
-
Tidskriftsartikel (refereegranskat)abstract
- Altered activity of the sympathetic nervous system, which innervates adipose and ovarian tissue, may play a role in polycystic ovary syndrome (PCOS). We hypothesize that electro-acupuncture (EA) and physical exercise reduce sympathetic activity by stimulating ergoreceptors and somatic afferent pathways in muscles. Here we investigated the effects of low-frequency EA and physical exercise on mRNA expression of sympathetic markers in adipose tissue and on ovarian morphology in female rats that received dihydrotestosterone (DHT) continuously, starting before puberty, to induce PCOS. At age 11 wk, rats with DHT-induced PCOS were randomly divided into three groups: PCOS, PCOS plus EA, and PCOS plus exercise. The latter two groups received 2-Hz EA (evoking muscle twitches) three times/week or had free access to a running wheel for 4-5 wk. In mesenteric adipose tissue, expression of beta(3)-adrenergic receptor (ADRB3), nerve growth factor (NGF), and neuropeptide Y (NPY) mRNA was higher in untreated PCOS rats than in controls. Low-frequency EA and exercise downregulated mRNA expression of NGF and NPY, and EA also downregulated expression of ADRB3, compared with untreated rats with DHT-induced PCOS. EA and exercise improved ovarian morphology, as reflected in a higher proportion of healthy antral follicles and a thinner theca interna cell layer than in untreated PCOS rats. These findings support the theory that increased sympathetic activity contributes to the development and maintenance of PCOS and that the effects of EA and exercise may be mediated by modulation of sympathetic outflow to the adipose tissue and ovaries.
|
|
| 32. |
- Mannerås, Louise, 1980, et al.
(författare)
-
Beneficial metabolic effects of the Malaysian herb Labisia pumila var. alata in a rat model of polycystic ovary syndrome.
- 2010
-
Ingår i: Journal of ethnopharmacology. - : Elsevier BV. - 1872-7573 .- 0378-8741. ; 127, s. 346-351
-
Tidskriftsartikel (refereegranskat)abstract
- AIM OF THE STUDY: New options are needed to prevent and treat metabolic disorders associated with polycystic ovary syndrome (PCOS). Labisia pumila var. alata (LPva)-a Malaysian herb thought to have phytoestrogenic effects-has shown promise in reducing body weight gain in ovariectomized rats. In this study, we investigated the effect of LPva on body composition and metabolic features in female rats treated continuously with dihydrotestosterone, starting before puberty, to induce PCOS. MATERIAL AND METHODS: At 9 weeks of age, the PCOS rats were randomly subdivided into two groups; PCOS LPva and PCOS control. PCOS LPva rats received a daily oral dose of LPva (50mg/kg body weight), dissolved in 1ml of deionised water, for 4-5 weeks. PCOS controls received 1ml of deionised water on the same schedule. RESULTS: LPva increased uterine weight (27%) and insulin sensitivity (36%) measured by euglycemic hyperinsulinemic clamp. Plasma resistin levels were increased and lipid profile was improved in LPva rats. In adipose tissue, LPva decreased leptin mRNA expression but did not affect expression of resistin and adiponectin. No effects on body composition, adipocyte size, or plasma leptin levels were observed. CONCLUSION: LPva increases uterine weight, indicating estrogenic effects, and improves insulin sensitivity and lipid profile in PCOS rats without affecting body composition.
|
|
| 33. |
|
|
| 34. |
- Olofsson, Roger, 1978, et al.
(författare)
-
Isolated hepatic perfusion as a treatment for uveal melanoma liver metastases (the SCANDIUM trial) : study protocol for a randomized controlled trial
- 2014
-
Ingår i: Trials. - : Springer Science and Business Media LLC. - 1745-6215. ; 15, s. 317-
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Uveal melanoma is the most common primary intraocular malignancy in adults. Despite successful control of the primary tumor, metastatic disease will ultimately develop in approximately 50% of patients, with the liver being the most common site for metastases. The median survival for patients with liver metastases is between 6 and 12 months, and no treatment has in randomized trials ever been shown to prolong survival. A previous phase II trial using isolated hepatic perfusion (IHP) has suggested a 14-month increase in overall survival compared with a historic control group consisting of the longest surviving patients in Sweden during the same time period (26 versus 12 months). Methods/Design: This is the protocol for a multicenter phase III trial randomizing patients with isolated liver metastases of uveal melanoma to IHP or best alternative care (BAC). Inclusion criteria include liver metastases (verified by biopsy) and no evidence of extra-hepatic tumor manifestations by positron emission tomography-computed tomography (PET-CT). The primary endpoint is overall survival at 24 months, with secondary endpoints including response rate, progression-free survival, and quality of life. The planned sample size is 78 patients throughout five years. Discussion: Patients with isolated liver metastases of uveal melanoma origin have a short expected survival and no standard treatment option exists. This is the first randomized clinical trial to evaluate IHP as a treatment option with overall survival being the primary endpoint.
|
|
| 35. |
- Palming, Jenny, 1975, et al.
(författare)
-
Plasma cells and Fc receptors in human adipose tissue--lipogenic and anti-inflammatory effects of immunoglobulins on adipocytes
- 2006
-
Ingår i: Biochem Biophys Res Commun. - : Elsevier BV. - 0006-291X .- 1090-2104. ; 343:1, s. 43-8
-
Tidskriftsartikel (refereegranskat)abstract
- We have previously reported high immunoglobulin expression in human omental adipose tissue. The aim of this work was to investigate plasma cell density and Fc receptor (FcR) expression in human adipose tissue depots and in vitro effects of immunoglobulins on adipocyte function. Plasma cell density was higher in the visceral compared to the subcutaneous depot (10.0+/-1.56% and 5.2+/-0.98%, respectively, n=20, p<0.05). Microarray analysis revealed expression of four FcR genes in adipose tissue; FCGR2A, FCGR2B, FCER1G, and FCGRT. FCGR2A was highly expressed in adipocytes in both depots and this was verified by immunohistochemistry. Expression of IL-1beta and IL-6 was markedly reduced in adipocytes after incubation with the Fc moiety of immunoglobulin G (Fc) (p<0.01). Furthermore, Fc stimulated adipocyte lipogenesis as potently as insulin (p<0.05), but did not influence lipolysis. In conclusion, immunoglobulins produced by plasma cells in human adipose tissue could influence adipocyte metabolism and cytokine production.
|
|
| 36. |
- Stener-Victorin, Elisabet, 1964, et al.
(författare)
-
Effects of acupuncture and exercise on insulin sensitivity, adipose tissue characteristics, and markers of coagulation and fibrinolysis in women with polycystic ovary syndrome: secondary analyses of a randomized controlled trial.
- 2012
-
Ingår i: Fertility and Sterility. - : Elsevier BV. - 0015-0282 .- 1556-5653. ; 97:2, s. 501-508
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: To investigate the possible effects of low-frequency electro-acupuncture (EA) and physical exercise on markers of coagulation and fibrinolysis, insulin sensitivity, and adipose tissue characteristics in women with PCOS. Design: Secondary analyses of a prospective, randomized controlled clinical trial. ClinicalTrials.gov (identifier NCT00484705) Settings: Department of Physiology and Department of Obstetrics and Gynecology, Universtiy of Gothenburg. Patients/Interventions: Eighty-four women with PCOS were randomized to sixteen weeks of low-frequency EA (14 treatments), physical exercise (at least 3 times/week) or no intervention. Main outcome measures: Anthropometrics, circulating coagulation and fibrinolytic markers, insulin sensitivity (euglycemic hyperinsulinemic clamp), hemodynamics, and adipose tissue morphology/function recorded at baseline, after 16 weeks of intervention, and after a 16 week follow-up. Results: In the low-frequency EA group, circulating plasminogen activator inhibitor (PAI-1) activity decreased by 21.8% after 16 weeks of intervention and by 31.1% at the 16 week follow-up and differed from the physical exercise and the no-intervention groups. The EA group had decreases in circulating fibrinogen and t-PA, sagittal diameter, and diastolic blood pressure after treatment, and fibrinogen remained lower at the 16-week follow-up. In the physical exercise group, lipoprotein lipase activity increased and diastolic blood pressure decreased after treatment, and both diastolic and systolic blood pressure were lower at follow-up. No other variables were affected. Conclusions: Low-frequency EA counteracted a possible prothrombotic state in women with PCOS, as reflected by a decrease in PAI-1 activity. Despite within-group improvements, there were no between-group differences in anthropometric, metabolic, or hemodynamic variables after 16 weeks of EA or physical exercise at the dose/intensity studied.
|
|
| 37. |
- Svensson, Henrik, 1982, et al.
(författare)
-
Adiponectin, chemerin, cytokines, and dipeptidyl peptidase 4 are released from human adipose tissue in a depot-dependent manner: an in vitro system including human serum albumin
- 2014
-
Ingår i: BMC Endocrine Disorders. - : Springer Science and Business Media LLC. - 1472-6823. ; 1:7
-
Tidskriftsartikel (refereegranskat)abstract
- Abstract Background Adipose tissue (AT) contributes to metabolic dysfunction through imbalanced production of adipokines, including cytokines. Visceral AT in particular is associated with metabolic disorders, indicating a specific secretory status. The relative significance of different human AT depots in adipokine release is not fully known. Further, previous in vitro systems usually included medium containing bovine serum albumin (BSA), which may induce cytokine release. Our aim was to compare release of a number of adipokines/cytokines – all implicated in insulin resistance – from human subcutaneous and visceral AT in a short-term incubation system minimizing cytokine induction and including repeated measurements during 24 h. A prerequisite was to evaluate a potential alternative to BSA in the incubation medium. Methods Subcutaneous and/or visceral AT from 17 patients (age 20–68 years; BMI 22.6–56.7 kg/m2) undergoing elective surgery was incubated for 2, 4, 6, 8, and 24 h in medium with or without 1% BSA or human serum albumin (HSA). Medium concentrations of adiponectin, chemerin, nine cytokines, dipeptidyl peptidase 4 (DPP4), and omentin were analyzed by multiplex immunoassay or ELISA. Adipocyte size, AT macrophage density, and medium concentrations of endotoxin were determined. Results Cytokine release was induced by BSA but not by HSA. In evaluation of the final incubation protocol including 1% HSA, and as expected, adiponectin release was higher from subcutaneous biopsies of nonobese than of obese subjects and inversely associated with adipocyte size; omentin was released almost exclusively from visceral AT. Exploratory incubations revealed more abundant release of chemerin, cytokines (except IL-6), and DPP4 from the visceral depot, while adiponectin release was higher from subcutaneous than visceral AT. Release was linear for a maximum of 2–6 h. Macrophage density was higher in visceral than subcutaneous AT. Levels of endotoxin in the medium were negligible. Conclusions Adiponectin, chemerin, many cytokines, and DPP4 are released from human AT in a depot-dependent manner. These results highlight functional differences between visceral and subcutaneous AT, and a mechanistic link between regional fat accumulation and metabolic disorders. Supplementation of human AT incubation medium with HSA rather than BSA is recommended to minimize induction of cytokine release.
|
|
| 38. |
- Svensson, Henrik, et al.
(författare)
-
Inflammatory and metabolic markers in relation to outcome of in vitro fertilization in a cohort of predominantly overweight and obese women.
- 2022
-
Ingår i: Scientific reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 12:1
-
Tidskriftsartikel (refereegranskat)abstract
- For overweight and obese women undergoing in vitro fertilization (IVF) the pregnancy and live birth rates are compromised while the underlying mechanisms and predictors are unclear. The aim was to explore the association between adipose tissue-related inflammatory and metabolic markers and the pregnancy and live birth outcome of IVF in a cohort of predominantly overweight and obese women. Serum samples, fulfilling standardizing criteria, were identified from 195 women having participated in either the control (n=131) or intervention (n=64) group of a randomized controlled trial (RCT), seeking to evaluate the effect of a weight reduction intervention on IVF outcome in obese women. Serum high-sensitivity C-reactive protein (hsCRP) and the adipokines leptin and adipocyte fatty acid-binding protein (AFABP) were analyzed for the whole cohort (n=195) in samples collected shortly before IVF [at randomization (control group), after intervention (intervention group)]. Information on age, anthropometry [BMI, waist circumference, waist-to-height ratio (WHtR)], pregnancy and live birth rates after IVF, as well as the spontaneous pregnancy rate, was extracted or calculated from collected data. The women of the original intervention group were also characterized at randomization regarding all variables. Eight women [n=3 original control group (2.3%), n=5 original intervention group (7.8%)] conceived spontaneously before starting IVF. BMI category proportions in the cohort undergoing IVF (n=187) were 1.6/20.1/78.3% (normal weight/overweight/obese). The pregnancy and live birth rates after IVF for the cohort were 35.8% (n=67) and 24.6% (n=46), respectively. Multivariable logistic regression revealed that none of the variables (age, hsCRP, leptin, AFABP, BMI, waist circumference, WHtR) were predictive factors of pregnancy or live birth after IVF. Women of the original intervention group displayed reductions in hsCRP, leptin, and anthropometric variables after intervention while AFABP was unchanged. In this cohort of predominantly overweight and obese women undergoing IVF, neither low-grade inflammation, in terms of hsCRP, other circulating inflammatory and metabolic markers released from adipose tissue (leptin, AFABP), nor anthropometric measures of adiposity or adipose tissue distribution (BMI, waist, WHtR) were identified as predictive factors of pregnancy or live birth rate.Trial registration: ClinicalTrials.gov number, NCT01566929. Trial registration date 30-03-2012, retrospectively registered.
|
|
