| 1. |
- Lager, Susanne, 1978, et al.
(författare)
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Perinatal lack of maternal IL-6 promotes increased adiposity during adulthood in mice.
- 2011
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Ingår i: Endocrinology. - : The Endocrine Society. - 1945-7170 .- 0013-7227. ; 152:4, s. 1336-46
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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.
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| 2. |
- Thorgeirsdottir, Lilja, et al.
(författare)
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Study protocol: establishment of a multicentre pre-eclampsia database and biobank in Sweden: GO PROVE and UP MOST, a prospective cohort study
- 2021
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Ingår i: BMJ Open. - : BMJ Publishing Group Ltd. - 2044-6055. ; 11:11
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Introduction Pre-eclampsia, a multisystem disorder in pregnancy, is one of the most common causes of maternal morbidity and mortality worldwide. However, we lack methods for objective assessment of organ function in pre-eclampsia and predictors of organ impairment during and after pre-eclampsia. The women’s and their partners’ experiences of pre-eclampsia have not been studied in detail. To phenotype different subtypes of the disorder is of importance for prediction, prevention, surveillance, treatment and follow-up of pre-eclampsia.The aim of this study is to set up a multicentre database and biobank for pre-eclampsia in order to contribute to a safer and more individualised treatment and care.Methods and analysis This is a multicentre cohort study. Prospectively recruited pregnant women ≥18 years, diagnosed with pre-eclampsia presenting at Sahlgrenska University Hospital, Uppsala University Hospital and at Södra Älvsborgs Hospital, Sweden, as well as normotensive controls are eligible for participation. At inclusion and at 1-year follow-up, the participants donate biosamples that are stored in a biobank and they are also asked to participate in various organ-specific evaluations. In addition, questionnaires and interviews regarding the women’s and partner’s experiences are distributed at follow-up.Ethics and dissemination By creating a database and biobank, we will provide the means to explore the disorder in a broader sense and allow clinical and laboratory discoveries that can be translated to clinical trials aiming at improved care of women with pre-eclampsia. Further, to evaluate experiences and the psychological impact of being affected by pre-eclampsia can improve the care of pregnant women and their partners. In case of incidental pathological findings during examinations performed, they will be handled in accordance with clinical routine. Data are stored in a secure online database. Biobank samples are identified through the women’s personal identification number and pseudonymised after identification in the biobank before analysis.This study was approved by the regional ethical review board in Gothenburg on 28 December 2018 (approval number 955-18) and by the Swedish Ethical Review Authority on 27 February 2019 (approval number 2019-00309).
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| 3. |
- Jansson, Nina, 1976, et al.
(författare)
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Activation of Placental mTOR Signaling and Amino Acid Transporters in Obese Women Giving Birth to Large Babies.
- 2013
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 98:1, s. 105-13
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Tidskriftsartikel (refereegranskat)abstract
- Context: Babies of obese women are often large at birth, which is associated with perinatal complications and metabolic syndrome later in life. The mechanisms linking maternal obesity to fetal overgrowth are largely unknown. Objective: We tested the hypothesis that placental insulin/IGF-I and mammalian target of rapamycin (mTOR) signaling is activated and amino acid transporter activity is increased in large babies of obese women. Design and Setting: Pregnant women were recruited prospectively for collection of placental tissue at a university hospital and academic biomedical center. Patients or Other Participants: Twenty-three Swedish pregnant women with first trimester body mass index ranging from 18.5 to 44.9 kg/m(2) and with uncomplicated pregnancies participated in the study. Interventions: There were no interventions. Main Outcome Measures: We determined the phosphorylation of key signaling molecules (including Akt, IRS-1, S6K1, 4EBP-1, RPS6, and AMPK) in the placental insulin/IGF-I, AMPK, and mTOR signaling pathways. The activity and protein expression of the amino acid transporter systems A and L were measured in syncytiotrophoblast microvillous plasma membranes. Results: Birth weights (range, 3025-4235 g) were positively correlated to maternal body mass index (P < 0.05). The activity of placental insulin/IGF-I and mTOR signaling was positively correlated (P < 0.001), whereas AMPK phosphorylation was inversely (P < 0.05) correlated to birth weight. Microvillous plasma membrane system A, but not system L, activity and protein expression of the system A isoform SNAT2 were positively correlated to birth weight (P < 0.001). Conclusions: Up-regulation of specific placental amino acid transporter isoforms may contribute to fetal overgrowth in maternal obesity. This effect may be mediated by activation of insulin/IGF-I and mTOR signaling pathways, which are positive regulators of placental amino acid transporters.
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| 4. |
- Lager, Susanne, 1978
(författare)
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Cytokines and lipids in pregnancy – effects on developmental programming and placental nutrient transfer
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Metabolic disturbances, in particular those associated with nutritional challenges, that take place during development, both in utero and early postnatal life, have long-lasting health consequences on an individual. The most pronounced evidence of these challenges is a deviation in birth weight. This is a process recognized as developmental programming of adult health and disease. The etiologies of metabolic health disorders such as insulin resistance and obesity are complex; and developmental programming may be a factor contributing to the increased worldwide prevalence. Women who are overweight or diabetic have a higher risk for delivering large infants, and such infants are themselves at an increased risk of developing metabolic disturbances. Fetal growth is intimately linked to placental nutrient transport capacity. We hypothesized that the altered nutritional, hormonal, and metabolic environment of overweight or diabetic women (hyperlipidemia, pro-inflammatory status) modifies placental nutrient transport and contributes to altering the adult phenotype of these children. The aim of this thesis was to investigate the importance of maternal interleukin-6 during development for offspring adiposity and insulin sensitivity at an adult age in mice, examine the effects of cytokines and lipids on human placental nutrient transport functions and to describe mechanisms underlying these changes. The main findings of this thesis were: Interleukin-6 deficient mice weighed more and had a more pronounced adiposity which developed at a younger age if born of interleukin-6 deficient dams compared to dams with a heterozygote interleukin-6 genotype. At an older age (6 to 7 months of age) both groups had enlarged adipocytes and reduced insulin sensitivity. Wild-type mice fostered by interleukin-6 deficient dams also weighed more, had an augmented adiposity and larger adipocytes, and higher systemic leptin levels at an adult age compared to wild-type mice fostered by wild-type dams. Milk from interleukin-6 deficient dams contained twofold higher leptin concentrations compared to milk from wild-type dams. These observations suggest that lack of maternal interleukin-6 or, alternatively, factors modified by this cytokine have developmental programming effects that contribute to the development of adipose tissue and obesity. Using primary cell cultures of human trophoblast cells, we demonstrated the production site of placental lipoprotein lipase to be cytotrophoblast cells and syncytiotrophoblast. We also observed that elevated levels of free fatty acids and triglycerides reduce trophoblast lipoprotein lipase activity; while insulin, interleukin-6, and tumor necrosis factor-α had no regulatory effect on lipoprotein lipase. Interleukin-6 did however increase placental lipid accumulation. Free fatty acids changed the release of cytokines from trophoblast cells and stimulated amino acid uptake through the System A transporter. Using RNA interference techniques, we demonstrated that toll-like receptor 4 is required for fatty acids to stimulate placental amino acid uptake. In summary, we found that an altered maternal hormonal or metabolic environment can affect the developing fetus, causing long-term programming effects on adult phenotype. The effects of cytokines on placental lipid transport were moderate; however, there was a pronounced effect of fatty acids upon amino acid uptake. Therefore maternal circulating factors known to be altered in obesity may augment placental nutrient transport and contribute to an accelerated fetal growth.
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| 5. |
- Lager, Susanne, 1978, et al.
(författare)
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Effect of IL-6 and TNF-α on fatty acid uptake in cultured human primary trophoblast cells.
- 2011
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Ingår i: Placenta. - : Elsevier BV. - 1532-3102 .- 0143-4004. ; 32:2, s. 121-7
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Tidskriftsartikel (refereegranskat)abstract
- Maternal obesity and gestational diabetes (GDM) are conditions associated with fetal overgrowth and excessive fat accumulation in the fetus, implicating an increased placental nutrient transfer in these pregnancies. Obese and GDM mothers have altered metabolism and hormone levels, including elevation of maternal circulatory lipids and pro-inflammatory cytokines. We tested the hypothesis that interleukin (IL)-6 and tumor necrosis factor (TNF)-α stimulate placental fatty acid transport, as these pro-inflammatory cytokines have been shown to affect lipid metabolism in other tissues. In cultured primary human trophoblast cells IL-6, but not TNF-α, stimulated fatty acid accumulation, as measured by BODIPY fluorescence. The increased fatty acid accumulation could not be explained by an increased expression of key components in placental fatty acid transport, such as adipophilin, fatty acid transport protein (FATP)1, FATP4, or lipoprotein lipase. In a cohort of lean and overweight/obese pregnant women, increasing maternal third trimester IL-6 plasma concentrations correlated with decreasing placental lipoprotein lipase activity. However, as no effect on lipoprotein lipase activity was observed in cultured trophoblast cells after exposure to either IL-6 or TNF-α, the correlation between maternal circulatory IL-6 levels and placental lipoprotein lipase activity at term is unlikely to represent a cause-and-effect relationship. In conclusion, high levels of IL-6 stimulate trophoblast fatty acid accumulation, which could contribute to an excessive nutrient transfer in conditions associated with elevated maternal IL-6 such as obesity and gestational diabetes.
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| 6. |
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| 7. |
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| 8. |
- Lager, Susanne, 1978, et al.
(författare)
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Oleic acid stimulates system A amino acid transport in primary human trophoblast cells mediated by toll-like receptor 4
- 2013
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Ingår i: Journal of Lipid Research. - 0022-2275. ; 54:3, s. 725-733
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Tidskriftsartikel (refereegranskat)abstract
- Obese women have an increased risk to deliver large babies. However, the mechanisms underlying fetal overgrowth in these pregnancies are not well understood. Obese pregnant women typically have elevated circulating lipid levels. We tested the hypothesis that fatty acids stimulate placental amino acid transport, mediated via toll-like receptor 4 (TLR4) and mammalian target of rapamycin (mTOR) signaling pathways. Circulating NEFA levels and placental TLR4 expression were assessed in women with varying prepregnancy body mass index (BMI). The effects of oleic acid on system A and system L amino acid transport, and on the activation of the mTOR (4EBP1, S6K1, rpS6), TLR4 (IĸBɑ, JNK, p38 MAPK), and STAT3 signaling pathways were determined in cultured primary human trophoblast cells. Maternal circulating NEFAs (n = 33), but not placental TLR4 mRNA expression (n = 16), correlated positively with BMI (P < 0.05). Oleic acid increased trophoblast JNK and STAT3 phosphorylation (P < 0.05), whereas mTOR activity was unaffected. Furthermore, oleic acid doubled trophoblast system A activity (P < 0.05), without affecting system L activity. siRNA-mediated silencing of TLR4 expression prevented the stimulatory effect of oleic acid on system A activity. Our data suggest that maternal fatty acids can increase placental nutrient transport via TLR4, thereby potentially affecting fetal growth.
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